draft-ietf-mmusic-sdp-mux-attributes-19.txt   rfc8859.txt 
Network Working Group S. Nandakumar Internet Engineering Task Force (IETF) S. Nandakumar
Internet-Draft Cisco Request for Comments: 8859 Cisco
Intended status: Standards Track August 27, 2020 Category: Standards Track January 2021
Expires: February 28, 2021 ISSN: 2070-1721
A Framework for SDP Attributes when Multiplexing A Framework for Session Description Protocol (SDP) Attributes When
draft-ietf-mmusic-sdp-mux-attributes-19 Multiplexing
Abstract Abstract
The purpose of this specification is to provide a framework for The purpose of this specification is to provide a framework for
analyzing the multiplexing characteristics of Session Description analyzing the multiplexing characteristics of Session Description
Protocol (SDP) attributes when SDP is used to negotiate the usage of Protocol (SDP) attributes when SDP is used to negotiate the usage of
single 5-tuple for sending and receiving media associated with a single 5-tuple for sending and receiving media associated with
multiple media descriptions. multiple media descriptions.
This specification also categorizes the existing SDP attributes based This specification also categorizes the existing SDP attributes based
on the framework described herein. on the framework described herein.
Status of This Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Terminology
3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 6 3. Motivation
4. SDP Attribute Analysis Framework . . . . . . . . . . . . . . 6 4. SDP Attribute Analysis Framework
4.1. Category: NORMAL . . . . . . . . . . . . . . . . . . . . 7 4.1. Category: NORMAL
4.2. Category: CAUTION . . . . . . . . . . . . . . . . . . . . 7 4.2. Category: CAUTION
4.3. Category: IDENTICAL . . . . . . . . . . . . . . . . . . . 8 4.3. Category: IDENTICAL
4.4. Category: SUM . . . . . . . . . . . . . . . . . . . . . . 9 4.4. Category: SUM
4.5. Category: TRANSPORT . . . . . . . . . . . . . . . . . . . 9 4.5. Category: TRANSPORT
4.6. Category: INHERIT . . . . . . . . . . . . . . . . . . . . 10 4.6. Category: INHERIT
4.7. Category: IDENTICAL-PER-PT . . . . . . . . . . . . . . . 11 4.7. Category: IDENTICAL-PER-PT
4.8. Category: SPECIAL . . . . . . . . . . . . . . . . . . . . 12 4.8. Category: SPECIAL
4.9. Category: TBD . . . . . . . . . . . . . . . . . . . . . . 12 4.9. Category: TBD
5. Analysis of Existing Attributes . . . . . . . . . . . . . . . 12 5. Analysis of Existing Attributes
5.1. RFC4566: SDP . . . . . . . . . . . . . . . . . . . . . . 13 5.1. RFC 4566: SDP
5.2. RFC4585: RTP/AVPF . . . . . . . . . . . . . . . . . . . . 14 5.2. RFC 4585: RTP/AVPF
5.3. RFC5761: Multiplexing RTP and RTCP . . . . . . . . . . . 15 5.3. RFC 5761: Multiplexing RTP and RTCP
5.4. RFC3312: Integration of Resource Management and SIP . . . 15 5.4. RFC 3312: Integration of Resource Management and SIP
5.5. RFC4574: SDP Label Attribute . . . . . . . . . . . . . . 16 5.5. RFC 4574: SDP "label" Attribute
5.6. RFC5432: QOS Mechanism Selection in SDP . . . . . . . . . 16 5.6. RFC 5432: QoS Mechanism Selection in SDP
5.7. RFC4568: SDP Security Descriptions . . . . . . . . . . . 17 5.7. RFC 4568: SDP Security Descriptions
5.8. RFC5762: RTP over DCCP . . . . . . . . . . . . . . . . . 17 5.8. RFC 5762: RTP over DCCP
5.9. RFC6773: DCCP-UDP Encapsulation . . . . . . . . . . . . . 18 5.9. RFC 6773: DCCP-UDP Encapsulation
5.10. RFC5506: Reduced-Size RTCP in RTP Profile . . . . . . . . 19 5.10. RFC 5506: Reduced-Size RTCP in RTP Profile
5.11. RFC6787: Media Resource Control Protocol Version 2 . . . 19 5.11. RFC 6787: Media Resource Control Protocol Version 2
5.12. RFC5245: ICE . . . . . . . . . . . . . . . . . . . . . . 20 5.12. RFC 8445: ICE
5.13. RFC5285: RTP Header Extensions . . . . . . . . . . . . . 21 5.13. RFC 5285: RTP Header Extensions
5.14. RFC3605: RTCP attribute in SDP . . . . . . . . . . . . . 22 5.14. RFC 3605: RTCP Attribute in SDP
5.15. RFC5576: Source-Specific SDP Attributes . . . . . . . . . 22 5.15. RFC 5576: Source-Specific SDP Attributes
5.16. RFC7273: RTP Clock Source Signalling . . . . . . . . . . 23 5.16. RFC 7273: RTP Clock Source Signaling
5.17. RFC6236: Image Attributes in SDP . . . . . . . . . . . . 24 5.17. RFC 6236: Image Attributes in SDP
5.18. RFC7197: Duplication Delay Attribute in SDP . . . . . . . 25 5.18. RFC 7197: Duplication Delay Attribute in SDP
5.19. RFC7266: RTCP XR Blocks for MOS Metric Reporting . . . . 25 5.19. RFC 7266: RTCP XR Blocks for MOS Metric Reporting
5.20. RFC6285: Rapid Acquisition of Multicast RTP Sessions . . 25 5.20. RFC 6285: Rapid Acquisition of Multicast RTP Sessions
5.21. RFC6230: Media Control Channel Framework . . . . . . . . 26 5.21. RFC 6230: Media Control Channel Framework
5.22. RFC6364: SDP Elements for FEC Framework . . . . . . . . . 26 5.22. RFC 6364: SDP Elements for FEC Framework
5.23. RFC4796: Content Attribute . . . . . . . . . . . . . . . 27 5.23. RFC 4796: "content" Attribute
5.24. RFC3407: SDP Simple Capability Declaration . . . . . . . 27 5.24. RFC 3407: SDP Simple Capability Declaration
5.25. RFC6284: Port Mapping between Unicast and Multicast RTP 5.25. RFC 6284: Port Mapping between Unicast and Multicast RTP
Sessions . . . . . . . . . . . . . . . . . . . . . . . . 28 Sessions
5.26. RFC6714: MSRP-CEMA . . . . . . . . . . . . . . . . . . . 29 5.26. RFC 6714: MSRP-CEMA
5.27. RFC4583: SDP Format for BFCP Streams . . . . . . . . . . 29 5.27. RFC 4583: SDP Format for BFCP Streams
5.28. RFC5547: SDP Offer/Answer for File Transfer . . . . . . . 30 5.28. RFC 5547: SDP Offer/Answer for File Transfer
5.29. RFC6849: SDP and RTP Media Loopback Extension . . . . . . 30 5.29. RFC 6849: SDP and RTP Media Loopback Extension
5.30. RFC5760: RTCP with Unicast Feedback . . . . . . . . . . . 31 5.30. RFC 5760: RTCP with Unicast Feedback
5.31. RFC3611: RTCP XR . . . . . . . . . . . . . . . . . . . . 31 5.31. RFC 3611: RTCP XR
5.32. RFC5939: SDP Capability Negotiation . . . . . . . . . . . 32 5.32. RFC 5939: SDP Capability Negotiation
5.33. RFC6871: SDP Media Capabilities Negotiation . . . . . . . 32 5.33. RFC 6871: SDP Media Capabilities Negotiation
5.34. RFC7006: Miscellaneous Capabilities Negotiation SDP . . . 33 5.34. RFC 7006: Miscellaneous Capabilities Negotiation in SDP
5.35. RFC4567: Key Management Extensions for SDP and RTSP . . . 34 5.35. RFC 4567: Key Management Extensions for SDP and RTSP
5.36. RFC4572: Comedia over TLS in SDP . . . . . . . . . . . . 35 5.36. RFC 4572: Comedia over TLS in SDP
5.37. RFC4570: SDP Source Filters . . . . . . . . . . . . . . . 35 5.37. RFC 4570: SDP Source Filters
5.38. RFC6128: RTCP Port for Multicast Sessions . . . . . . . . 36 5.38. RFC 6128: RTCP Port for Multicast Sessions
5.39. RFC6189: ZRTP . . . . . . . . . . . . . . . . . . . . . . 36 5.39. RFC 6189: ZRTP
5.40. RFC4145: Connection-Oriented Media . . . . . . . . . . . 37 5.40. RFC 4145: Connection-Oriented Media
5.41. RFC6947: The SDP altc Attribute . . . . . . . . . . . . . 37 5.41. RFC 6947: The SDP "altc" Attribute
5.42. RFC7195: SDP Extension for Circuit Switched Bearers 5.42. RFC 7195: SDP Extension for Circuit-Switched Bearers in
in PSTN . . . . . . . . . . . . . . . . . . . . . . . . . 38 PSTN
5.43. RFC7272: IDMS Using the RTP Control Protocol (RTCP) . . . 38 5.43. RFC 7272: IDMS Using the RTP Control Protocol (RTCP)
5.44. RFC5159: Open Mobile Alliance (OMA) Broadcast (BCAST) SDP 5.44. RFC 5159: Open Mobile Alliance (OMA) Broadcast (BCAST) SDP
Attributes . . . . . . . . . . . . . . . . . . . . . . . 39 Attributes
5.45. RFC6193: Media Description for IKE in SDP . . . . . . . . 39 5.45. RFC 6193: Media Description for IKE in SDP
5.46. RFC2326: Real Time Streaming Protocol . . . . . . . . . . 40 5.46. RFC 2326: Real Time Streaming Protocol
5.47. RFC6064: SDP and RTSP Extensions for 3GPP . . . . . . . . 41 5.47. RFC 7826: Real-Time Streaming Protocol
5.48. RFC3108: ATM SDP . . . . . . . . . . . . . . . . . . . . 43 5.48. RFC 6064: SDP and RTSP Extensions for 3GPP
5.49. 3GPP TS 26.114 . . . . . . . . . . . . . . . . . . . . . 45 5.49. RFC 3108: ATM SDP
5.50. 3GPP TS 183.063 . . . . . . . . . . . . . . . . . . . . . 46 5.50. 3GPP TS 183.063
5.51. 3GPP TS 24.229 . . . . . . . . . . . . . . . . . . . . . 46 5.51. 3GPP TS 24.229
5.52. ITU T.38 . . . . . . . . . . . . . . . . . . . . . . . . 47 5.52. ITU T.38
5.53. ITU-T Q.1970 . . . . . . . . . . . . . . . . . . . . . . 49 5.53. ITU-T Q.1970
5.54. ITU-T H.248.15 . . . . . . . . . . . . . . . . . . . . . 49 5.54. ITU-T H.248.15
5.55. RFC4975: The Message Session Relay Protocol . . . . . . . 50 5.55. RFC 4975: The Message Session Relay Protocol
5.56. Historical Attributes . . . . . . . . . . . . . . . . . . 51 5.56. Historical Attributes
6. bwtype Attribute Analysis . . . . . . . . . . . . . . . . . . 51 6. bwtype Attribute Analysis
6.1. RFC4566: SDP . . . . . . . . . . . . . . . . . . . . . . 52 6.1. RFC 4566: SDP
6.2. RFC3556: SDP Bandwidth Modifiers for RTCP Bandwidth . . . 52 6.2. RFC 3556: SDP Bandwidth Modifiers for RTCP Bandwidth
6.3. RFC3890: Bandwidth Modifier for SDP . . . . . . . . . . . 53 6.3. RFC 3890: Bandwidth Modifier for SDP
7. rtcp-fb Attribute Analysis . . . . . . . . . . . . . . . . . 53 7. rtcp-fb Attribute Analysis
7.1. RFC4585: RTP/AVPF . . . . . . . . . . . . . . . . . . . . 53 7.1. RFC 4585: RTP/AVPF
7.2. RFC5104: Codec Control Messages in AVPF . . . . . . . . . 54 7.2. RFC 5104: Codec Control Messages in AVPF
7.3. RFC6285: Unicast-Based Rapid Acquisition of Multicast RTP 7.3. RFC 6285: Unicast-Based Rapid Acquisition of Multicast RTP
Sessions (RAMS) . . . . . . . . . . . . . . . . . . . . . 55 Sessions (RAMS)
7.4. RFC6679: ECN for RTP over UDP/IP . . . . . . . . . . . . 55 7.4. RFC 6679: ECN for RTP over UDP/IP
7.5. RFC6642: Third-Party Loss Report . . . . . . . . . . . . 56 7.5. RFC 6642: Third-Party Loss Report
7.6. RFC5104: Codec Control Messages in AVPF . . . . . . . . . 57 7.6. RFC 5104: Codec Control Messages in AVPF
8. group Attribute Analysis . . . . . . . . . . . . . . . . . . 57 8. group Attribute Analysis
8.1. RFC5888: SDP Grouping Framework . . . . . . . . . . . . . 57 8.1. RFC 5888: SDP Grouping Framework
8.2. RFC3524: Mapping Media Streams to Resource 8.2. RFC 3524: Mapping Media Streams to Resource Reservation
Reservation Flows . . . . . . . . . . . . . . . . . . . . 58 Flows
8.3. RFC4091: ANAT Semantics . . . . . . . . . . . . . . . . . 58 8.3. RFC 4091: ANAT Semantics
8.4. RFC5956: FEC Grouping Semantics in SDP . . . . . . . . . 58 8.4. RFC 5956: FEC Grouping Semantics in SDP
8.5. RFC5583: Signaling Media Decoding Dependency in SDP . . . 59 8.5. RFC 5583: Signaling Media Decoding Dependency in SDP
8.6. RFC7104: Duplication Grouping Semantics in the SDP . . . 59 8.6. RFC 7104: Duplication Grouping Semantics in the SDP
9. ssrc-group Attribute Analysis . . . . . . . . . . . . . . . . 60 9. ssrc-group Attribute Analysis
9.1. RFC5576: Source-Specific SDP Attributes . . . . . . . . . 60 9.1. RFC 5576: Source-Specific SDP Attributes
9.2. RFC7104: Duplication Grouping Semantics in the SDP . . . 60 9.2. RFC 7104: Duplication Grouping Semantics in the SDP
10. QoS Mechanism Token Analysis . . . . . . . . . . . . . . . . 61 10. QoS Mechanism Token Analysis
10.1. RFC5432: QoS Mechanism Selection in SDP . . . . . . . . 61 10.1. RFC 5432: QoS Mechanism Selection in SDP
11. k= Attribute Analysis . . . . . . . . . . . . . . . . . . . . 61 11. k= Attribute Analysis
11.1. RFC4566: SDP . . . . . . . . . . . . . . . . . . . . . . 62 11.1. RFC 4566: SDP
12. content Attribute Analysis . . . . . . . . . . . . . . . . . 62 12. content Attribute Analysis
12.1. RFC4796 . . . . . . . . . . . . . . . . . . . . . . . . 62 12.1. RFC 4796
12.2. 3GPP TS 24.182 . . . . . . . . . . . . . . . . . . . . . 63 12.2. 3GPP TS 24.182
12.3. 3GPP TS 24.183 . . . . . . . . . . . . . . . . . . . . . 63 12.3. 3GPP TS 24.183
13. Payload Formats . . . . . . . . . . . . . . . . . . . . . . . 63 13. Payload Formats
13.1. RFC5109: RTP Payload Format for Generic FEC . . . . . . 63 13.1. RFC 5109: RTP Payload Format for Generic FEC
14. Multiplexing Considerations for Encapsulating Attributes . . 64 14. Multiplexing Considerations for Encapsulating Attributes
14.1. RFC3407: cpar Attribute Analysis . . . . . . . . . . . . 64 14.1. RFC 3407: cpar Attribute Analysis
14.2. RFC5939 Analysis . . . . . . . . . . . . . . . . . . . . 65 14.2. RFC 5939 Analysis
14.2.1. Recommendation: Procedures for Potential 14.2.1. Recommendation: Procedures for Potential Configuration
Configuration Pairing . . . . . . . . . . . . . . . 66 Pairing
14.2.1.1. Example: Transport Capability Multiplexing . . . 67 14.3. RFC 6871 Analysis
14.2.1.2. Example: Attribute Capability Multiplexing . . . 68 14.3.1. Recommendation: Dealing with Payload Type Numbers
14.3. RFC6871 Analysis . . . . . . . . . . . . . . . . . . . . 68 14.3.2. Recommendation: Dealing with Latent Configurations
14.3.1. Recommendation: Dealing with Payload Type Numbers . 68 15. IANA Considerations
14.3.1.1. Example: Attribute Capability Under Shared 15.1. New "Multiplexing Categories" Subregistry
Payload Type . . . . . . . . . . . . . . . . . . 69 15.2. "Mux Category" Column for Subregistries
14.3.2. Recommendation: Dealing with Latent Configurations . 70 15.2.1. Table: SDP bwtype
15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 70 15.2.2. Table: attribute-name
15.1. New 'Multiplexing Categories' subregistry . . . . . . . 70 15.2.3. Table: content SDP Parameters
15.2. 'Mux Category' column for subregistries . . . . . . . . 71 15.2.4. Table: Semantics for the "group" SDP Attribute
15.2.1. Table: SDP bwtype . . . . . . . . . . . . . . . . . 72 15.2.5. Table: "rtcp-fb" Attribute Values
15.2.2. Table: att-field (session level) . . . . . . . . . . 72 15.2.6. Table: "ack" and "nack" Attribute Values
15.2.3. Table: att-field (both session and media level) . . 73 15.2.7. Table: "depend" SDP Attribute Values
15.2.4. Table: att-field (media level only) . . . . . . . . 75 15.2.8. Table: "cs-correlation" Attribute Values
15.2.5. Table: att-field (source level) . . . . . . . . . . 78 15.2.9. Table: Semantics for the "ssrc-group" SDP Attribute
15.2.6. Table: content SDP Parameters . . . . . . . . . . . 79 15.2.10. Table: SDP/RTSP Key Management Protocol Identifiers
15.2.7. Table: Semantics for the 'group' SDP Attribute . . . 79 15.2.11. Table: Codec Control Messages
15.2.8. Table: 'rtcp-fb' Attribute Values . . . . . . . . . 79 15.2.12. Table: QoS Mechanism Tokens
15.2.9. Table: 'ack' and 'nack' Attribute Values . . . . . . 80 15.2.13. Table: SDP Capability Negotiation Option Tags
15.2.10. Table: 'depend' SDP Attribute Values . . . . . . . . 80 15.2.14. Table: Timestamp Reference Clock Source Parameters
15.2.11. Table: 'cs-correlation' Attribute Values . . . . . . 81 15.2.15. Table: Media Clock Source Parameters
15.2.12. Table: Semantics for the 'ssrc-group' SDP Attribute 81 16. Security Considerations
15.2.13. Table: SDP/RTSP key management protocol identifiers 81 17. References
15.2.14. Table: Codec Control Messages . . . . . . . . . . . 82 17.1. Normative References
15.2.15. Table: QoS Mechanism Tokens . . . . . . . . . . . . 82 17.2. Informative References
15.2.16. Table: SDP Capability Negotiation Option Tags . . . 82 Acknowledgements
15.2.17. Table: Timestamp Reference Clock Source Parameters . 83 Author's Address
15.2.18. Table: Media Clock Source Parameters . . . . . . . . 83
16. Security Considerations . . . . . . . . . . . . . . . . . . . 83
17. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 83
18. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 84
19. References . . . . . . . . . . . . . . . . . . . . . . . . . 88
19.1. Normative References . . . . . . . . . . . . . . . . . . 88
19.2. Informative References . . . . . . . . . . . . . . . . . 88
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 96
1. Introduction 1. Introduction
SDP defines several attributes for capturing characteristics that SDP defines several attributes for capturing characteristics that
apply to the individual media descriptions (described by "m=" lines") apply to the individual media descriptions (described by "m=" lines)
and the overall multimedia session. Typically different media types and the overall multimedia session. Typically, different media types
(audio, video, etc.) described using different media descriptions (audio, video, etc.) described using different media descriptions
represent separate RTP sessions that are carried over individual represent separate RTP sessions that are carried over individual
transport layer flows. However transport-layer flows. However, [RFC8843] defines a way to use a
[I-D.ietf-mmusic-sdp-bundle-negotiation] defines a way to use a
single address:port combination (BUNDLE address) for receiving media single address:port combination (BUNDLE address) for receiving media
associated with multiple SDP media descriptions. This would, for associated with multiple SDP media descriptions. This would, for
example allow the usage of a single set of Interactive Connectivity example, allow the usage of a single set of Interactive Connectivity
Establishment (ICE) [RFC5245] candidates for multiple media Establishment (ICE) [RFC8445] candidates for multiple media
descriptions. This in turn has made it necessary to understand the descriptions. This, in turn, has made it necessary to understand the
interpretation and usage of the SDP attributes defined for the interpretation and usage of the SDP attributes defined for the
multiplexed media descriptions. multiplexed media descriptions.
Given the number of SDP attributes registered with the [IANA] and Given the number of SDP attributes registered with the [IANA] and the
possibility of new attributes being defined in the future, there is possibility of new attributes being defined in the future, there is
need for a framework to analyze these attributes for their need for a framework to analyze these attributes for their
applicability in the transport multiplexing use-cases. applicability in the transport multiplexing use cases.
The document starts with providing the motivation for requiring such The document starts with providing the motivation for requiring such
a framework. This is followed by introduction to the SDP attribute a framework. This is followed by introduction to the SDP attribute
analysis framework/procedures, following which several sections apply analysis framework and procedures, following which several sections
the framework to the SDP attributes registered with the [IANA]. apply the framework to the SDP attributes registered with the [IANA].
2. Terminology 2. Terminology
5-tuple: A collection of the following values: source address, source 5-tuple: A collection of the following values: source address,
port, destination address, destination port, and transport-layer source port, destination address, destination port, and transport-
protocol. layer protocol.
3GPP: Third Generation Partnership Project; see http://www.3gpp.org 3GPP: Third Generation Partnership Project; see
for more information about this organization. <https://www.3gpp.org> for more information about this
organization.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
document are to be interpreted as described in [RFC2119]. "OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Motivation 3. Motivation
The time and complications of setting up ICE [RFC5245] and Datagram An effort to reduce the number of necessary transport-level flows is
Transport Layer Security (DTLS) based Secure Real-time Transport required because of the time and complications involved in setting up
Protocol (SRTP) [RFC5763] transports for use by RTP, reasons to Secure Real-time Transport Protocol (SRTP) [RFC5763] transports for
conserve ports bindings on the Network Address Translators (NAT), use by RTP based on ICE [RFC8445] and Datagram Transport Layer
forms a requirement to try and reduce the number of transport level Security (DTLS). These procedures motivate conservation of ports
flows needed. This has resulted in the definition of ways, such as bindings on the Network Address Translators (NATs). This necessity
[I-D.ietf-mmusic-sdp-bundle-negotiation] to multiplex RTP over a has resulted in the definition of ways, such as that described in
single transport flow in order to preserve network resources such as [RFC8843], to multiplex RTP over a single transport flow in order to
port numbers. This imposes further restrictions on applicability of preserve network resources such as port numbers. This imposes
the SDP attributes as they are defined today. further restrictions on applicability of the SDP attributes as they
are defined today.
The specific problem is that there are attribute combinations which The specific problem is that there are attribute combinations that
make sense when specified on independent "m=" lines -- as with make sense when specified on independent "m=" lines -- as with
classical SDP -- that do not make sense when those "m=" lines are classical SDP -- that do not make sense when those "m=" lines are
then multiplexed over the same transport. To give an obvious then multiplexed over the same transport. To give an obvious
example, ICE permits each "m=" line to have an independently example, ICE permits each "m=" line to have an independently
specified ice-ufrag attribute. However, if the media from multiple specified "ice-ufrag" attribute. However, if the media from multiple
"m=" lines is multiplexed over the same ICE component, then the "m=" lines is multiplexed over the same ICE component, then the
meaning of media-level ice-ufrag attributes becomes muddled. meaning of media-level "ice-ufrag" attributes becomes muddled.
At the time of writing this document there are close to 250 SDP At the time of writing this document, there are close to 250 SDP
attributes registered with the [IANA] and more will be added in the attributes registered with the [IANA], and more will be added in the
future. There is no clearly defined procedure to establish the future. There is no clearly defined procedure to establish the
validity/applicability of these attributes when used with transport validity/applicability of these attributes when used with transport
multiplexing. multiplexing.
4. SDP Attribute Analysis Framework 4. SDP Attribute Analysis Framework
Attributes in an SDP session description can be defined at the Attributes in an SDP session description can be defined at the
session-level or media-level or source-level. Informally, there are session level, media level, or source level. Informally, there are
various semantic groupings for these attributes. One such grouping various semantic groupings for these attributes. One such grouping
could be notes as below: could be as follows:
o Attributes related to media content such as media type, encoding * Attributes related to media content such as media type, encoding
schemes and payload types. schemes, and payload types.
o Attributes specifying media transport characteristics like RTP/RTP * Attributes specifying media transport characteristics such as RTP/
Control Protocol (RTCP) port numbers, network addresses and QOS. RTP Control Protocol (RTCP) port numbers, network addresses, and
QoS.
o Metadata description attributes capturing session timing and * Metadata description attributes capturing session timing and
origin information. origin information.
o Attributes establishing relationships between media descriptions * Attributes establishing relationships between media descriptions,
such as grouping framework [RFC5888] such as grouping framework [RFC5888].
The proposed framework analyzes the SDP attributes usage under The proposed framework analyzes the SDP attributes usage under
multiplexing and assigns each SDP attribute to an appropriate multiplexing and assigns each SDP attribute to an appropriate
multiplexing category. Since the multiplexing categories defined in multiplexing category. Since the multiplexing categories defined in
this specification are independent of any informal semantic groupings this specification are independent of any informal semantic groupings
of the SDP attributes, the categorizations assigned are normative. of the SDP attributes, the categorizations assigned are normative.
4.1. Category: NORMAL 4.1. Category: NORMAL
The attributes in the NORMAL category can be independently specified The attributes in the NORMAL category can be independently specified
when multiplexed and they retain their original semantics. when multiplexed, and they retain their original semantics.
In the example given below, the direction and label attributes are In the example given below, the direction and label attributes are
independently specified for audio and video "m=" lines. These independently specified for audio and video "m=" lines. These
attributes are not impacted by multiplexing these media streams over attributes are not impacted by multiplexing these media streams over
a single transport layer flow. a single transport-layer flow.
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
m=audio 49172 RTP/AVP 99 m=audio 49172 RTP/AVP 99
a=sendonly a=sendonly
a=label:1 a=label:1
a=rtpmap:99 iLBC/8000 a=rtpmap:99 iLBC/8000
m=video 49172 RTP/AVP 31 m=video 49172 RTP/AVP 31
a=recvonly a=recvonly
a=label:2 a=label:2
a=rtpmap:31 H261/90000 a=rtpmap:31 H261/90000
4.2. Category: CAUTION 4.2. Category: CAUTION
The attributes in the CAUTION category are advised against It is not advisable to multiplex with the attributes in the CAUTION
multiplexing since their usage under multiplexing might lead to category, since their usage under multiplexing might lead to
incorrect behavior. incorrect behavior.
Example: Multiplexing media descriptions over a single Datagram Example: Multiplexing media descriptions over a single Datagram
Congestion Control Protocol (DCCP) transport [RFC5762] is not Congestion Control Protocol (DCCP) transport [RFC5762] is not
recommended since DCCP being a connection oriented protocol doesn't recommended, since DCCP is a connection-oriented protocol and
allow multiple connections on the same 5-tuple. therefore doesn't allow multiple connections on the same 5-tuple.
v=0 v=0
o=bob 2890844527 2890844527 IN IP4 client.biloxi.example.com o=bob 2890844527 2890844527 IN IP4 client.biloxi.example.com
s= s=
c=IN IP4 client.biloxi.example.com c=IN IP4 client.biloxi.example.com
t=0 0 t=0 0
m=video 5004 DCCP/RTP/AVP 99 m=video 5004 DCCP/RTP/AVP 99
a=rtpmap:99 h261/9000 a=rtpmap:99 h261/9000
a=dccp-service-code:SC=x52545056 a=dccp-service-code:SC=x52545056
a=setup:passive a=setup:passive
skipping to change at page 8, line 28 skipping to change at line 346
a=setup:passive a=setup:passive
a=connection:new a=connection:new
4.3. Category: IDENTICAL 4.3. Category: IDENTICAL
The attributes and their associated values (if any) in the IDENTICAL The attributes and their associated values (if any) in the IDENTICAL
category MUST be repeated across all the media descriptions under category MUST be repeated across all the media descriptions under
multiplexing. multiplexing.
Attributes such as rtcp-mux fall into this category. Since RTCP Attributes such as rtcp-mux fall into this category. Since RTCP
reporting is done per RTP session, RTCP Multiplexing MUST be enabled reporting is done per RTP session, RTCP multiplexing MUST be enabled
for both the audio and video "m=" lines if they are transported over for both the audio and video "m=" lines if they are transported over
a single 5-tuple. a single 5-tuple.
v=0 v=0
o=bob 2890844527 2890844527 IN IP4 client.biloxi.example.com o=bob 2890844527 2890844527 IN IP4 client.biloxi.example.com
s= s=
c=IN IP4 client.biloxi.example.com c=IN IP4 client.biloxi.example.com
t=0 0 t=0 0
m=audio 34567 RTP/AVP 97 m=audio 34567 RTP/AVP 97
a=rtcp-mux a=rtcp-mux
m=video 34567 RTP/AVP 31 m=video 34567 RTP/AVP 31
a=rtpmap:31 H261/90000 a=rtpmap:31 H261/90000
a=rtcp-mux a=rtcp-mux
Note: Eventhough IDENTICAL attributes must be repeated across all Note: Even though IDENTICAL attributes must be repeated across all
media descriptions under multiplexing, they might not always be media descriptions under multiplexing, they might not always be
explicitly encoded across all media descriptions. explicitly encoded across all media descriptions. [RFC8843] defines
[I-D.ietf-mmusic-sdp-bundle-negotiation] defines rules for when rules for when attributes and their values are implicitly applied to
attributes and their values are implicitly applied to media media description.
description.
4.4. Category: SUM 4.4. Category: SUM
The attributes in the SUM category can be set as they are normally The attributes in the SUM category can be set as they are normally
used but software using them in the multiplexing scenario MUST apply used, but software using them in the multiplexing scenario MUST apply
the sum of all the attributes being multiplexed instead of trying to the sum of all the attributes being multiplexed instead of trying to
use them independently. This is typically used for bandwidth or use them independently. This is typically used for bandwidth or
other rate limiting attributes to the underlying transport. other rate-limiting attributes to the underlying transport.
The software parsing the SDP sample below, should use the aggregate The software parsing the SDP sample below should use the aggregate
Application Specific (AS) bandwidth value from the individual media Application Specific (AS) bandwidth value from the individual media
descriptions to determine the AS value for the multiplexed session. descriptions to determine the AS value for the multiplexed session.
Thus the calculated AS value would be 256+64 kilobits per second for Thus the calculated AS value would be 256+64 kilobits per second for
the given example. the given example.
v=0 v=0
o=test 2890844526 2890842807 IN IP4 client.biloxi.example.com o=test 2890844526 2890842807 IN IP4 client.biloxi.example.com
c=IN IP4 client.biloxi.example.com c=IN IP4 client.biloxi.example.com
t=0 0 t=0 0
m=audio 49170 RTP/AVP 0 m=audio 49170 RTP/AVP 0
b=AS:64 b=AS:64
m=video 51372 RTP/AVP 31 m=video 51372 RTP/AVP 31
b=AS:256 b=AS:256
4.5. Category: TRANSPORT 4.5. Category: TRANSPORT
The attributes in the TRANSPORT category can be set normally for The attributes in the TRANSPORT category can be set normally for
multiple items in a multiplexed group but the software MUST pick the multiple items in a multiplexed group, but the software MUST pick the
one that's associated with the "m=" line whose information is used one that's associated with the "m=" line whose information is used
for setting up the underlying transport. for setting up the underlying transport.
In the example below, "a=crypto" attribute is defined for both the In the example below, the "a=crypto" attribute is defined for both
audio and the video "m=" lines. The video media line's a=crypto the audio and video "m=" lines. The video media line's "a=crypto"
attribute is chosen since its mid value (bar) appears first in the attribute is chosen since its MID value (bar) appears first in the
a=group:BUNDLE line. This is due to BUNDLE grouping semantic "a=group:BUNDLE" line. This is due to the BUNDLE grouping semantic
[I-D.ietf-mmusic-sdp-bundle-negotiation] which mandates the values [RFC8843], which mandates that the values from the "m=" line
from "m=" line corresponding to the mid appearing first on the corresponding to the mid appearing first on the "a=group:BUNDLE" line
a=group:BUNDLE line to be considered for setting up the RTP be considered for setting up the RTP transport.
Transport.
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
a=group:BUNDLE bar foo a=group:BUNDLE bar foo
m=audio 49172 RTP/AVP 99 m=audio 49172 RTP/AVP 99
a=mid:foo a=mid:foo
a=crypto:1 AES_CM_128_HMAC_SHA1_80 a=crypto:1 AES_CM_128_HMAC_SHA1_80
skipping to change at page 10, line 27 skipping to change at line 427
a=mid:bar a=mid:bar
a=crypto:1 AES_CM_128_HMAC_SHA1_80 a=crypto:1 AES_CM_128_HMAC_SHA1_80
inline:EcGZiNWpFJhQXdspcl1ekcmVCNWpVLcfHAwJSoj|2^20|1:32 inline:EcGZiNWpFJhQXdspcl1ekcmVCNWpVLcfHAwJSoj|2^20|1:32
a=rtpmap:96 H261/90000 a=rtpmap:96 H261/90000
4.6. Category: INHERIT 4.6. Category: INHERIT
The attributes in the INHERIT category encapsulate other SDP The attributes in the INHERIT category encapsulate other SDP
attributes or parameters. These attributes inherit their attributes or parameters. These attributes inherit their
multiplexing characteristics from the attributes or parameters they multiplexing characteristics from the attributes or parameters they
encapsulate. Such attributes are defined in [RFC3407], [RFC5939] and encapsulate. Such attributes are defined in [RFC3407], [RFC5939],
[RFC6871] as part of a generic framework for indicating and and [RFC6871] as part of a generic framework for indicating and
negotiating transport, media, and media format related capabilities negotiating capabilities in the SDP related to transport, media, and
in the SDP. media format.
The inheritance manifests itself when the encapsulated attribute or The inheritance manifests itself when the encapsulated attribute or
parameter is being leveraged. In the case of SDP Capability parameter is being leveraged. In the case of SDP Capability
Negotiation [RFC5939] for example, this occurs when a capability Negotiation [RFC5939], for example, this occurs when a capability
(encapsulating attribute) is used as part of a configuration; the (encapsulating attribute) is used as part of a configuration; the
configuration inherits the multiplexing category of each of its configuration inherits the multiplexing category of each of its
constituent (encapsulated) attributes and parameters. The inherited constituent (encapsulated) attributes and parameters. The inherited
attributes MUST be coherent in order to form a valid configuration attributes MUST be coherent in order to form a valid configuration
from a multiplexing point of view (see Section 14 for further from a multiplexing point of view (see Section 14 for further
details). details).
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
skipping to change at page 11, line 22 skipping to change at line 459
a=fmtp:100 max-fr=30;max-fs=8040 a=fmtp:100 max-fr=30;max-fs=8040
a=sqn: 0 a=sqn: 0
a=cdsc: 1 video RTP/AVP 100 a=cdsc: 1 video RTP/AVP 100
a=cpar: a=rtcp-mux a=cpar: a=rtcp-mux
m=video 3456 RTP/AVP 101 m=video 3456 RTP/AVP 101
a=rtpmap:101 VP8/90000 a=rtpmap:101 VP8/90000
a=fmtp:100 max-fr=15;max-fs=1200 a=fmtp:100 max-fr=15;max-fs=1200
a=cdsc: 2 video RTP/AVP 101 a=cdsc: 2 video RTP/AVP 101
a=cpar: a=rtcp-mux a=cpar: a=rtcp-mux
In the above example, the category IDENTICAL is inherited by the cpar In this example, the category IDENTICAL is inherited by the cpar-
encapsulated rtcp-mux attribute. encapsulated "rtcp-mux" attribute.
4.7. Category: IDENTICAL-PER-PT 4.7. Category: IDENTICAL-PER-PT
The attributes in the IDENTICAL-PER-PT category define the RTP The attributes in the IDENTICAL-PER-PT category define the RTP
payload configuration on per Payload Type basis and MUST have payload configuration on the basis of the payload type, and they MUST
identical values across all the media descriptions for a given RTP have identical values across all the media descriptions for a given
Payload Type when repeated. These Payload Types identify the same RTP payload type when repeated. These payload types identify the
codec configuration as defined in the Section 10.1.2 of same codec configuration as defined in Section 9.1 of [RFC8843] under
[I-D.ietf-mmusic-sdp-bundle-negotiation] under this context. this context.
In the SDP example below, Payload Types 96 and 97 are repeated across In the SDP example below, Payload Types 96 and 97 are repeated across
all the video "m=" lines and all the payload specific parameters (ex: all the video "m=" lines, and all the payload-specific parameters
rtpmap, fmtp) are identical (Note: some line breaks included are due (for example, rtpmap and fmtp) are identical. (Note: some line
to formatting only). breaks are due to formatting only.)
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
a=group:BUNDLE cam1 cam2 a=group:BUNDLE cam1 cam2
m=video 96 97 m=video 96 97
a=mid:cam1 a=mid:cam1
a=rtpmap:96 H264/90000 a=rtpmap:96 H264/90000
skipping to change at page 12, line 34 skipping to change at line 505
a=rtpmap:97 H264/90000 a=rtpmap:97 H264/90000
a=fmtp:97 profile-level-id=42400a; max-fs=240; max-fps=3000; a=fmtp:97 profile-level-id=42400a; max-fs=240; max-fps=3000;
max-mbps=7200; max-br=200 max-mbps=7200; max-br=200
4.8. Category: SPECIAL 4.8. Category: SPECIAL
For the attributes in the SPECIAL category, the text in the For the attributes in the SPECIAL category, the text in the
specification defining the attribute MUST be consulted for further specification defining the attribute MUST be consulted for further
handling when multiplexed. handling when multiplexed.
As an exampe, for the attribute extmap [RFC5285], the specification As an example, for the attribute "extmap" [RFC5285], the
defining the extension needs to be referred to understand the specification defining the extension needs to be consulted to
multiplexing implications. understand the multiplexing implications.
4.9. Category: TBD 4.9. Category: TBD
The attributes in the TBD category have not been analyzed under the The attributes in the TBD category have not been analyzed under the
proposed multiplexing framework and SHOULD NOT be multiplexed. proposed multiplexing framework and SHOULD NOT be multiplexed.
5. Analysis of Existing Attributes 5. Analysis of Existing Attributes
This section analyzes attributes listed in [IANA], grouped under the This section analyzes attributes listed in [IANA], grouped under the
IETF document that defines them. IETF document that defines them.
The "Level" column indicates whether the attribute is currently The "Level" column indicates whether the attribute is currently
specified as: specified as:
o S -- Session level * S -- Session level
o M -- Media level
o B -- Both (Implies either a session level or a media level * M -- Media level
* B -- Both (Implies either a session level or a media level
attribute) attribute)
o SR -- Source-level (for a single SSRC) [RFC5576] * SR -- Source-level (for a single SSRC) [RFC5576]
The "Mux Category" column identifies multiplexing category assigned The "Mux Category" column identifies the multiplexing category
per attribute and the "Notes" column captures additional informative assigned to each attribute, and the "Notes" column captures
details regarding the assigned category, wherever necessary. additional informative details regarding the assigned category,
wherever necessary.
5.1. RFC4566: SDP 5.1. RFC 4566: SDP
[RFC4566] defines SDP that is intended for describing multimedia [RFC4566] defines SDP that is intended for describing multimedia
sessions for the purposes of session announcement, session sessions for the purposes of session announcement, session
invitation, and other forms of multimedia session initiation. invitation, and other forms of multimedia session initiation.
+----------------+-----------------------+-------+------------------+ +================+=====================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------------+-----------------------+-------+------------------+ +================+=====================+=======+==================+
| sendrecv | Not impacted | B | NORMAL | | sendrecv | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| sendonly | Not impacted | B | NORMAL | | sendonly | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| recvonly | Not impacted | B | NORMAL | | recvonly | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| inactive | Not impacted | B | NORMAL | | inactive | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| cat | Not impacted | S | NORMAL | | cat | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| ptime | The attribute value | M | IDENTICAL-PER-PT | | ptime | The attribute value | M | IDENTICAL-PER-PT |
| | MUST be same for a | | | | | MUST be the same | | |
| | given codec | | | | | for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +----------------+---------------------+-------+------------------+
| maxptime | The attribute value | M | IDENTICAL-PER-PT | | maxptime | The attribute value | M | IDENTICAL-PER-PT |
| | MUST be same for a | | | | | MUST be the same | | |
| | given codec | | | | | for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +----------------+---------------------+-------+------------------+
| orient | Not Impacted | M | NORMAL | | orient | Not impacted | M | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| framerate | The attribute value | M | IDENTICAL-PER- | | framerate | The attribute value | M | IDENTICAL-PER-PT |
| | MUST be same for a | | PT | | | MUST be the same | | |
| | given codec | | | | | for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +----------------+---------------------+-------+------------------+
| quality | Not Impacted | M | NORMAL | | quality | Not impacted | M | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| rtpmap | The attribute value | M | IDENTICAL-PER-PT | | rtpmap | The attribute value | M | IDENTICAL-PER-PT |
| | MUST be same for a | | | | | MUST be the same | | |
| | given codec | | | | | for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +----------------+---------------------+-------+------------------+
| fmtp | The attribute value | M | IDENTICAL-PER-PT | | fmtp | The attribute value | M | IDENTICAL-PER-PT |
| | MUST be same for a | | | | | MUST be the same | | |
| | given codec | | | | | for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +----------------+---------------------+-------+------------------+
| keywds | Not impacted | S | NORMAL | | keywds | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type | Not Impacted | S | NORMAL | | type | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type:broadcast | Not Impacted | S | NORMAL | | type:broadcast | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type:H332 | Not Impacted | S | NORMAL | | type:H332 | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type:meeting | Not Impacted | S | NORMAL | | type:meeting | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type:moderated | Not Impacted | S | NORMAL | | type:moderated | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| type:test | Not Impacted | S | NORMAL | | type:test | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| tool | Not Impacted | S | NORMAL | | tool | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| charset | Not Impacted | S | NORMAL | | charset | Not impacted | S | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| sdplang | Not Impacted | B | NORMAL | | sdplang | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
| lang | Not Impacted | B | NORMAL | | lang | Not impacted | B | NORMAL |
| | | | | +----------------+---------------------+-------+------------------+
+----------------+-----------------------+-------+------------------+
5.1 RFC4566 Attribute Analysis Table 1: RFC 4566 Attribute Analysis
5.2. RFC4585: RTP/AVPF 5.2. RFC 4585: RTP/AVPF
[RFC4585] defines an extension to the Audio-visual Profile (AVP) that [RFC4585] defines an extension to the Audio-visual Profile (AVP) that
enables receivers to provide, statistically, more immediate feedback enables receivers to provide, statistically, more immediate feedback
to the senders and thus allows for short-term adaptation and to the senders and thus allows for short-term adaptation and
efficient feedback-based repair mechanisms to be implemented. efficient feedback-based repair mechanisms to be implemented.
+---------+------------------------------+-------+------------------+ +=========+===========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+------------------------------+-------+------------------+ +=========+===========================+=======+==================+
| rtcp- | Since RTCP feedback | M | IDENTICAL-PER- | | rtcp-fb | Since RTCP feedback | M | IDENTICAL-PER-PT |
| fb | attributes are Payload Type | | PT | | | attributes are scoped by | | |
| | (PT) scoped, their values | | | | | payload type (PT), their | | |
| | MUST be identical for a | | | | | values MUST be identical | | |
| | given PT across the | | | | | for a given PT across the | | |
| | multiplexed "m=" lines. | | | | | multiplexed "m=" lines. | | |
| | | | | +---------+---------------------------+-------+------------------+
+---------+------------------------------+-------+------------------+
5.2 RFC4585 Attribute Analysis Table 2: RFC 4585 Attribute Analysis
5.3. RFC5761: Multiplexing RTP and RTCP 5.3. RFC 5761: Multiplexing RTP and RTCP
[RFC5761] discusses issues that arise when multiplexing RTP data [RFC5761] discusses issues that arise when multiplexing RTP data
packets and RTP Control Protocol (RTCP) packets on a single UDP port. packets and RTP Control Protocol (RTCP) packets on a single UDP port.
It describes when such multiplexing is and is not appropriate, and it It describes when such multiplexing is and is not appropriate, and it
explains how the SDP can be used to signal multiplexed sessions. explains how the SDP can be used to signal multiplexed sessions.
+----------+------------------------------------+-------+-----------+ +==========+=================================+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+----------+------------------------------------+-------+-----------+ +==========+=================================+=======+==============+
| rtcp- | RTP and RTCP Multiplexing affects | M | IDENTICAL | | rtcp-mux | RTP and RTCP multiplexing | M | IDENTICAL |
| mux | the entire RTP session | | | | | affects the entire RTP session. | | |
| | | | | +----------+---------------------------------+-------+--------------+
+----------+------------------------------------+-------+-----------+
5.3 RFC5761 Attribute Analysis Table 3: RFC 5761 Attribute Analysis
5.4. RFC3312: Integration of Resource Management and SIP 5.4. RFC 3312: Integration of Resource Management and SIP
[RFC3312] defines a generic framework for preconditions, which are [RFC3312] defines a generic framework for preconditions, which are
extensible through IANA registration. This document also discusses extensible through IANA registration. This document also discusses
how network quality of service can be made a precondition for how network quality of service can be made a precondition for
establishment of sessions initiated by the Session Initiation establishment of sessions initiated by the Session Initiation
Protocol (SIP). These preconditions require that the participant Protocol (SIP). These preconditions require that the participant
reserve network resources before continuing with the session. reserve network resources before continuing with the session.
+-------+-----------------------+-------+--------------+ +======+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------+-----------------------+-------+--------------+ +======+======================+=======+==============+
| des | Refer to notes below | M | CAUTION | | des | Refer to notes below | M | CAUTION |
| | | | | +------+----------------------+-------+--------------+
| conf | Refer to notes below | M | CAUTION | | conf | Refer to notes below | M | CAUTION |
| | | | | +------+----------------------+-------+--------------+
| curr | Refer to notes below | M | CAUTION | | curr | Refer to notes below | M | CAUTION |
| | | | | +------+----------------------+-------+--------------+
+-------+-----------------------+-------+--------------+
5.4 RFC3312 Attribute Analysis Table 4: RFC 3312 Attribute Analysis
NOTE: A mismatched set of preconditions across media descriptions NOTE: A mismatched set of preconditions across media descriptions
results in Session establishment failures due to inability to meet results in session establishment failures due to inability to meet
right resource reservations requested. the requested resource reservations.
5.5. RFC4574: SDP Label Attribute 5.5. RFC 4574: SDP "label" Attribute
[RFC4574] defines a new SDP media-level attribute: "label". The [RFC4574] defines a new SDP media-level attribute: "label". The
"label" attribute carries a pointer to a media stream in the context "label" attribute carries a pointer to a media stream in the context
of an arbitrary network application that uses SDP. The sender of the of an arbitrary network application that uses SDP. The sender of the
SDP document can attach the "label" attribute to a particular media SDP document can attach the "label" attribute to a particular media
stream or streams. The application can then use the provided pointer stream or streams. The application can then use the provided pointer
to refer to each particular media stream in its context. to refer to each particular media stream in its context.
+--------+---------------+-------+--------------+ +=======+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------+---------------+-------+--------------+ +=======+==============+=======+==============+
| label | Not Impacted | M | NORMAL | | label | Not impacted | M | NORMAL |
| | | | | +-------+--------------+-------+--------------+
+--------+---------------+-------+--------------+
5.5 RFC4574 Attribute Analysis Table 5: RFC 4574 Attribute Analysis
5.6. RFC5432: QOS Mechanism Selection in SDP 5.6. RFC 5432: QoS Mechanism Selection in SDP
[RFC5432] defines procedures to negotiate QOS mechanisms using the [RFC5432] defines procedures for negotiating QoS mechanisms using the
SDP offer/answer model. SDP offer/answer model.
+----------------+-----------------------+-------+--------------+ +===============+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------------+-----------------------+-------+--------------+ +===============+======================+=======+==============+
| qos-mech-send | Refer to Section 10 | B | TRANSPORT | | qos-mech-send | Refer to Section 10. | B | TRANSPORT |
| | | | | +---------------+----------------------+-------+--------------+
| qos-mech-recv | Refer to Section 10 | B | TRANSPORT | | qos-mech-recv | Refer to Section 10. | B | TRANSPORT |
| | | | | +---------------+----------------------+-------+--------------+
+----------------+-----------------------+-------+--------------+
5.6 RFC5432 Attribute Analysis Table 6: RFC 5432 Attribute Analysis
5.7. RFC4568: SDP Security Descriptions 5.7. RFC 4568: SDP Security Descriptions
[RFC4568] defines a SDP cryptographic attribute for unicast media [RFC4568] defines an SDP cryptographic attribute for unicast media
streams. The attribute describes a cryptographic key and other streams. The attribute describes a cryptographic key and other
parameters that serve to configure security for a unicast media parameters that serve to configure security for a unicast media
stream in either a single message or a roundtrip exchange. stream in either a single message or a roundtrip exchange.
+--------+--------------------------------------+-------+-----------+ +========+=================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+--------+--------------------------------------+-------+-----------+ +========+=================================+=======+===========+
| crypto | crypto attribute MUST be the one | M | TRANSPORT | | crypto | crypto attribute MUST be the | M | TRANSPORT |
| | that corresponds to the "m=" line | | | | | one that corresponds to the | | |
| | chosen for setting up the underlying | | | | | "m=" line chosen for setting up | | |
| | transport flow | | | | | the underlying transport flow. | | |
| | | | | +--------+---------------------------------+-------+-----------+
+--------+--------------------------------------+-------+-----------+
5.7 RFC4568 Attribute Analysis Table 7: RFC 4568 Attribute Analysis
5.8. RFC5762: RTP over DCCP 5.8. RFC 5762: RTP over DCCP
RTP is a widely used transport for real-time multimedia on IP RTP is a widely used transport for real-time multimedia on IP
networks. DCCP is a transport protocol that provides desirable networks. DCCP is a transport protocol that provides desirable
services for real-time applications. [RFC5762] specifies a mapping services for real-time applications. [RFC5762] specifies a mapping
of RTP onto DCCP, along with associated signaling, such that real- of RTP onto DCCP, along with associated signaling, such that real-
time applications can make use of the services provided by DCCP. time applications can make use of the services provided by DCCP.
+-------------------+--------------------------+---------+----------+ +===================+======================+=========+==========+
| Name | Notes | Current | Mux | | Name | Notes | Current | Mux |
| | | | Category | | | | | Category |
+-------------------+--------------------------+---------+----------+ +===================+======================+=========+==========+
| dccp-service- | If RFC6773 is not being | M | CAUTION | | dccp-service-code | If RFC 6773 is not | M | CAUTION |
| code | used in addition to | | | | | being used in | | |
| | RFC5762, the port in the | | | | | addition to RFC5762, | | |
| | "m=" line is a DCCP | | | | | the port in the "m=" | | |
| | port. DCCP being a | | | | | line is a DCCP port. | | |
| | connection oriented | | | | | Being a connection- | | |
| | protocol does not allow | | | | | oriented protocol, | | |
| | multiple connections on | | | | | DCCP does not allow | | |
| | the same 5-tuple | | | | | multiple connections | | |
| | | | | | | on the same 5-tuple. | | |
+-------------------+--------------------------+---------+----------+ +-------------------+----------------------+---------+----------+
5.8 RFC5762 Attribute Analysis Table 8: RFC 5762 Attribute Analysis
NOTE: If RFC6773 is being used in addition to RFC5762 and provided NOTE: If RFC 6773 is being used in addition to RFC 5762, and the
that DCCP-in-UDP layer has additional demultiplexing, then it can be DCCP-in-UDP layer has additional demultiplexing, then it may be
possible to use different DCCP service codes for each DCCP flow, possible to use different DCCP service codes for each DCCP flow,
given each uses a different DCCP port. Although doing so might given each uses a different DCCP port. However, doing so might
conflict with the media type of the "m=" line. None of this is conflict with the media type of the "m=" line. None of this is
standardized yet and it wouldn't work as explained. Hence performing standardized yet, and it wouldn't work as explained. Hence
multiplexing is not recommended even in this alternate scenario. performing multiplexing is not recommended even in this alternate
scenario.
5.9. RFC6773: DCCP-UDP Encapsulation 5.9. RFC 6773: DCCP-UDP Encapsulation
[RFC6773] specifies an alternative encapsulation of DCCP, referred to [RFC6773] specifies an alternative encapsulation of DCCP, referred to
as DCCP-UDP. This encapsulation allows DCCP to be carried through as DCCP-UDP. This encapsulation allows DCCP to be carried through
the current generation of Network Address Translation (NAT) middle the current generation of Network Address Translation (NAT)
boxes without modification of those middle boxes. middleboxes without modification of those middleboxes.
+-----------+------------------------------------+-------+----------+ +===========+==============================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------+------------------------------------+-------+----------+ +===========+==============================+=======+==========+
| dccp- | Multiplexing is not recommended | M | CAUTION | | dccp-port | Multiplexing is not | M | CAUTION |
| port | due to potential conflict between | | | | | recommended due to potential | | |
| | the port used for DCCP | | | | | conflict between the port | | |
| | en/decapsulation and the RTP | | | | | used for DCCP encapsulation/ | | |
| | | | | | | decapsulation and the RTP. | | |
+-----------+------------------------------------+-------+----------+ +-----------+------------------------------+-------+----------+
5.9 RFC6773 Attribute Analysis Table 9: RFC 6773 Attribute Analysis
NOTE: RFC6773 is about tunneling DCCP in UDP, with the UDP port being NOTE: RFC 6773 allows DCCP-UDP encapsulation, with the UDP port being
the port of the DCCP en-/de-capsulation service. This encapsulation the port of the DCCP encapsulation/decapsulation service. This
allows arbitrary DCCP packets to be encapsulated and the DCCP port encapsulation allows arbitrary DCCP packets to be encapsulated, and
chosen can conflict with the port chosen for the RTP traffic. For the DCCP port chosen can conflict with the port chosen for the RTP
multiplexing several DCCP-in-UDP encapsulations on the same UDP port traffic. Multiplexing several DCCP-in-UDP encapsulations on the same
with no RTP traffic on the same port implies collapsing several DCCP UDP port with no RTP traffic on the same port implies collapsing
port spaces together. This can or cannot work depending on the several DCCP port spaces together. Whether or not this works depends
nature of DCCP encapsulation and ports choices thus rendering it to on the nature of DCCP encapsulation and ports choices; it is thus
be very application dependent. very application dependent.
5.10. RFC5506: Reduced-Size RTCP in RTP Profile 5.10. RFC 5506: Reduced-Size RTCP in RTP Profile
[RFC5506] discusses benefits and issues that arise when allowing RTCP [RFC5506] discusses benefits and issues that arise when allowing RTCP
packets to be transmitted with reduced size. packets to be transmitted with reduced size.
+------------+----------------------------------+-------+-----------+ +============+===========================+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux Category |
| | | | Category | +============+===========================+=======+==============+
+------------+----------------------------------+-------+-----------+ | rtcp-rsize | Reduced-size RTCP affects | M | IDENTICAL |
| rtcp- | Reduced size RTCP affects the | M | IDENTICAL | | | the entire RTP session. | | |
| rsize | entire RTP session | | | +------------+---------------------------+-------+--------------+
| | | | |
+------------+----------------------------------+-------+-----------+
5.10 RFC5506 Attribute Analysis Table 10: RFC 5506 Attribute Analysis
5.11. RFC6787: Media Resource Control Protocol Version 2 5.11. RFC 6787: Media Resource Control Protocol Version 2
The Media Resource Control Protocol Version 2 (MRCPv2) allows client The Media Resource Control Protocol Version 2 (MRCPv2) allows client
hosts to control media service resources such as speech synthesizers, hosts to control media service resources such as speech synthesizers,
recognizers, verifiers, and identifiers residing in servers on the recognizers, verifiers, and identifiers residing in servers on the
network. MRCPv2 is not a "stand-alone" protocol -- it relies on network. MRCPv2 is not a "stand-alone" protocol; it relies on other
other protocols, such as the SIP, to coordinate MRCPv2 clients and protocols, such as the SIP, to coordinate MRCPv2 clients and servers
servers, and manage session between them, and SDP to describe, and manage session between them, and SDP to describe, discover, and
discover, and exchange capabilities. It also depends on SIP and SDP exchange capabilities. It also depends on SIP and SDP to establish
to establish the media sessions and associated parameters between the the media sessions and associated parameters between the media source
media source or sink and the media server. Once this is done, the or sink and the media server. Once this is done, the MRCPv2 exchange
MRCPv2 exchange operates over the control session established above, operates over the control session established above, allowing the
allowing the client to control the media processing resources on the client to control the media-processing resources on the speech
speech resource server. [RFC6787] defines attributes for this resource server. [RFC6787] defines attributes for this purpose.
purpose.
+-----------+---------------+-------+--------------+ +==========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------+---------------+-------+--------------+ +==========+==============+=======+==============+
| resource | Not Impacted | M | NORMAL | | resource | Not impacted | M | NORMAL |
| | | | | +----------+--------------+-------+--------------+
| channel | Not Impacted | M | NORMAL | | channel | Not impacted | M | NORMAL |
| | | | | +----------+--------------+-------+--------------+
| cmid | Not Impacted | M | NORMAL | | cmid | Not impacted | M | NORMAL |
| | | | | +----------+--------------+-------+--------------+
+-----------+---------------+-------+--------------+
5.11 RFC6787 Attribute Analysis Table 11: RFC 6787 Attribute Analysis
5.12. RFC5245: ICE 5.12. RFC 8445: ICE
[RFC5245] describes a protocol for NAT traversal for UDP-based [RFC8445] describes a protocol for NAT traversal for UDP-based
multimedia sessions established with the offer/answer model. ICE multimedia sessions established with the offer/answer model. ICE
makes use of the Session Traversal Utilities for NAT (STUN) protocol makes use of the Session Traversal Utilities for NAT (STUN) protocol
and its extension, Traversal Using Relay NAT (TURN). ICE can be used and its extension, Traversal Using Relay NAT (TURN). ICE can be used
by any protocol utilizing the offer/answer model, such as the SIP. by any protocol utilizing the offer/answer model, such as the SIP.
+-------------------+---------------------------+-------+-----------+ +===================+===========================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+===================+===========================+=======+===========+
| ice-lite | Not impacted | S | NORMAL |
+-------------------+---------------------------+-------+-----------+
| ice-options | Not impacted | S | NORMAL |
+-------------------+---------------------------+-------+-----------+
| ice-mismatch | Not impacted | S | NORMAL |
+-------------------+---------------------------+-------+-----------+ +-------------------+---------------------------+-------+-----------+
| ice-lite | Not Impacted | S | NORMAL |
| | | | |
| ice-options | Not Impacted | S | NORMAL |
| | | | |
| ice-mismatch | Not Impacted | S | NORMAL |
| | | | |
| ice-pwd | ice-pwd MUST be the one | B | TRANSPORT | | ice-pwd | ice-pwd MUST be the one | B | TRANSPORT |
| | that corresponds to the | | | | | that corresponds to the | | |
| | "m=" line chosen for | | | | | "m=" line chosen for | | |
| | setting up the underlying | | | | | setting up the | | |
| | transport flow | | | | | underlying transport | | |
| | | | | | | flow. | | |
| ice-ufrag | ice-ufrag MUST be the one | B | TRANSPORT | +-------------------+---------------------------+-------+-----------+
| | that corresponds to the | | | | ice-ufrag | ice-ufrag MUST be the | B | TRANSPORT |
| | "m=" line chosen for | | |
| | setting up the underlying | | |
| | transport flow | | |
| | | | |
| candidate | ice candidate MUST be the | M | TRANSPORT |
| | one that corresponds to | | | | | one that corresponds to | | |
| | the "m=" line chosen for | | | | | the "m=" line chosen | | |
| | setting up the underlying | | | | | for setting up the | | |
| | transport flow | | | | | underlying transport | | |
| | | | | | | flow. | | |
| remote- | ice remote candidate MUST | M | TRANSPORT | +-------------------+---------------------------+-------+-----------+
| candidates | be the one that | | | | candidate | ice candidate MUST be | M | TRANSPORT |
| | the one that | | |
| | corresponds to the "m=" | | | | | corresponds to the "m=" | | |
| | line chosen for setting | | | | | line chosen for setting | | |
| | up the underlying | | | | | up the underlying | | |
| | transport flow | | | | | transport flow. | | |
| | | | | +-------------------+---------------------------+-------+-----------+
| remote-candidates | ice remote candidate | M | TRANSPORT |
| | MUST be the one that | | |
| | corresponds to the "m=" | | |
| | line chosen for setting | | |
| | up the underlying | | |
| | transport flow. | | |
+-------------------+---------------------------+-------+-----------+
| ice2 | Not impacted | S | NORMAL |
+-------------------+---------------------------+-------+-----------+ +-------------------+---------------------------+-------+-----------+
5.12 RFC5245 Attribute Analysis Table 12: RFC 8445 Attribute Analysis
5.13. RFC5285: RTP Header Extensions 5.13. RFC 5285: RTP Header Extensions
[RFC5285] provides a general mechanism to use the header extension [RFC5285] provides a general mechanism for using the header-extension
feature of RTP. It provides the option to use a small number of feature of RTP. (Note: [RFC5285] has been obsoleted by [RFC8285].)
small extensions in each RTP packet, where the universe of possible It provides the option to use a small number of small extensions in
extensions is large and registration is de-centralized. The actual each RTP packet, where the universe of possible extensions is large
extensions in use in a session are signaled in the setup information and registration is decentralized. The actual extensions in use in a
for that session. session are signaled in the setup information for that session.
+--------+---------------------------------------+-------+----------+ +========+================================+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux Category |
| | | | Category | +========+================================+=======+==============+
+--------+---------------------------------------+-------+----------+ | extmap | Refer to the document defining | B | SPECIAL |
| extmap | Refer to the document defining the | B | SPECIAL | | | the specific RTP extension. | | |
| | specific RTP Extension | | | +--------+--------------------------------+-------+--------------+
| | | | |
+--------+---------------------------------------+-------+----------+
5.13 RFC5285 Attribute Analysis Table 13: RFC 5285 Attribute Analysis
5.14. RFC3605: RTCP attribute in SDP 5.14. RFC 3605: RTCP Attribute in SDP
Originally, SDP assumed that RTP and RTCP were carried on consecutive Originally, SDP assumed that RTP and RTCP were carried on consecutive
ports. However, this is not always true when NATs are involved. ports. However, this is not always true when NATs are involved.
[RFC3605] specifies an early mechanism to indicate the RTCP port. [RFC3605] specifies an early mechanism for indicating the RTCP port.
+------+----------------------------------------+-------+-----------+ +======+================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+------+----------------------------------------+-------+-----------+ +======+================================+=======+===========+
| rtcp | RTCP Port MUST be the one that | M | TRANSPORT | | rtcp | RTCP port MUST be the one that | M | TRANSPORT |
| | corresponds to the "m=" line chosen | | | | | corresponds to the "m=" line | | |
| | for setting up the underlying | | | | | chosen for setting up the | | |
| | transport flow. | | | | | underlying transport flow. | | |
| | | | | +------+--------------------------------+-------+-----------+
+------+----------------------------------------+-------+-----------+
5.14 RFC3605 Attribute Analysis Table 14: RFC 3605 Attribute Analysis
5.15. RFC5576: Source-Specific SDP Attributes 5.15. RFC 5576: Source-Specific SDP Attributes
[RFC5576] defines a mechanism to describe RTP media sources, which [RFC5576] defines a mechanism for describing RTP media sources --
are identified by their synchronization source (SSRC) identifiers, in which are identified by their synchronization source (SSRC)
SDP, to associate attributes with these sources, and to express identifiers -- in SDP, to associate attributes with these sources and
relationships among sources. It also defines several source-level express relationships among sources. It also defines several source-
attributes that can be used to describe properties of media sources. level attributes that can be used to describe properties of media
sources.
+---------------+------------------------+-------+------------------+ +===============+=====================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------------+------------------------+-------+------------------+ +===============+=====================+=======+==================+
| ssrc | Refer to Notes below | M | NORMAL | | ssrc | Refer to notes | M | NORMAL |
| | | | | | | below. | | |
| ssrc-group | Refer to Section 9 for | M | NORMAL | +---------------+---------------------+-------+------------------+
| | specific analysis of | | | | ssrc-group | Refer to Section 9 | M | NORMAL |
| | the grouping | | | | | for specific | | |
| | semantics | | | | | analysis of the | | |
| | | | | | | grouping semantics. | | |
| cname | Not Impacted | SR | NORMAL | +---------------+---------------------+-------+------------------+
| | | | | | cname | Not impacted | SR | NORMAL |
| previous- | Refer to notes below | SR | NORMAL | +---------------+---------------------+-------+------------------+
| ssrc | | | | | previous-ssrc | Refer to notes | SR | NORMAL |
| | | | | | | below | | |
| fmtp | The attribute value | SR | IDENTICAL-PER- | +---------------+---------------------+-------+------------------+
| | MUST be same for a | | PT | | fmtp | The attribute value | SR | IDENTICAL-PER-PT |
| | given codec | | | | | MUST be the same | | |
| | configuration | | | | | for a given codec | | |
| | | | | | | configuration. | | |
+---------------+------------------------+-------+------------------+ +---------------+---------------------+-------+------------------+
5.15 RFC5576 Attribute Analysis Table 15: RFC 5576 Attribute Analysis
NOTE: If SSRCs are repeated across "m=" lines being multiplexed, they NOTE: If SSRCs are repeated across "m=" lines being multiplexed, they
MUST all represent the same underlying RTP Source. MUST all represent the same underlying RTP Source.
5.16. RFC7273: RTP Clock Source Signalling 5.16. RFC 7273: RTP Clock Source Signaling
[RFC7273] specifies SDP signalling that identifies timestamp [RFC7273] specifies SDP signaling that identifies timestamp reference
reference clock sources and SDP signalling that identifies the media clock sources and SDP signaling that identifies the media clock
clock sources in a multimedia session. sources in a multimedia session.
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| ts-refclk | Not Impacted | B | NORMAL | | ts-refclk | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| mediaclk | Not Impacted | B | NORMAL | | mediaclk | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:ntp | Not Impacted | B | NORMAL | | ts-refclk:ntp | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:ptp | Not Impacted | B | NORMAL | | ts-refclk:ptp | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:gps | Not Impacted | B | NORMAL | | ts-refclk:gps | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:gal | Not Impacted | B | NORMAL | | ts-refclk:gal | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:glonass | Not Impacted | B | NORMAL | | ts-refclk:glonass | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:local | Not Impacted | B | NORMAL | | ts-refclk:local | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ts-refclk:private | Not Impacted | B | NORMAL | | ts-refclk:private | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| mediaclk:sender | Not Impacted | B | NORMAL | | mediaclk:sender | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| mediaclk:direct | Not Impacted | B | NORMAL | | mediaclk:direct | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| mediaclk:IEEE1722 | Not Impacted | B | NORMAL | | mediaclk:IEEE1722 | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
+--------------------+---------------+-------+--------------+
5.16 RFC7273 Attribute Analysis Table 16: RFC 7273 Attribute Analysis
5.17. RFC6236: Image Attributes in SDP 5.17. RFC 6236: Image Attributes in SDP
[RFC6236] proposes a new generic session setup attribute to make it [RFC6236] proposes a new generic session setup attribute to make it
possible to negotiate different image attributes such as image size. possible to negotiate different image attributes, such as image size.
A possible use case is to make it possible for a low-end hand-held A possible use case is to make it possible for a low-end handheld
terminal to display video without the need to rescale the image, terminal to display video without the need to rescale the image,
something that may consume large amounts of memory and processing something that may consume large amounts of memory and processing
power. The document also helps to maintain an optimal bitrate for power. The document also helps to maintain an optimal bitrate for
video as only the image size that is desired by the receiver is video as only the image size that is desired by the receiver is
transmitted. transmitted.
+-----------+----------------------------+-------+------------------+ +===========+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------+----------------------------+-------+------------------+ +===========+==========================+=======+==================+
| imageattr | The attribute value MUST | M | IDENTICAL-PER- | | imageattr | The attribute value MUST | M | IDENTICAL-PER-PT |
| | be same for a given codec | | PT | | | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-----------+--------------------------+-------+------------------+
+-----------+----------------------------+-------+------------------+
5.17 RFC6236 Attribute Analysis Table 17: RFC 6236 Attribute Analysis
5.18. RFC7197: Duplication Delay Attribute in SDP 5.18. RFC 7197: Duplication Delay Attribute in SDP
[RFC7197] defines an attribute to indicate the presence of temporally [RFC7197] defines an attribute to indicate the presence of temporally
redundant media streams and the duplication delay in SDP. redundant media streams and the duplication delay in SDP.
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| duplication-delay | Not Impacted | B | NORMAL | | duplication-delay | Not impacted | B | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
+--------------------+---------------+-------+--------------+
5.18 RFC7197 Attribute Analysis Table 18: RFC 7197 Attribute Analysis
5.19. RFC7266: RTCP XR Blocks for MOS Metric Reporting 5.19. RFC 7266: RTCP XR Blocks for MOS Metric Reporting
[RFC7266] defines an RTCP Extended Report (XR) Block including two [RFC7266] defines an RTCP Extended Report (XR) Block that includes
new segment types and associated SDP parameters that allow the two new segment types and associated SDP parameters that allow the
reporting of mean opinion score (MOS) Metrics for use in a range of reporting of mean opinion score (MOS) metrics for use in a range of
RTP applications. RTP applications.
+-------------+---------------+-------+--------------+ +============+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------------+---------------+-------+--------------+ +============+==============+=======+==============+
| calgextmap | Not Impacted | B | NORMAL | | calgextmap | Not impacted | B | NORMAL |
| | | | | +------------+--------------+-------+--------------+
+-------------+---------------+-------+--------------+
5.19 RFC7266 Attribute Analysis Table 19: RFC 7266 Attribute Analysis
5.20. RFC6285: Rapid Acquisition of Multicast RTP Sessions 5.20. RFC 6285: Rapid Acquisition of Multicast RTP Sessions
[RFC6285] describes a method using the existing RTP and RTCP [RFC6285] describes a method of using the existing RTP and RTCP
machinery that reduces the acquisition delay. In this method, an machinery that reduces the acquisition delay. In this method, an
auxiliary unicast RTP session carrying the Reference Information to auxiliary unicast RTP session carrying the reference information to
the receiver precedes or accompanies the multicast stream. This the receiver precedes or accompanies the multicast stream. This
unicast RTP flow can be transmitted at a faster than natural bitrate unicast RTP flow can be transmitted at a faster-than-natural bitrate
to further accelerate the acquisition. The motivating use case for to further accelerate the acquisition. The motivating use case for
this capability is multicast applications that carry real-time this capability is multicast applications that carry real-time
compressed audio and video. compressed audio and video.
+---------------+------------------+-------+--------------+ +==============+=================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------------+------------------+-------+--------------+ +==============+=================+=======+==============+
| rams-updates | Not recommended | M | CAUTION | | rams-updates | Not recommended | M | CAUTION |
| | | | | +--------------+-----------------+-------+--------------+
+---------------+------------------+-------+--------------+
5.20 RFC6285 Attribute Analysis Table 20: RFC 6285 Attribute Analysis
5.21. RFC6230: Media Control Channel Framework 5.21. RFC 6230: Media Control Channel Framework
[RFC6230] describes a framework and protocol for application [RFC6230] describes a framework and protocol for application
deployment where the application programming logic and media deployment where the application programming logic and media
processing are distributed. This implies that application processing are distributed. This implies that application
programming logic can seamlessly gain access to appropriate resources programming logic can seamlessly gain access to appropriate resources
that are not co-located on the same physical network entity. The that are not co-located on the same physical network entity. The
framework uses SIP to establish an application-level control framework uses SIP to establish an application-level control
mechanism between application servers and associated external servers mechanism between application servers and associated external servers
such as media servers. such as media servers.
+---------+---------------+-------+--------------+ +========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+---------------+-------+--------------+ +========+==============+=======+==============+
| cfw-id | Not Impacted | M | NORMAL | | cfw-id | Not impacted | M | NORMAL |
| | | | | +--------+--------------+-------+--------------+
+---------+---------------+-------+--------------+
5.21 RFC6230 Attribute Analysis Table 21: RFC 6230 Attribute Analysis
5.22. RFC6364: SDP Elements for FEC Framework 5.22. RFC 6364: SDP Elements for FEC Framework
[RFC6364] specifies the use of SDP to describe the parameters [RFC6364] specifies the use of SDP to describe the parameters
required to signal the Forward Error Correction (FEC) Framework required to signal the Forward Error Correction (FEC) Framework
Configuration Information between the sender(s) and receiver(s). Configuration Information between the sender(s) and receiver(s).
This document also provides examples that show the semantics for This document also provides examples that show the semantics for
grouping multiple source and repair flows together for the grouping multiple source and repair flows together for the
applications that simultaneously use multiple instances of the FEC applications that simultaneously use multiple instances of the FEC
Framework. Framework.
+-----------------+------------------------------+-------+----------+ +=================+======================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------------+------------------------------+-------+----------+ +=================+======================+=======+==========+
| fec-source- | Refer to the document | M | SPECIAL | | fec-source-flow | Refer to the | M | SPECIAL |
| flow | defining specific FEC | | | | | document defining | | |
| | Scheme | | | | | specific FEC scheme. | | |
| | | | | +-----------------+----------------------+-------+----------+
| fec-repair- | Refer to the document | M | SPECIAL | | fec-repair-flow | Refer to the | M | SPECIAL |
| flow | defining specific FEC | | | | | document defining | | |
| | Scheme | | | | | specific FEC scheme. | | |
| | | | | +-----------------+----------------------+-------+----------+
| repair-window | Refer to the document | M | SPECIAL | | repair-window | Refer to the | M | SPECIAL |
| | defining specific FEC | | | | | document defining | | |
| | Scheme | | | | | specific FEC scheme. | | |
| | | | | +-----------------+----------------------+-------+----------+
+-----------------+------------------------------+-------+----------+
5.22 RFC6364 Attribute Analysis Table 22: RFC 6364 Attribute Analysis
5.23. RFC4796: Content Attribute 5.23. RFC 4796: "content" Attribute
[RFC4796] defines a new SDP media-level attribute, 'content'. The [RFC4796] defines a new SDP media-level attribute, "content". The
'content' attribute defines the content of the media stream to a more "content" attribute defines the content of the media stream to a more
detailed level than the media description line. The sender of an SDP detailed level than the media description line. The sender of an SDP
session description can attach the 'content' attribute to one or more session description can attach the "content" attribute to one or more
media streams. The receiving application can then treat each media media streams. The receiving application can then treat each media
stream differently (e.g., show it on a big or small screen) based on stream differently (e.g., show it on a big or small screen) based on
its content. its content.
+----------+---------------+-------+--------------+ +=========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------+---------------+-------+--------------+ +=========+==============+=======+==============+
| content | Not Impacted | M | NORMAL | | content | Not impacted | M | NORMAL |
| | | | | +---------+--------------+-------+--------------+
+----------+---------------+-------+--------------+
5.23 RFC4796 Attribute Analysis Table 23: RFC 4796 Attribute Analysis
5.24. RFC3407: SDP Simple Capability Declaration 5.24. RFC 3407: SDP Simple Capability Declaration
[RFC3407] defines a set of SDP attributes that enables SDP to provide [RFC3407] defines a set of SDP attributes that enables SDP to provide
a minimal and backwards compatible capability declaration mechanism. a minimal and backwards-compatible capability declaration mechanism.
+----------+------------------------+-------+--------------+ +=========+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------+------------------------+-------+--------------+ +=========+======================+=======+==============+
| sqn | Not Impacted | B | NORMAL | | sqn | Not impacted | B | NORMAL |
| | | | | +---------+----------------------+-------+--------------+
| cdsc | Not Impacted. | B | NORMAL | | cdsc | Not impacted | B | NORMAL |
| | | | | +---------+----------------------+-------+--------------+
| cpar | Refer to Section 14 | B | INHERIT | | cpar | Refer to Section 14 | B | INHERIT |
| | | | | +---------+----------------------+-------+--------------+
| cparmin | Refer to notes below | B | SPECIAL | | cparmin | Refer to notes below | B | SPECIAL |
| | | | | +---------+----------------------+-------+--------------+
| cparmax | Refer to notes below | B | SPECIAL | | cparmax | Refer to notes below | B | SPECIAL |
| | | | | +---------+----------------------+-------+--------------+
+----------+------------------------+-------+--------------+
5.24 RFC3407 Attribute Analysis Table 24: RFC 3407 Attribute Analysis
NOTE: The attributes (a=cparmin and a=cparmax) define minimum and NOTE: The attributes "a=cparmin" and "a=cparmax" define minimum and
maximum numerical values associated with the attributes described in maximum numerical values associated with the attributes described in
a=cpar. "a=cpar".
Since the cpar attribute can either define a 'b=' attribute or any Since the cpar attribute can either define a "b=" attribute or any
'a=' attribute, the multiplexing category depends on actual attribute "a=" attribute, the multiplexing category depends on the actual
being encapsulated and the implications of the numerical values attribute being encapsulated and the implications of the numerical
assigned. Hence it is recommended to consult the specification values assigned. Hence it is recommended to consult the
defining attributes (cparmin/cparmax) to further analyze their specification defining attributes "cparmin" and "cparmax" to further
behavior under multiplexing. analyze their behavior under multiplexing.
5.25. RFC6284: Port Mapping between Unicast and Multicast RTP Sessions 5.25. RFC 6284: Port Mapping between Unicast and Multicast RTP Sessions
[RFC6284] presents a port mapping solution that allows RTP receivers [RFC6284] presents a port-mapping solution that allows RTP receivers
to choose their own ports for an auxiliary unicast session in RTP to choose their own ports for an auxiliary unicast session in RTP
applications using both unicast and multicast services. The solution applications using both unicast and multicast services. The solution
provides protection against denial-of-service or packet amplification provides protection against denial-of-service or packet amplification
attacks that could be used to cause one or more RTP packets to be attacks that could be used to cause one or more RTP packets to be
sent to a victim client. sent to a victim client.
+-----------------+------------------------------+-------+----------+ +=================+=========================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------------+------------------------------+-------+----------+ +=================+=========================+=======+==========+
| portmapping- | Not recommended, if port | M | CAUTION | | portmapping-req | Not recommended if port | M | CAUTION |
| req | mapping is required by the | | | | | mapping is required by | | |
| | application | | | | | the application | | |
| | | | | +-----------------+-------------------------+-------+----------+
+-----------------+------------------------------+-------+----------+
5.25 RFC6284 Attribute Analysis Table 25: RFC 6284 Attribute Analysis
5.26. RFC6714: MSRP-CEMA 5.26. RFC 6714: MSRP-CEMA
[RFC6714] defines a Message Session Relay Protocol (MSRP) extension, [RFC6714] defines a Message Session Relay Protocol (MSRP) extension,
Connection Establishment for Media Anchoring (CEMA). Support of this Connection Establishment for Media Anchoring (CEMA). Support of this
extension is optional. The extension allows middle boxes to anchor extension is optional. The extension allows middleboxes to anchor
the MSRP connection, without the need for middle boxes to modify the the MSRP connection without the need for middleboxes to modify the
MSRP messages; thus, it also enables secure end-to-end MSRP MSRP messages; thus, it also enables secure end-to-end MSRP
communication in networks where such middle boxes are deployed. This communication in networks where such middleboxes are deployed. This
document also defines a SDP attribute, 'msrp-cema', that MSRP document also defines an SDP attribute, "msrp-cema", that MSRP
endpoints use to indicate support of the CEMA extension. endpoints use to indicate support of the CEMA extension.
+------------+-----------------------+-------+--------------+ +===========+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+-----------------------+-------+--------------+ +===========+======================+=======+==============+
| msrp-cema | Refer to notes below | M | TBD | | msrp-cema | Refer to notes below | M | TBD |
| | | | | +-----------+----------------------+-------+--------------+
+------------+-----------------------+-------+--------------+
5.26 RFC6714 Attribute Analysis Table 26: RFC 6714 Attribute Analysis
NOTE: As per section 9 of [I-D.ietf-mmusic-sdp-bundle-negotiation], NOTE: As per Section 9 of [RFC8843], there exists no publicly
there exists no publicly available specification that defines available specification that defines procedures for multiplexing/
procedures for multiplexing/demultiplexing MRSP flows over a single demultiplexing MSRP flows over a single 5-tuple. Once such a
5-tuple. Once such a specification is available, the multiplexing specification is available, the assignments of multiplexing
categories assignments for the attributes in this section could be categories for the attributes in this section could be revisited.
revisited.
5.27. RFC4583: SDP Format for BFCP Streams 5.27. RFC 4583: SDP Format for BFCP Streams
[RFC4583] document specifies how to describe Binary Floor Control [RFC4583] specifies how to describe Binary Floor Control Protocol
Protocol (BFCP) streams in SDP descriptions. User agents using the (BFCP) streams in SDP descriptions. User agents using the offer/
offer/answer model to establish BFCP streams use this format in their answer model to establish BFCP streams use this format in their
offers and answers. offers and answers.
+------------+-----------------------+-------+--------------+ +===========+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+-----------------------+-------+--------------+ +===========+======================+=======+==============+
| floorctrl | Refer to notes below | M | TBD | | floorctrl | Refer to notes below | M | TBD |
| | | | | +-----------+----------------------+-------+--------------+
| confid | Not Impacted | M | NORMAL | | confid | Refer to notes below | M | TBD |
| | | | | +-----------+----------------------+-------+--------------+
| userid | Not Impacted | M | NORMAL | | userid | Refer to notes below | M | TBD |
| | | | | +-----------+----------------------+-------+--------------+
| floorid | Not Impacted | M | NORMAL | | floorid | Refer to notes below | M | TBD |
| | | | | +-----------+----------------------+-------+--------------+
+------------+-----------------------+-------+--------------+
5.27 RFC4583 Attribute Analysis Table 27: RFC 4583 Attribute Analysis
NOTE: As per section 9 of [I-D.ietf-mmusic-sdp-bundle-negotiation], NOTE: [RFC4583] has been obsoleted by [RFC8856], which redefines the
there exists no publicly available specification that defines SDP attributes listed in this section, including the "Mux Category"
procedures for multiplexing/demultiplexing BFCP streams over a single values. However, [RFC8856] does not change the "Mux Category" values
5-tuple. Once such a specification is available, the multiplexing of the attributes.
categories assignments for the attributes in this section could be
revisited.
5.28. RFC5547: SDP Offer/Answer for File Transfer NOTE: As per Section 9 of [RFC8843], there exists no publicly
available specification that defines procedures for multiplexing/
demultiplexing BFCP streams over a single 5-tuple. Once such a
specification is available, the assignments of multiplexing
categories for the attributes in this section could be revisited.
5.28. RFC 5547: SDP Offer/Answer for File Transfer
[RFC5547] provides a mechanism to negotiate the transfer of one or [RFC5547] provides a mechanism to negotiate the transfer of one or
more files between two endpoints by using the SDP offer/answer model more files between two endpoints by using the SDP offer/answer model
specified in [RFC3264]. specified in [RFC3264].
+-------------------+-----------------------+-------+--------------+ +==================+======================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------------------+-----------------------+-------+--------------+ +==================+======================+=======+==============+
| file-selector | Refer to notes below | M | TBD | | file-selector | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
| file-transfer-id | Refer to notes below | M | TBD | | file-transfer-id | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
| file-disposition | Refer to notes below | M | TBD | | file-disposition | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
| file-date | Refer to notes below | M | TBD | | file-date | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
| file-icon | Refer to notes below | M | TBD | | file-icon | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
| file-range | Refer to notes below | M | TBD | | file-range | Refer to notes below | M | TBD |
| | | | | +------------------+----------------------+-------+--------------+
+-------------------+-----------------------+-------+--------------+
5.28 RFC5547 Attribute Analysis Table 28: RFC 5547 Attribute Analysis
NOTE: As per section 9 of [I-D.ietf-mmusic-sdp-bundle-negotiation], NOTE: As per Section 9 of [RFC8843], there exists no publicly
there exists no publicly available specification that defines available specification that defines procedures for multiplexing/
procedures for multiplexing/demultiplexing MRSP flows over a single demultiplexing MSRP flows over a single 5-tuple. Once such a
5-tuple. Once such a specification is available, the multiplexing specification is available, the assignments of multiplexing
categories assignments for attributes in this section could be categories for attributes in this section could be revisited.
revisited.
5.29. RFC6849: SDP and RTP Media Loopback Extension 5.29. RFC 6849: SDP and RTP Media Loopback Extension
[RFC6849] adds new SDP media types and attributes, which enable [RFC6849] adds new SDP media types and attributes that enable
establishment of media sessions where the media is looped back to the establishment of media sessions where the media is looped back to the
transmitter. Such media sessions will serve as monitoring and transmitter. Such media sessions will serve as monitoring and
troubleshooting tools by providing the means for measurement of more troubleshooting tools by providing the means for measurement of more
advanced Voice over IP (VoIP), Real-time Text, and Video over IP advanced Voice over IP (VoIP), real-time text, and Video over IP
performance metrics. performance metrics.
+--------------------+-------------------+-------+------------------+ +====================+================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------------------+-------------------+-------+------------------+ +====================+================+=======+==================+
| loopback rtp-pkt- | The attribute | M | IDENTICAL-PER- | | loopback rtp-pkt- | The attribute | M | IDENTICAL-PER-PT |
| loopback | value MUST be | | PT | | loopback | value MUST be | | |
| | same for a given | | | | | same for a | | |
| | codec | | | | | given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +--------------------+----------------+-------+------------------+
| loopback rtp- | The attribute | M | IDENTICAL-PER- | | loopback rtp- | The attribute | M | IDENTICAL-PER-PT |
| media-loopback | value MUST be | | PT | | media-loopback | value MUST be | | |
| | same for a given | | | | | same for a | | |
| | codec | | | | | given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +--------------------+----------------+-------+------------------+
| loopback-source | Not Impacted | M | NORMAL | | loopback-source | Not impacted | M | NORMAL |
| | | | | +--------------------+----------------+-------+------------------+
| loopback-mirror | Not Impacted | M | NORMAL | | loopback-mirror | Not impacted | M | NORMAL |
| | | | | +--------------------+----------------+-------+------------------+
+--------------------+-------------------+-------+------------------+
5.29 RFC6849 Analysis Table 29: RFC 6849 Analysis
5.30. RFC5760: RTCP with Unicast Feedback 5.30. RFC 5760: RTCP with Unicast Feedback
[RFC5760] specifies an extension to RTCP to use unicast feedback to a [RFC5760] specifies an extension to RTCP to use unicast feedback to a
multicast sender. The proposed extension is useful for single-source multicast sender. The proposed extension is useful for single-source
multicast sessions such as Source-Specific Multicast (SSM) multicast sessions such as source-specific multicast (SSM)
communication where the traditional model of many-to-many group communication where the traditional model of many-to-many group
communication is either not available or not desired. communication is either not available or not desired.
+--------------+--------------------------------+-------+-----------+ +==============+=========================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+--------------+--------------------------------+-------+-----------+ +==============+=========================+=======+===========+
| rtcp- | The attribute MUST be reported | M | IDENTICAL | | rtcp-unicast | The attribute MUST be | M | IDENTICAL |
| unicast | across all "m=" lines | | | | | reported across all | | |
| | multiplexed | | | | | multiplexed "m=" lines. | | |
| | | | | +--------------+-------------------------+-------+-----------+
+--------------+--------------------------------+-------+-----------+
5.30 RFC5760 Attribute Analysis Table 30: RFC 5760 Attribute Analysis
5.31. RFC3611: RTCP XR 5.31. RFC 3611: RTCP XR
[RFC3611] defines the Extended Report (XR) packet type for RTCP, and [RFC3611] defines the Extended Report (XR) packet type for RTCP and
defines how the use of XR packets can be signaled by an application defines how the use of XR packets can be signaled by an application
if it employs the Session Description Protocol (SDP). if it employs the Session Description Protocol (SDP).
+----------+---------------+-------+--------------+ +=========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------+---------------+-------+--------------+ +=========+==============+=======+==============+
| rtcp-xr | Not Impacted | B | NORMAL | | rtcp-xr | Not impacted | B | NORMAL |
| | | | | +---------+--------------+-------+--------------+
+----------+---------------+-------+--------------+
5.31 RFC3611 Attribute Analysis Table 31: RFC 3611 Attribute Analysis
5.32. RFC5939: SDP Capability Negotiation 5.32. RFC 5939: SDP Capability Negotiation
[RFC5939] defines a general SDP Capability Negotiation framework. It [RFC5939] defines a general SDP Capability Negotiation framework. It
also specifies how to provide attributes and transport protocols as also specifies how to provide attributes and transport protocols as
capabilities and negotiate them using the framework. Extensions for capabilities and negotiate them using the framework. Extensions for
other types of capabilities (e.g., media types and media formats) may other types of capabilities (e.g., media types and media formats) may
be provided in other documents. be provided in other documents.
+---------+-----------------------+-------+--------------+ +========+=====================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+-----------------------+-------+--------------+ +========+=====================+=======+==============+
| pcfg | Refer to Section 14 | M | SPECIAL | | pcfg | Refer to Section 14 | M | SPECIAL |
| | | | | +--------+---------------------+-------+--------------+
| acfg | Refer to Section 14 | M | SPECIAL | | acfg | Refer to Section 14 | M | SPECIAL |
| | | | | +--------+---------------------+-------+--------------+
| csup | Not Impacted | B | NORMAL | | csup | Not impacted | B | NORMAL |
| | | | | +--------+---------------------+-------+--------------+
| creq | Not Impacted | B | NORMAL | | creq | Not impacted | B | NORMAL |
| | | | | +--------+---------------------+-------+--------------+
| acap | Refer to Section 14 | B | INHERIT | | acap | Refer to Section 14 | B | INHERIT |
| | | | | +--------+---------------------+-------+--------------+
| tcap | Refer to Section 14 | B | INHERIT | | tcap | Refer to Section 14 | B | INHERIT |
| | | | | +--------+---------------------+-------+--------------+
| cap-v0 | Not Impacted | B | NORMAL | | cap-v0 | Not impacted | B | NORMAL |
| | | | | +--------+---------------------+-------+--------------+
+---------+-----------------------+-------+--------------+
5.32 RFC5939 Attribute Analysis Table 32: RFC 5939 Attribute Analysis
5.33. RFC6871: SDP Media Capabilities Negotiation 5.33. RFC 6871: SDP Media Capabilities Negotiation
SDP capability negotiation provides a general framework for SDP capability negotiation provides a general framework for
indicating and negotiating capabilities in SDP. The base framework indicating and negotiating capabilities in SDP. The base framework
defines only capabilities for negotiating transport protocols and only defines capabilities for negotiating transport protocols and
attributes. [RFC6871] extends the framework by defining media attributes. [RFC6871] extends the framework by defining media
capabilities that can be used to negotiate media types and their capabilities that can be used to negotiate media types and their
associated parameters. associated parameters.
+---------+-----------------------+-------+-------------------+ +========+======================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+-----------------------+-------+-------------------+ +========+======================+=======+==================+
| rmcap | Refer to Section 14 | B | IDENTICAL-PER-PT | | rmcap | Refer to Section 14 | B | IDENTICAL-PER-PT |
| | | | | +--------+----------------------+-------+------------------+
| omcap | Not Impacted | B | NORMAL | | omcap | Not impacted | B | NORMAL |
| | | | | +--------+----------------------+-------+------------------+
| mfcap | Refer to Section 14 | B | IDENTICAL-PER-PT | | mfcap | Refer to Section 14 | B | IDENTICAL-PER-PT |
| | | | | +--------+----------------------+-------+------------------+
| mscap | Refer to Section 14 | B | INHERIT | | mscap | Refer to Section 14 | B | INHERIT |
| | | | | +--------+----------------------+-------+------------------+
| lcfg | Refer to Section 14 | B | SPECIAL | | lcfg | Refer to Section 14 | B | SPECIAL |
| | | | | +--------+----------------------+-------+------------------+
| sescap | Refer to notes below | S | CAUTION | | sescap | Refer to notes below | S | CAUTION |
| | | | | +--------+----------------------+-------+------------------+
| med-v0 | Not Impacted | S | NORMAL | | med-v0 | Not impacted | S | NORMAL |
| | | | | +--------+----------------------+-------+------------------+
+---------+-----------------------+-------+-------------------+
5.33 RFC6871 - Attribute Analysis Table 33: RFC 6871 Attribute Analysis
NOTE: The "sescap" attribute is not recommended for use with NOTE: The "sescap" attribute is not recommended for use with
multiplexing. The reason is that it requires the use of unique multiplexing. The reason is that it requires the use of unique
configuration numbers across the entire SDP (per [RFC6871]) as configuration numbers across the entire SDP (per [RFC6871]) as
opposed to within a media description only (per [RFC5939]). As opposed to within a media description only (per [RFC5939]). As
described in Section 14, the use of identical configuration numbers described in Section 14, the use of identical configuration numbers
between multiplexed (bundled) media descriptions is the default way between multiplexed (bundled) media descriptions is the default way
of indicating compatible configurations in a bundle. of indicating compatible configurations in a bundle.
5.34. RFC7006: Miscellaneous Capabilities Negotiation SDP 5.34. RFC 7006: Miscellaneous Capabilities Negotiation in SDP
[RFC7006] extends the SDP capability negotiation framework to allow [RFC7006] extends the SDP Capability Negotiation framework to allow
endpoints to negotiate three additional SDP capabilities. In endpoints to negotiate three additional SDP capabilities. In
particular, this memo provides a mechanism to negotiate bandwidth particular, this memo provides a mechanism to negotiate bandwidth
("b=" line), connection data ("c=" line), and session or media titles ("b=" line), connection data ("c=" line), and session or media titles
("i=" line for each session or media). ("i=" line for each session or media).
+---------+-------------------------------------+-------+-----------+ +=========+==================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+---------+-------------------------------------+-------+-----------+ +=========+==================================+=======+===========+
| bcap | Inherit the category SUM as | B | INHERIT | | bcap | Inherit the category SUM as | B | INHERIT |
| | applicable to b= attribute | | | | | applicable to the "b=" attribute | | |
| | | | | +---------+----------------------------------+-------+-----------+
| bcap-v0 | Not Impacted | B | NORMAL | | bcap-v0 | Not impacted | B | NORMAL |
| | | | | +---------+----------------------------------+-------+-----------+
| ccap | The connection address type MUST be | B | IDENTICAL | | ccap | The connection address type MUST | B | IDENTICAL |
| | identical across all the | | | | | be identical across all the | | |
| | multiplexed "m=" lines | | | | | multiplexed "m=" lines. | | |
| | | | | +---------+----------------------------------+-------+-----------+
| ccap-v0 | Not Impacted | B | NORMAL | | ccap-v0 | Not impacted | B | NORMAL |
| | | | | +---------+----------------------------------+-------+-----------+
| icap | Not Impacted | B | NORMAL | | icap | Not impacted | B | NORMAL |
| | | | | +---------+----------------------------------+-------+-----------+
| icap-v0 | Not Impacted | B | NORMAL | | icap-v0 | Not impacted | B | NORMAL |
| | | | | +---------+----------------------------------+-------+-----------+
+---------+-------------------------------------+-------+-----------+
5.34 RFC7006 - Attribute Analysis Table 34: RFC 7006 Attribute Analysis
5.35. RFC4567: Key Management Extensions for SDP and RTSP 5.35. RFC 4567: Key Management Extensions for SDP and RTSP
[RFC4567] defines general extensions for SDP and Real Time Streaming [RFC4567] defines general extensions for SDP and Real-Time Streaming
Protocol (RTSP) to carry messages, as specified by a key management Protocol (RTSP) to carry messages, as specified by a key management
protocol, in order to secure the media. These extensions are protocol, in order to secure the media. These extensions are
presented as a framework, to be used by one or more key management presented as a framework to be used by one or more key management
protocols. As such, their use is meaningful only when complemented protocols. As such, their use is meaningful only when complemented
by an appropriate key management protocol. by an appropriate key management protocol.
+----------+------------------------------------+-------+-----------+ +==========+==========================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+----------+------------------------------------+-------+-----------+ +==========+==========================+=======+===========+
| key- | Key management protocol MUST be | B | IDENTICAL | | key-mgmt | Key management protocol | B | IDENTICAL |
| mgmt | identical across all the "m=" | | | | | MUST be identical across | | |
| | lines | | | | | all the "m=" lines. | | |
| | | | | +----------+--------------------------+-------+-----------+
| mikey | Key management protocol MUST be | B | IDENTICAL | | mikey | Key management protocol | B | IDENTICAL |
| | identical across all the "m=" | | | | | MUST be identical across | | |
| | lines | | | | | all the "m=" lines. | | |
| | | | | +----------+--------------------------+-------+-----------+
+----------+------------------------------------+-------+-----------+
5.35 RFC4567 Attribute Analysis Table 35: RFC 4567 Attribute Analysis
5.36. RFC4572: Comedia over TLS in SDP 5.36. RFC 4572: Comedia over TLS in SDP
[RFC4572] specifies how to establish secure connection-oriented media [RFC4572] specifies how to establish secure connection-oriented media
transport sessions over the Transport Layer Security (TLS) protocol transport sessions over the Transport Layer Security (TLS) protocol
using SDP. It defines a new SDP protocol identifier, 'TCP/TLS'. It using SDP. (Note: [RFC4572] has been obsoleted by [RFC8122].) It
also defines the syntax and semantics for an SDP 'fingerprint' defines a new SDP protocol identifier, "TCP/TLS". It also defines
attribute that identifies the certificate that will be presented for the syntax and semantics for an SDP "fingerprint" attribute that
the TLS session. This mechanism allows media transport over TLS identifies the certificate that will be presented for the TLS
connections to be established securely, so long as the integrity of session. This mechanism allows media transport over TLS connections
session descriptions is assured. to be established securely, so long as the integrity of session
descriptions is assured.
+-------------+---------------------------------+-------+-----------+ +=============+=================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-------------+---------------------------------+-------+-----------+ +=============+=================================+=======+===========+
| fingerprint | fingerprint value MUST be the | B | TRANSPORT | | fingerprint | fingerprint value MUST be | B | TRANSPORT |
| | one that corresponds to the | | | | | the one that corresponds | | |
| | "m=" line chosen for setting up | | | | | to the "m=" line chosen | | |
| | the underlying transport flow | | | | | for setting up the | | |
| | | | | | | underlying transport flow. | | |
+-------------+---------------------------------+-------+-----------+ +-------------+---------------------------------+-------+-----------+
5.36 RFC4572 Attribute Analysis Table 36: RFC 4572 Attribute Analysis
5.37. RFC4570: SDP Source Filters 5.37. RFC 4570: SDP Source Filters
[RFC4570] describes how to adapt SDP to express one or more source [RFC4570] describes how to adapt SDP to express one or more source
addresses as a source filter for one or more destination "connection" addresses as a source filter for one or more destination "connection"
addresses. It defines the syntax and semantics for an SDP "source- addresses. It defines the syntax and semantics for an SDP "source-
filter" attribute that may reference either IPv4 or IPv6 address(es) filter" attribute that may reference either IPv4 or IPv6 address(es)
as either an inclusive or exclusive source list for either multicast as either an inclusive or exclusive source list for either multicast
or unicast destinations. In particular, an inclusive source-filter or unicast destinations. In particular, an inclusive source filter
can be used to specify a Source-Specific Multicast (SSM) session. can be used to specify a source-specific multicast (SSM) session.
+---------------+-------------------------------+-------+-----------+ +===============+=========================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+---------------+-------------------------------+-------+-----------+ +===============+=========================+=======+===========+
| source- | The attribute MUST be | B | IDENTICAL | | source-filter | The attribute MUST be | B | IDENTICAL |
| filter | repeated across all "m=" | | | | | repeated across all | | |
| | lines multiplexed | | | | | multiplexed "m=" lines. | | |
| | | | | +---------------+-------------------------+-------+-----------+
+---------------+-------------------------------+-------+-----------+
5.37 RFC4570 Attribute Analysis Table 37: RFC 4570 Attribute Analysis
5.38. RFC6128: RTCP Port for Multicast Sessions 5.38. RFC 6128: RTCP Port for Multicast Sessions
SDP has an attribute that allows RTP applications to specify an SDP has an attribute that allows RTP applications to specify an
address and a port associated with the RTCP traffic. In RTP-based address and a port associated with the RTCP traffic. In RTP-based
source-specific multicast (SSM) sessions, the same attribute is used source-specific multicast (SSM) sessions, the same attribute is used
to designate the address and the RTCP port of the Feedback Target in to designate the address and the RTCP port of the Feedback Target in
the SDP description. However, the RTCP port associated with the SSM the SDP description. However, the RTCP port associated with the SSM
session itself cannot be specified by the same attribute to avoid session itself cannot be specified by the same attribute to avoid
ambiguity, and thus, is required to be derived from the "m=" line of ambiguity and thus is required to be derived from the "m=" line of
the media description. Deriving the RTCP port from the "m=" line the media description. Deriving the RTCP port from the "m=" line
imposes an unnecessary restriction. [RFC6128] removes this imposes an unnecessary restriction. [RFC6128] removes this
restriction by introducing a new SDP attribute. restriction by introducing a new SDP attribute.
+----------------+------------------------------+-------+-----------+ +================+==========================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+----------------+------------------------------+-------+-----------+ +================+==========================+=======+===========+
| multicast- | Multicast RTCP port MUST be | B | IDENTICAL | | multicast-rtcp | Multicast RTCP port MUST | B | IDENTICAL |
| rtcp | identical across all the | | | | | be identical across all | | |
| | "m=" lines | | | | | the "m=" lines. | | |
| | | | | +----------------+--------------------------+-------+-----------+
+----------------+------------------------------+-------+-----------+
5.38 RFC6128 Attribute Analysis Table 38: RFC 6128 Attribute Analysis
5.39. RFC6189: ZRTP 5.39. RFC 6189: ZRTP
[RFC6189] defines ZRTP, a protocol for media path Diffie-Hellman [RFC6189] defines ZRTP, a protocol for media path Diffie-Hellman
exchange to agree on a session key and parameters for establishing exchange to agree on a session key and parameters for establishing
unicast SRTP sessions for (VoIP applications. unicast SRTP sessions for VoIP applications.
+-----------+-----------------------------------+-------+-----------+ +===========+=================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------+-----------------------------------+-------+-----------+ +===========+=================================+=======+===========+
| zrtp- | zrtp-hash attribute MUST be the | M | TRANSPORT | | zrtp-hash | The zrtp-hash attribute MUST be | M | TRANSPORT |
| hash | one that corresponds to the "m=" | | | | | the one that corresponds to the | | |
| | line chosen for setting up the | | | | | "m=" line chosen for setting up | | |
| | underlying transport flow | | | | | the underlying transport flow. | | |
| | | | | +-----------+---------------------------------+-------+-----------+
+-----------+-----------------------------------+-------+-----------+
5.39 RFC6189 Attribute Analysis Table 39: RFC 6189 Attribute Analysis
5.40. RFC4145: Connection-Oriented Media 5.40. RFC 4145: Connection-Oriented Media
[RFC4145] describes how to express media transport over TCP using [RFC4145] describes how to express media transport over TCP using
SDP. It defines the SDP 'TCP' protocol identifier, the SDP 'setup' SDP. It defines the SDP "TCP" protocol identifier, the SDP "setup"
attribute, which describes the connection setup procedure, and the attribute, which describes the connection setup procedure, and the
SDP 'connection' attribute, which handles connection reestablishment. SDP "connection" attribute, which handles connection re-
establishment.
+------------+----------------------------------+-------+-----------+ +============+==================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+------------+----------------------------------+-------+-----------+ +============+==================================+=======+===========+
| setup | The setup attribute MUST be the | B | TRANSPORT | | setup | The setup attribute MUST be the | B | TRANSPORT |
| | one that corresponds to the "m=" | | | | | one that corresponds to the | | |
| | line chosen for setting up the | | |
| | underlying transport flow. | | |
| | | | |
| connection | The connection attribute MUST be | B | TRANSPORT |
| | the one that corresponds to the | | |
| | "m=" line chosen for setting up | | | | | "m=" line chosen for setting up | | |
| | the underlying transport flow. | | | | | the underlying transport flow. | | |
| | | | | +------------+----------------------------------+-------+-----------+
| connection | The connection attribute MUST | B | TRANSPORT |
| | be the one that corresponds to | | |
| | the "m=" line chosen for | | |
| | setting up the underlying | | |
| | transport flow. | | |
+------------+----------------------------------+-------+-----------+ +------------+----------------------------------+-------+-----------+
5.40 RFC4145 Attribute Analysis Table 40: RFC 4145 Attribute Analysis
5.41. RFC6947: The SDP altc Attribute 5.41. RFC 6947: The SDP "altc" Attribute
[RFC6947] proposes a mechanism that allows the same SDP offer to [RFC6947] proposes a mechanism that allows the same SDP offer to
carry multiple IP addresses of different address families (e.g., IPv4 carry multiple IP addresses of different address families (e.g., IPv4
and IPv6). The proposed attribute, the "altc" attribute, solves the and IPv6). The proposed "altc" attribute solves the backward-
backward-compatibility problem that plagued Alternative Network compatibility problem that plagued Alternative Network Address Types
Address Types (ANAT) due to their syntax. (ANAT) due to their syntax.
+------+----------------------------------------+-------+-----------+ +======+=================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+------+----------------------------------------+-------+-----------+ +======+=================================+=======+===========+
| altc | The IP Address and port MUST be the | M | TRANSPORT | | altc | The IP address and port MUST be | M | TRANSPORT |
| | one that corresponds to the "m=" line | | | | | the ones that correspond to the | | |
| | chosen for setting up the underlying | | | | | "m=" line chosen for setting up | | |
| | transport flow | | | | | the underlying transport flow. | | |
| | | | | +------+---------------------------------+-------+-----------+
+------+----------------------------------------+-------+-----------+
5.41 RFC6947 Attribute Analysis Table 41: RFC 6947 Attribute Analysis
5.42. RFC7195: SDP Extension for Circuit Switched Bearers in PSTN 5.42. RFC 7195: SDP Extension for Circuit-Switched Bearers in PSTN
[RFC7195] describes use cases, requirements, and protocol extensions [RFC7195] describes use cases, requirements, and protocol extensions
for using SDP offer/answer model for establishing audio and video for using the SDP offer/answer model for establishing audio and video
media streams over circuit-switched bearers in the Public Switched media streams over circuit-switched bearers in the Public Switched
Telephone Network (PSTN). Telephone Network (PSTN).
+-------------------------+-------------------+-------+-------------+ +=========================+=============+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux Category |
| | | | Category | +=========================+=============+=======+==============+
+-------------------------+-------------------+-------+-------------+ | cs-correlation:callerid | Refer to | M | TBD |
| cs- | Refer to notes | M | TBD | | | notes below | | |
| correlation:callerid | below | | | +-------------------------+-------------+-------+--------------+
| | | | | | cs-correlation:uuie | Refer to | M | TBD |
| cs-correlation:uuie | Refer to notes | M | TBD | | | notes below | | |
| | below | | | +-------------------------+-------------+-------+--------------+
| | | | | | cs-correlation:dtmf | Refer to | M | TBD |
| cs-correlation:dtmf | Refer to notes | M | TBD | | | notes below | | |
| | below | | | +-------------------------+-------------+-------+--------------+
| | | | | | cs-correlation:external | Refer to | M | TBD |
| cs- | Refer to notes | M | TBD | | | notes below | | |
| correlation:external | below | | | +-------------------------+-------------+-------+--------------+
| | | | |
+-------------------------+-------------------+-------+-------------+
5.42 RFC7195 Attribute Analysis Table 42: RFC 7195 Attribute Analysis
NOTE: [RFC7195] defines SDP attributes for establishing audio and NOTE: [RFC7195] defines SDP attributes for establishing audio and
video media streams over circuit-switched bearers by defining a new video media streams over circuit-switched bearers by defining a new
nettype value "PSTN". However, section 7.2 of nettype value, "PSTN". However, Section 7.2 of [RFC8843] requires
[I-D.ietf-mmusic-sdp-bundle-negotiation] requires the "c=" line the "c=" line nettype value to be "IN". If there exists in future a
nettype value of "IN". If in future there exists a specification specification that defines procedures to multiplex media streams over
that defines procedures to multiplex media streams over nettype nettype "PSTN", the multiplexing categories for attributes in this
"PSTN", the multiplexing categories for attributes in this section section could be revisited.
could be revisited.
5.43. RFC7272: IDMS Using the RTP Control Protocol (RTCP) 5.43. RFC 7272: IDMS Using the RTP Control Protocol (RTCP)
[RFC7272] defines a new RTCP Packet Type and an RTCP Extended Report [RFC7272] defines a new RTCP packet type and an RTCP Extended Report
(XR) Block Type to be used for achieving Inter-Destination Media (XR) Block Type to be used for achieving Inter-Destination Media
Synchronization (IDMS). Synchronization (IDMS).
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| rtcp-idms | Not Impacted | M | NORMAL | | rtcp-idms | Not impacted | M | NORMAL |
| | | | | +-----------+--------------+-------+--------------+
+------------+---------------+-------+--------------+
5.43 RFC7272 Attribute Analysis Table 43: RFC 7272 Attribute Analysis
5.44. RFC5159: Open Mobile Alliance (OMA) Broadcast (BCAST) SDP 5.44. RFC 5159: Open Mobile Alliance (OMA) Broadcast (BCAST) SDP
Attributes Attributes
[RFC5159] provides descriptions of SDP attributes used by the Open [RFC5159] provides descriptions of SDP attributes used by the Open
Mobile Alliance's Broadcast Service and Content Protection Mobile Alliance's "Service and Content Protection for Mobile
specification. Broadcast Services" specification.
+--------------------+-----------------------+-------+--------------+ +====================+===============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------------------+-----------------------+-------+--------------+ +====================+===============+=======+==============+
| bcastversion | Not Impacted | S | NORMAL | | bcastversion | Not impacted | S | NORMAL |
| | | | | +--------------------+---------------+-------+--------------+
| stkmstream | Not Impacted | B | NORMAL | | stkmstream | Not impacted | B | NORMAL |
| | | | | +--------------------+---------------+-------+--------------+
| SRTPAuthentication | Needs further | M | TBD | | SRTPAuthentication | Needs further | M | TBD |
| | analysis | | | | | analysis | | |
| | | | | +--------------------+---------------+-------+--------------+
| SRTPROCTxRate | Needs further | M | TBD | | SRTPROCTxRate | Needs further | M | TBD |
| | analysis | | | | | analysis | | |
| | | | | +--------------------+---------------+-------+--------------+
+--------------------+-----------------------+-------+--------------+
5.44 RFC5159 Attribute Analysis Table 44: RFC 5159 Attribute Analysis
5.45. RFC6193: Media Description for IKE in SDP 5.45. RFC 6193: Media Description for IKE in SDP
[RFC6193] specifies how to establish a media session that represents [RFC6193] specifies how to establish a media session that represents
a virtual private network using the Session Initiation Protocol for a virtual private network using the Session Initiation Protocol for
the purpose of on-demand media/application sharing between peers. It the purpose of on-demand media/application sharing between peers. It
extends the protocol identifier of SDP so that it can negotiate use extends the protocol identifier of SDP so that it can negotiate use
of the Internet Key Exchange Protocol (IKE) for media sessions in the of the Internet Key Exchange Protocol (IKE) for media sessions in the
SDP offer/answer model. SDP offer/answer model.
+------------------+-----------------------------+-------+----------+ +==================+============================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+------------------+-----------------------------+-------+----------+ +==================+============================+=======+==========+
| ike-setup | Unlikely to use IKE in the | B | CAUTION | | ike-setup | Unlikely to use IKE in the | B | CAUTION |
| | context of multiplexing | | | | | context of multiplexing | | |
| | | | | +------------------+----------------------------+-------+----------+
| psk-fingerprint | Unlikely to use IKE in the | B | CAUTION | | psk-fingerprint | Unlikely to use IKE in the | B | CAUTION |
| | context of multiplexing | | | | | context of multiplexing | | |
| | | | | +------------------+----------------------------+-------+----------+
| ike-esp | Unlikely to use IKE in the | B | CAUTION | | ike-esp | Unlikely to use IKE in the | B | CAUTION |
| | context of multiplexing | | | | | context of multiplexing | | |
| | | | | +------------------+----------------------------+-------+----------+
| ike-esp- | Unlikely to use IKE in the | B | CAUTION | | ike-esp-udpencap | Unlikely to use IKE in the | B | CAUTION |
| udpencap | context of multiplexing | | | | | context of multiplexing | | |
| | | | | +------------------+----------------------------+-------+----------+
+------------------+-----------------------------+-------+----------+
5.45 RFC6193 Attribute Analysis Table 45: RFC 6193 Attribute Analysis
5.46. RFC2326: Real Time Streaming Protocol 5.46. RFC 2326: Real Time Streaming Protocol
The Real Time Streaming Protocol, or RTSP, is an application-level The Real Time Streaming Protocol, or RTSP, is an application-level
protocol for control over the delivery of data with real-time protocol for control over the delivery of data with real-time
properties. RTSP provides an extensible framework to enable properties. RTSP provides an extensible framework to enable
controlled, on-demand delivery of real-time data, such as audio and controlled, on-demand delivery of real-time data, such as audio and
video. video.
+---------+-------------------------------------+-------+-----------+ +=========+=======================+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux Category |
| | | | Category | +=========+=======================+=======+==============+
+---------+-------------------------------------+-------+-----------+ | etag | RFC 2326 is obsolete. | B | CAUTION |
| etag | RTSP is not supported for RTP | B | CAUTION | +---------+-----------------------+-------+--------------+
| | Stream multiplexing | | | | range | RFC 2326 is obsolete. | B | CAUTION |
| | | | | +---------+-----------------------+-------+--------------+
| range | RTSP is not supported for RTP | B | CAUTION | | control | RFC 2326 is obsolete. | B | CAUTION |
| | Stream multiplexing | | | +---------+-----------------------+-------+--------------+
| | | | | | mtag | RFC 2326 is obsolete. | B | CAUTION |
| control | RTSP is not supported for RTP | B | CAUTION | +---------+-----------------------+-------+--------------+
| | Stream multiplexing | | |
| | | | |
| mtag | RTSP is not supported for RTP | B | CAUTION |
| | Stream multiplexing | | |
| | | | |
+---------+-------------------------------------+-------+-----------+
5.46 RFC2326 Attribute Analysis Table 46: RFC 2326 Attribute Analysis
NOTE: [RFC2326] defines SDP attributes that are applicable in the NOTE: [RFC2326] defines SDP attributes that are applicable in the
declarative usage of SDP alone. For purposes of this document, only declarative usage of SDP alone. For the purposes of this document,
the Offer/Answer usage of SDP is considered as mandated by only the offer/answer usage of SDP is considered to be mandated by
[I-D.ietf-mmusic-sdp-bundle-negotiation]. [RFC8843].
5.47. RFC6064: SDP and RTSP Extensions for 3GPP 5.47. RFC 7826: Real-Time Streaming Protocol
The Real-Time Streaming Protocol, or RTSP, is an application-level
protocol for control over the delivery of data with real-time
properties. RTSP provides an extensible framework to enable
controlled, on-demand delivery of real-time data, such as audio and
video.
+=========+===========================+=======+==============+
| Name | Notes | Level | Mux Category |
+=========+===========================+=======+==============+
| range | RTSP is not supported for | B | CAUTION |
| | RTP stream multiplexing. | | |
+---------+---------------------------+-------+--------------+
| control | RTSP is not supported for | B | CAUTION |
| | RTP stream multiplexing. | | |
+---------+---------------------------+-------+--------------+
| mtag | RTSP is not supported for | B | CAUTION |
| | RTP stream multiplexing. | | |
+---------+---------------------------+-------+--------------+
Table 47: RFC 7826 Attribute Analysis
NOTE: [RFC7826] defines SDP attributes that are applicable in the
declarative usage of SDP alone. For the purposes of this document,
only the offer/answer usage of SDP is considered to be mandated by
[RFC8843].
5.48. RFC 6064: SDP and RTSP Extensions for 3GPP
The Packet-switched Streaming Service (PSS) and the Multimedia The Packet-switched Streaming Service (PSS) and the Multimedia
Broadcast/Multicast Service (MBMS) defined by 3GPP use SDP and RTSP Broadcast/Multicast Service (MBMS) defined by 3GPP use SDP and RTSP
with some extensions. [RFC6064] provides information about these with some extensions. [RFC6064] provides information about these
extensions and registers the RTSP and SDP extensions with IANA. extensions and registers the RTSP and SDP extensions with IANA.
+--------------------------------+---------------+-------+----------+ +==============================+=============+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+--------------------------------+---------------+-------+----------+ +==============================+=============+=======+==============+
| X-predecbufsize | Refer to | M | CAUTION | | X-predecbufsize | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| X-initpredecbufperiod | Refer to | M | CAUTION | | X-initpredecbufperiod | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| X-initpostdecbufperiod | Refer to | M | CAUTION | | X-initpostdecbufperiod | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| X-decbyterate | Refer to | M | CAUTION | | X-decbyterate | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3gpp-videopostdecbufsize | Refer to | M | CAUTION | | 3gpp-videopostdecbufsize | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| framesize | Refer to | M | CAUTION | | framesize | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-Integrity-Key | Refer to | S | CAUTION | | 3GPP-Integrity-Key | Refer to | S | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-SDP-Auth | Refer to | S | CAUTION | | 3GPP-SDP-Auth | Refer to | S | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-SRTP-Config | Refer to | M | CAUTION | | 3GPP-SRTP-Config | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| alt | Refer to | M | CAUTION | | alt | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| alt-default-id | Refer to | M | CAUTION | | alt-default-id | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| alt-group | Refer to | S | CAUTION | | alt-group | Refer to | S | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-Adaptation-Support | Refer to | M | CAUTION | | 3GPP-Adaptation-Support | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-Asset-Information | Refer to | B | CAUTION | | 3GPP-Asset-Information | Refer to | B | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| mbms-mode | Refer to | B | CAUTION | | mbms-mode | Refer to | B | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| mbms-flowid | Refer to | M | CAUTION | | mbms-flowid | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| mbms-repair | Refer to | B | CAUTION | | mbms-repair | Refer to | B | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics | Refer to | M | CAUTION | | 3GPP-QoE-Metrics | Refer to | M | CAUTION |
| | notes below | | | | | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Corruption | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Corruption | Refer to | M | CAUTION |
| duration | notes below | | | | duration | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Rebuffering | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Rebuffering | Refer to | M | CAUTION |
| duration | notes below | | | | duration | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Initial | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Initial | Refer to | M | CAUTION |
| buffering duration | notes below | | | | buffering duration | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Successive | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Successive | Refer to | M | CAUTION |
| loss of RTP packets | notes below | | | | loss of RTP packets | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Frame rate | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Frame rate | Refer to | M | CAUTION |
| deviation | notes below | | | | deviation | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Jitter | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Jitter | Refer to | M | CAUTION |
| duration | notes below | | | | duration | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Content | Refer to | B | CAUTION | | 3GPP-QoE-Metrics:Content | Refer to | B | CAUTION |
| Switch Time | notes below | | | | Switch Time | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Average Codec | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Average | Refer to | M | CAUTION |
| Bitrate | notes below | | | | Codec Bitrate | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Codec | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Codec | Refer to | M | CAUTION |
| Information | notes below | | | | Information | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
| 3GPP-QoE-Metrics:Buffer | Refer to | M | CAUTION | | 3GPP-QoE-Metrics:Buffer | Refer to | M | CAUTION |
| Status | notes below | | | | Status | notes below | | |
| | | | | +------------------------------+-------------+-------+--------------+
+--------------------------------+---------------+-------+----------+
5.47 RFC6064 Attribute Analysis Table 48: RFC 6064 Attribute Analysis
NOTE: [RFC6064] defines SDP attributes that are applicable in the NOTE: [RFC6064] defines SDP attributes that are applicable in the
declarative usage of SDP alone. For purposes of this document, only declarative usage of SDP alone. For the purposes of this document,
the Offer/Answer usage of SDP is considered as mandated by only the offer/answer usage of SDP is considered to be mandated by
[I-D.ietf-mmusic-sdp-bundle-negotiation]. [RFC8843].
5.48. RFC3108: ATM SDP 5.49. RFC 3108: ATM SDP
[RFC3108] describes conventions for using SDP described for [RFC3108] describes conventions for using SDP described for
controlling ATM Bearer Connections, and any associated ATM Adaptation controlling ATM bearer connections and any associated ATM Adaptation
Layer (AAL). Layer (AAL).
+-----------------------+--------------------+-------+--------------+ +=======================+=============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------------------+--------------------+-------+--------------+ +=======================+=============+=======+==============+
| aalType | Refer to notes | B | CAUTION | | aalType | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| eecid | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | eecid | Refer to | B | CAUTION |
| capability | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| qosClass | Refer to notes | B | CAUTION | | capability | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| bcob | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | qosClass | Refer to | B | CAUTION |
| stc | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| upcc | Refer to notes | B | CAUTION | | bcob | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| atmQOSparms | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | stc | Refer to | B | CAUTION |
| atmTrfcDesc | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| abrParms | Refer to notes | B | CAUTION | | upcc | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| abrSetup | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | atmQOSparms | Refer to | B | CAUTION |
| bearerType | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| lij | Refer to notes | B | CAUTION | | atmTrfcDesc | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| anycast | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | abrParms | Refer to | B | CAUTION |
| cache | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| bearerSigIE | Refer to notes | B | CAUTION | | abrSetup | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| aalApp | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | bearerType | Refer to | B | CAUTION |
| cbrRate | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| sbc | Refer to notes | B | CAUTION | | lij | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| clkrec | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | anycast | Refer to | B | CAUTION |
| fec | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| prtfl | Refer to notes | B | CAUTION | | cache | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| structure | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | bearerSigIE | Refer to | B | CAUTION |
| cpsSDUsize | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| aal2CPS | Refer to notes | B | CAUTION | | aalApp | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| aal2CPSSDUrate | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | cbrRate | Refer to | B | CAUTION |
| aal2sscs3661unassured | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| aal2sscs3661assured | Refer to notes | B | CAUTION | | sbc | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| aal2sscs3662 | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | clkrec | Refer to | B | CAUTION |
| aal5sscop | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| atmmap | Refer to notes | B | CAUTION | | fec | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| silenceSupp | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | prtfl | Refer to | B | CAUTION |
| ecan | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| gc | Refer to notes | B | CAUTION | | structure | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| profileDesc | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | cpsSDUsize | Refer to | B | CAUTION |
| vsel | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| dsel | Refer to notes | B | CAUTION | | aal2CPS | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| fsel | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | aal2CPSSDUrate | Refer to | B | CAUTION |
| onewaySel | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| codecconfig | Refer to notes | B | CAUTION | | aal2sscs3661unassured | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| isup_usi | Refer to notes | B | CAUTION | +-----------------------+-------------+-------+--------------+
| | below | | | | aal2sscs3661assured | Refer to | B | CAUTION |
| uiLayer1_Prot | Refer to notes | B | CAUTION | | | notes below | | |
| | below | | | +-----------------------+-------------+-------+--------------+
| chain | Refer to notes | B | CAUTION | | aal2sscs3662 | Refer to | B | CAUTION |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
+-----------------------+--------------------+-------+--------------+ | aal5sscop | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| atmmap | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| silenceSupp | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| ecan | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| gc | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| profileDesc | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| vsel | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| dsel | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| fsel | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| onewaySel | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| codecconfig | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| isup_usi | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| uiLayer1_Prot | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
| chain | Refer to | B | CAUTION |
| | notes below | | |
+-----------------------+-------------+-------+--------------+
5.48 RFC3108 Attribute Analysis Table 49: RFC 3108 Attribute Analysis
NOTE: RFC3108 describes conventions for using SDP for characterizing NOTE: RFC 3108 describes conventions for using SDP for characterizing
ATM bearer connections using an AAL1, AAL2 or AAL5 adaptation layers. ATM bearer connections using an AAL1, AAL2, or AAL5 adaptation layer.
For AAL1, AAL2 and AAL5, bearer connections can be used to transport For AAL1, AAL2, and AAL5, bearer connections can be used to transport
single media streams. In addition, for AAL1 and AAL2, multiple media single media streams. In addition, for AAL1 and AAL2, multiple media
streams can be multiplexed into a bearer connection. For all streams can be multiplexed into a bearer connection. For all
adaptation types (AAL1, AAL2 and AAL5), bearer connections can be adaptation types (AAL1, AAL2, and AAL5), bearer connections can be
bundled into a single media group. In all cases addressed by bundled into a single media group. In all cases addressed by RFC
RFC3108, a real-time media stream (voice, video, voiceband data, 3108, a real-time media stream (voice, video, voiceband data,
pseudo-wire, and others) or a multiplex of media streams is mapped pseudowire, and others) or a multiplex of media streams is mapped
directly into an ATM connection. RFC3108 does not address cases directly into an ATM connection. RFC 3108 does not address cases
where ATM serves as a low-level transport pipe for IP packets which where ATM serves as a low-level transport pipe for IP packets that
in turn can carry one or more real-time (e.g. VoIP) media sessions can, in turn, carry one or more real-time (e.g., VoIP) media sessions
with a life-cycle different from that of the underlying ATM with a life cycle different from that of the underlying ATM
transport. transport.
5.49. 3GPP TS 26.114
[R3GPPTS26.114] specifies IP multimedia subsystem: Media handling and
interaction
+---------------------+--------------------------+-------+----------+
| Name | Notes | Level | Mux |
| | | | Category |
+---------------------+--------------------------+-------+----------+
| 3gpp_sync_info | Usage defined for the IP | M | NORMAL |
| | Multimedia Subsystem | | |
| | | | |
| 3gpp_MaxRecvSDUSize | Usage defined for the IP | M | NORMAL |
| | Multimedia Subsystem | | |
| | | | |
+---------------------+--------------------------+-------+----------+
5.49 3GPP TS 26.114 Attribute Analysis
5.50. 3GPP TS 183.063 5.50. 3GPP TS 183.063
[R3GPPTS183.063] Telecommunications and Internet converged Services [TISPAN] describes Telecommunications and Internet converged Services
and Protocols for Advanced Networking (TISPAN); and Protocols for Advanced Networking (TISPAN);
+---------------------+---------------+-------+--------------+ +====================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------------------+---------------+-------+--------------+ +====================+==============+=======+==============+
| PSCid | Not Impacted | S | NORMAL | | PSCid | Not impacted | S | NORMAL |
| | | | | +--------------------+--------------+-------+--------------+
| bc_service | Not Impacted | S | NORMAL | | bc_service | Not impacted | S | NORMAL |
| | | | | +--------------------+--------------+-------+--------------+
| bc_program | Not Impacted | S | NORMAL | | bc_program | Not impacted | S | NORMAL |
| | | | | +--------------------+--------------+-------+--------------+
| bc_service_package | Not Impacted | S | NORMAL | | bc_service_package | Not impacted | S | NORMAL |
| | | | | +--------------------+--------------+-------+--------------+
+---------------------+---------------+-------+--------------+
5.50 3GPP TS 183.063 Attribute Analysis Table 50: 3GPP TS 183.063 Attribute Analysis
5.51. 3GPP TS 24.229 5.51. 3GPP TS 24.229
[R3GPPTS24.229] specifies IP multimedia call control protocol based [IP-CALL] specifies an IP multimedia call control protocol based on
on Session Initial protocol and Session Description Protocol. Session Initial protocol and Session Description Protocol.
+-----------------+-----------------------------+-------+-----------+ +=================+============================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------------+-----------------------------+-------+-----------+ +=================+============================+=======+===========+
| secondary- | secondary-realm MUST be | M | TRANSPORT | | secondary-realm | secondary-realm MUST be | M | TRANSPORT |
| realm | the one that corresponds to | | | | | the one that corresponds | | |
| | the "m=" line chosen for | | | | | to the "m=" line chosen | | |
| | setting up the underlying | | | | | for setting up the | | |
| | transport flow | | | | | underlying transport flow. | | |
| | | | | +-----------------+----------------------------+-------+-----------+
| visited-realm | visited-realm MUST be the | M | TRANSPORT | | visited-realm | visited-realm MUST be the | M | TRANSPORT |
| | one that corresponds to the | | | | | one that corresponds to | | |
| | "m=" line chosen for | | | | | the "m=" line chosen for | | |
| | setting up the underlying | | | | | setting up the underlying | | |
| | transport flow | | | | | transport flow. | | |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-m-cksum | Not Impacted | M | NORMAL | | omr-m-cksum | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-s-cksum | Not Impacted | M | NORMAL | | omr-s-cksum | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-m-att | Not Impacted | M | NORMAL | | omr-m-att | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-s-att | Not Impacted | M | NORMAL | | omr-s-att | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-m-bw | Not Impacted | M | NORMAL | | omr-m-bw | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-s-bw | Not Impacted | M | NORMAL | | omr-s-bw | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
| omr-codecs | Not Impacted | M | NORMAL | | omr-codecs | Not impacted | M | NORMAL |
| | | | | +-----------------+----------------------------+-------+-----------+
+-----------------+-----------------------------+-------+-----------+
5.53 3GPP TS 24.229 Attribute Analysis Table 51: 3GPP TS 24.229 Attribute Analysis
5.52. ITU T.38 5.52. ITU T.38
[T.38] defines procedures for real-time Group 3 facsimile [T.38] defines procedures for real-time Group 3 facsimile
communications over IP networks. communications over IP networks.
+-----------------------+--------------------+-------+--------------+ +=======================+=============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------------------+--------------------+-------+--------------+ +=======================+=============+=======+==============+
| T38FaxVersion | Refer to notes | M | TBD | | T38FaxVersion | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38MaxBitRate | Refer to notes | M | TBD | | T38MaxBitRate | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxFillBitRemoval | Refer to notes | M | TBD | | T38FaxFillBitRemoval | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxTranscodingMMR | Refer to notes | M | TBD | | T38FaxTranscodingMMR | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxTranscodingJBIG | Refer to notes | M | TBD | | T38FaxTranscodingJBIG | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxRateManagement | Refer to notes | M | TBD | | T38FaxRateManagement | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxMaxBuffer | Refer to notes | M | TBD | | T38FaxMaxBuffer | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxMaxDatagram | Refer to notes | M | TBD | | T38FaxMaxDatagram | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxUdpEC | Refer to notes | M | TBD | | T38FaxUdpEC | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxMaxIFP | Refer to notes | M | TBD | | T38FaxMaxIFP | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxUdpECDepth | Refer to notes | M | TBD | | T38FaxUdpECDepth | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38FaxUdpFECMaxSpan | Refer to notes | M | TBD | | T38FaxUdpFECMaxSpan | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38ModemType | Refer to notes | M | TBD | | T38ModemType | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
| T38VendorInfo | Refer to notes | M | TBD | | T38VendorInfo | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +-----------------------+-------------+-------+--------------+
+-----------------------+--------------------+-------+--------------+
5.54 ITU T.38 Attribute Analysis Table 52: ITU T.38 Attribute Analysis
NOTE: As per section 9 of [I-D.ietf-mmusic-sdp-bundle-negotiation], NOTE: As per Section 9 of [RFC8843], there exists no publicly
there exists no publicly available specification that defines available specification that defines procedures for multiplexing/
procedures for multiplexing/demultiplexing fax protocols flows over a demultiplexing fax protocol flows over a single 5-tuple. Once such a
single 5-tuple. Once such a specification is available, the specification is available, the multiplexing category assignments for
multiplexing category assignments for the attributes in this section the attributes in this section could be revisited.
could be revisited.
5.53. ITU-T Q.1970 5.53. ITU-T Q.1970
[Q.1970] defines Bearer Independent Call Control (BICC) IP bearer [Q.1970] defines Bearer Independent Call Control (BICC) IP bearer
control protocol. control protocol.
+-------+----------------------------------------+-------+----------+ +=======+=====================================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-------+----------------------------------------+-------+----------+ +=======+=====================================+=======+==========+
| ipbcp | ipbcp version identifies type of IP | S | SPECIAL | | ipbcp | ipbcp version identifies the types | S | SPECIAL |
| | bearer control protocol (IPBCP) | | | | | of IP bearer control protocol | | |
| | message used in BICC (ITU-T Q.1901) | | | | | (IPBCP) message used in BICC (ITU-T | | |
| | environment which are limited to | | | | | Q.1901) environment that are | | |
| | single media payload. Refer to the | | | | | limited to single-media payload. | | |
| | pertinent ITU-T specifications while | | | | | Refer to the pertinent ITU-T | | |
| | multiplexing | | | | | specifications while multiplexing. | | |
| | | | | +-------+-------------------------------------+-------+----------+
+-------+----------------------------------------+-------+----------+
5.55 ITU-T Q.1970 Attribute Analysis Table 53: ITU-T Q.1970 Attribute Analysis
5.54. ITU-T H.248.15 5.54. ITU-T H.248.15
ITU-T H.248.15 [H.248.15] defines Gateway Control Protocol SDP H.248 ITU-T H.248.15 [H.248.15] defines the Gateway Control Protocol SDP
package attribute H.248 package attribute.
+----------+-------------------------------------+-------+----------+
+==========+=====================================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+----------+-------------------------------------+-------+----------+ +==========+=====================================+=======+==========+
| h248item | It is only applicable for signaling | B | SPECIAL | | h248item | It is only applicable for | B | SPECIAL |
| | the inclusion of H.248 extension | | | | | signaling the inclusion of H.248 | | |
| | packages to a gateway via the local | | | | | extension packages to a gateway | | |
| | and remote descriptors. The | | | | | via the local and remote | | |
| | attribute itself is unaffected by | | | | | descriptors. The attribute | | |
| | multiplexing, but the packaged | | | | | itself is unaffected by | | |
| | referenced in a specific use of the | | | | | multiplexing, but the package | | |
| | attribute can be impacted. Further | | | | | referenced in a specific use of | | |
| | analysis of each package is needed | | | | | the attribute can be impacted. | | |
| | to determine if there is an issue. | | | | | Further analysis of each package | | |
| | This is only a concern in | | | | | is needed to determine if there | | |
| | environments using a decomposed | | | | | is an issue. This is only a | | |
| | server/gateway with H.248 signaled | | | | | concern in environments using a | | |
| | between them. The ITU-T will need | | | | | decomposed server/gateway with | | |
| | to do further analysis of various | | | | | H.248 signaled between them. The | | |
| | packages when they specify how to | | | | | ITU-T will need to do further | | |
| | signal the use of multiplexing to a | | | | | analysis of various packages when | | |
| | gateway | | | | | they specify how to signal the | | |
| | | | | | | use of multiplexing to a gateway. | | |
+----------+-------------------------------------+-------+----------+ +----------+-------------------------------------+-------+----------+
5.56 ITU-T H.248.15 Attribute Analysis Table 54: ITU-T H.248.15 Attribute Analysis
5.55. RFC4975: The Message Session Relay Protocol 5.55. RFC 4975: The Message Session Relay Protocol
[RFC4975] the Message Session Relay Protocol, a protocol for [RFC4975] describes the Message Session Relay Protocol, a protocol
transmitting a series of related instant messages in the context of a for transmitting a series of related instant messages in the context
session. Message sessions are treated like any other media stream of a session. Message sessions are treated like any other media
when set up via a rendezvous or session creation protocol such as the stream when set up via a rendezvous or session-creation protocol such
Session Initiation Protocol. as the Session Initiation Protocol.
+----------------------+---------------------+-------+--------------+ +======================+=============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------------------+---------------------+-------+--------------+ +======================+=============+=======+==============+
| accept-types | Refer to notes | M | TBD | | accept-types | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +----------------------+-------------+-------+--------------+
| accept-wrapped- | Refer to notes | M | TBD | | accept-wrapped-types | Refer to | M | TBD |
| types | below | | | | | notes below | | |
| | | | | +----------------------+-------------+-------+--------------+
| max-size | Refer to notes | M | TBD | | max-size | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +----------------------+-------------+-------+--------------+
| path | Refer to notes | M | TBD | | path | Refer to | M | TBD |
| | below | | | | | notes below | | |
| | | | | +----------------------+-------------+-------+--------------+
+----------------------+---------------------+-------+--------------+
5.57 RFC4975 Attribute Analysis Table 55: RFC 4975 Attribute Analysis
NOTE: As per section 9 of [I-D.ietf-mmusic-sdp-bundle-negotiation], NOTE: As per Section 9 of [RFC8843], there exists no publicly
there exists no publicly available specification that defines available specification that defines procedures for multiplexing/
procedures for multiplexing/demultiplexing MRSP flows over a single demultiplexing MSRP flows over a single 5-tuple. Once such a
5-tuple. Once such a specification is available, the multiplexing specification is available, the multiplexing categories assignments
categories assignments for the attributes in this section could be for the attributes in this section could be revisited.
revisited.
5.56. Historical Attributes 5.56. Historical Attributes
This section specifies analysis for the attributes that are included This section specifies analysis for the attributes that are included
for historic usage alone by the [IANA]. for historic usage alone by the [IANA].
+----------+----------------------+-------+--------------+ +=========+=====================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+----------+----------------------+-------+--------------+ +=========+=====================+=======+==============+
| rtpred1 | Historic attributes | M | CAUTION | | rtpred1 | Historic attributes | M | CAUTION |
| | | | | +---------+---------------------+-------+--------------+
| rtpred2 | Historic attributes | M | CAUTION | | rtpred2 | Historic attributes | M | CAUTION |
| | | | | +---------+---------------------+-------+--------------+
+----------+----------------------+-------+--------------+
5.58 Historical Attribute Analysis Table 56: Historical Attribute Analysis
6. bwtype Attribute Analysis 6. bwtype Attribute Analysis
This section specifies handling of specific bandwidth attributes when This section specifies handling of specific bandwidth attributes when
used in multiplexing scenarios. used in multiplexing scenarios.
6.1. RFC4566: SDP 6.1. RFC 4566: SDP
[RFC4566] defines SDP that is intended for describing multimedia [RFC4566] defines SDP that is intended for describing multimedia
sessions for the purposes of session announcement, session sessions for the purposes of session announcement, session
invitation, and other forms of multimedia session initiation. invitation, and other forms of multimedia session initiation.
+-----------+------------------------------------+-------+----------+ +===========+=================================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------+------------------------------------+-------+----------+ +===========+=================================+=======+==========+
| bwtype:CT | Not Impacted | S | NORMAL | | bwtype:CT | Not impacted | S | NORMAL |
| | | | | +-----------+---------------------------------+-------+----------+
| bwtype:AS | For the media level usage, the | B | SUM | | bwtype:AS | For media-level usage, the | B | SUM |
| | aggregate of individual bandwidth | | | | | aggregate of individual | | |
| | values is considered | | | | | bandwidth values is considered. | | |
| | | | | +-----------+---------------------------------+-------+----------+
+-----------+------------------------------------+-------+----------+
6.1 RFC4566 bwtype Analysis Table 57: RFC 4566 bwtype Analysis
6.2. RFC3556: SDP Bandwidth Modifiers for RTCP Bandwidth 6.2. RFC 3556: SDP Bandwidth Modifiers for RTCP Bandwidth
[RFC3556] defines an extension to SDP to specify two additional [RFC3556] defines an extension to SDP to specify two additional
modifiers for the bandwidth attribute. These modifiers may be used modifiers for the bandwidth attribute. These modifiers may be used
to specify the bandwidth allowed for RTCP packets in a RTP session. to specify the bandwidth allowed for RTCP packets in an RTP session.
+-----------+------------------------------------+-------+----------+ +===========+================================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------+------------------------------------+-------+----------+ +===========+================================+=======+==========+
| bwtype:RS | Session level usage represents | B | SUM | | bwtype:RS | Session-level usage represents | B | SUM |
| | session aggregate and media level | | | | | session aggregate, and media- | | |
| | usage indicates SUM of the | | | | | level usage indicates SUM of | | |
| | individual values while | | | | | the individual values while | | |
| | multiplexing | | | | | multiplexing. | | |
| | | | | +-----------+--------------------------------+-------+----------+
| bwtype:RR | Session level usage represents | B | SUM | | bwtype:RR | Session-level usage represents | B | SUM |
| | session aggregate and media level | | | | | session aggregate, and media- | | |
| | usage indicates SUM of the | | | | | level usage indicates SUM of | | |
| | individual values while | | | | | the individual values while | | |
| | multiplexing | | | | | multiplexing. | | |
| | | | | +-----------+--------------------------------+-------+----------+
+-----------+------------------------------------+-------+----------+
6.2 RFC3556 bwtype Analysis Table 58: RFC 3556 bwtype Analysis
6.3. RFC3890: Bandwidth Modifier for SDP 6.3. RFC 3890: Bandwidth Modifier for SDP
[RFC3890] defines SDP Transport Independent Application Specific [RFC3890] defines SDP Transport Independent Application Specific
Maximum (TIAS) bandwidth modifier that does not include transport Maximum (TIAS) bandwidth modifier that does not include transport
overhead; instead an additional packet rate attribute is defined. overhead; instead, an additional packet-rate attribute is defined.
The transport independent bit-rate value together with the maximum The transport-independent bitrate value together with the maximum
packet rate can then be used to calculate the real bit-rate over the packet rate can then be used to calculate the real bitrate over the
transport actually used. transport actually used.
+-------------+----------------------------------+-------+----------+ +=============+==================================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+=============+==================================+=======+==========+
| bwtype:TIAS | The usage of TIAS is not | B | SPECIAL |
| | defined under offer/answer | | |
| | usage. | | |
+-------------+----------------------------------+-------+----------+ +-------------+----------------------------------+-------+----------+
| bwtype:TIAS | The usage of TIAS is not defined | B | SPECIAL | | maxprate | The usage of TIAS and | B | SPECIAL |
| | under Offer/Answer usage. | | | | | maxprate is not well | | |
| | | | | | | defined under multiplexing. | | |
| maxprate | The usage of TIAS and maxprate | B | SPECIAL |
| | is not well defined under | | |
| | multiplexing | | |
| | | | |
+-------------+----------------------------------+-------+----------+ +-------------+----------------------------------+-------+----------+
6.3 RFC3890 bwtype Analysis Table 59: RFC 3890 bwtype Analysis
NOTE: The intention of TIAS is that the media level bit-rate is NOTE: The intention of TIAS is that the media-level bitrate is
multiplied with the known per-packet overhead for the selected multiplied with the known per-packet overhead for the selected
transport and the maxprate value to determine the worst case bit-rate transport and the maxprate value to determine the worst-case bitrate
from the transport to more accurately capture the required usage. from the transport to more accurately capture the required usage.
Summing TIAS values independently across "m=" lines and multiplying Summing TIAS values independently across "m=" lines and multiplying
the computed sum with maxprate and the per-packet overhead would the computed sum with maxprate and the per-packet overhead would
inflate the value significantly. Instead performing multiplication inflate the value significantly. Instead, performing multiplication
and adding the individual values is a more appropriate usage. and adding the individual values is a more appropriate usage.
7. rtcp-fb Attribute Analysis 7. rtcp-fb Attribute Analysis
This section analyzes rtcp-fb SDP attributes. This section analyzes rtcp-fb SDP attributes.
7.1. RFC4585: RTP/AVPF 7.1. RFC 4585: RTP/AVPF
[RFC4585] defines an extension to the Audio-visual Profile (AVP) that [RFC4585] defines an extension to the Audio-Visual Profile (AVP) that
enables receivers to provide, statistically, more immediate feedback enables receivers to provide, statistically, more immediate feedback
to the senders and thus allows for short-term adaptation and to the senders; it thus allows for short-term adaptation and
efficient feedback-based repair mechanisms to be implemented. implementation of efficient feedback-based repair mechanisms.
+---------+------------------------------+-------+------------------+ +=========+=============================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+------------------------------+-------+------------------+ +=========+=============================+=======+==================+
| ack | The attribute value MUST be | M | IDENTICAL-PER- | | ack | The attribute value MUST be | M | IDENTICAL-PER-PT |
| rpsi | same for a given codec | | PT | | rpsi | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| ack | Feedback parameters MUST be | M | SPECIAL | | ack app | Feedback parameters MUST be | M | SPECIAL |
| app | handled in the app specific | | | | | handled in the app-specific | | |
| | way when multiplexed | | | | | way when multiplexed. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST be | M | IDENTICAL-PER-PT |
| | same for a given codec | | PT | | | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST be | M | IDENTICAL-PER-PT |
| pli | same for a given codec | | PT | | pli | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST be | M | IDENTICAL-PER-PT |
| sli | same for a given codec | | PT | | sli | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST be | M | IDENTICAL-PER-PT |
| rpsi | same for a given codec | | PT | | rpsi | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| nack | Feedback parameters MUST be | M | SPECIAL | | nack | Feedback parameters MUST be | M | SPECIAL |
| app | handled in the app specific | | | | app | handled in the app specific | | |
| | way when multiplexed | | | | | way when multiplexed. | | |
| | | | | +---------+-----------------------------+-------+------------------+
| trr- | The attribute value MUST be | M | IDENTICAL-PER- | | trr-int | The attribute value MUST be | M | IDENTICAL-PER-PT |
| int | same for a given codec | | PT | | | the same for a given codec | | |
| | configuration | | | | | configuration. | | |
| | | | | +---------+-----------------------------+-------+------------------+
+---------+------------------------------+-------+------------------+
7.1 RFC4585 Attribute Analysis Table 60: RFC 4585 Attribute Analysis
7.2. RFC5104: Codec Control Messages in AVPF 7.2. RFC 5104: Codec Control Messages in AVPF
[RFC5104] specifies a few extensions to the messages defined in the [RFC5104] specifies a few extensions to the messages defined in the
Audio-Visual Profile with Feedback (AVPF). They are helpful Audio-Visual Profile with Feedback (AVPF). They are helpful
primarily in conversational multimedia scenarios where centralized primarily in conversational multimedia scenarios where centralized
multipoint functionalities are in use. However, some are also usable multipoint functionalities are in use. However, some are also usable
in smaller multicast environments and point-to-point calls. in smaller multicast environments and point-to-point calls.
+------+---------------------------------+-------+------------------+ +======+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------+---------------------------------+-------+------------------+ +======+==========================+=======+==================+
| ccm | The attribute value MUST be | M | IDENTICAL-PER- | | ccm | The attribute value MUST | M | IDENTICAL-PER-PT |
| | same for a given codec | | PT | | | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +------+--------------------------+-------+------------------+
+------+---------------------------------+-------+------------------+
7.2 RFC5104 Attribute Analysis Table 61: RFC 5104 Attribute Analysis
7.3. RFC6285: Unicast-Based Rapid Acquisition of Multicast RTP Sessions 7.3. RFC 6285: Unicast-Based Rapid Acquisition of Multicast RTP
(RAMS) Sessions (RAMS)
[RFC6285] describes a method using the existing RTP and RTCP [RFC6285] describes a method of using the existing RTP and RTCP
machinery that reduces the acquisition delay. In this method, an machinery that reduces the acquisition delay. In this method, an
auxiliary unicast RTP session carrying the Reference Information to auxiliary unicast RTP session carrying the Reference Information to
the receiver precedes or accompanies the multicast stream. This the receiver precedes or accompanies the multicast stream. This
unicast RTP flow can be transmitted at a faster than natural bitrate unicast RTP flow can be transmitted at a faster-than-natural bitrate
to further accelerate the acquisition. The motivating use case for to further accelerate the acquisition. The motivating use case for
this capability is multicast applications that carry real-time this capability is multicast applications that carry real-time
compressed audio and video. compressed audio and video.
+--------+-------------------------------+-------+------------------+ +======+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------+-------------------------------+-------+------------------+ +======+==========================+=======+==================+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST | M | IDENTICAL-PER-PT |
| rai | same for a given codec | | PT | | rai | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +------+--------------------------+-------+------------------+
+--------+-------------------------------+-------+------------------+
7.3 RFC6285 Attribute Analysis Table 62: RFC 6285 Attribute Analysis
7.4. RFC6679: ECN for RTP over UDP/IP 7.4. RFC 6679: ECN for RTP over UDP/IP
[RFC6679] specifies how Explicit Congestion Notification (ECN) can be [RFC6679] specifies how Explicit Congestion Notification (ECN) can be
used with the RTP running over UDP, using the RTCP as a feedback used with the RTP running over UDP, using the RTCP as a feedback
mechanism. It defines a new RTCP Extended Report (XR) block for mechanism. It defines a new RTCP Extended Report (XR) block for
periodic ECN feedback, a new RTCP transport feedback message for periodic ECN feedback, a new RTCP transport feedback message for
timely reporting of congestion events, and a STUN extension used in timely reporting of congestion events, and a STUN extension used in
the optional initialization method using ICE. the optional initialization method using ICE.
+-----------------+-----------------------------+-------+-----------+ +=================+============================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+-----------------+-----------------------------+-------+-----------+ +=================+============================+=======+===========+
| ecn-capable- | ECN markup are enabled at | M | IDENTICAL | | ecn-capable-rtp | ECN markup is enabled at | M | IDENTICAL |
| rtp | the RTP session level | | | | | the RTP session level. | | |
| | | | | +-----------------+----------------------------+-------+-----------+
| nack ecn | This attribute enables ECN | M | IDENTICAL | | nack ecn | This attribute enables ECN | M | IDENTICAL |
| | at the RTP session level | | | | | at the RTP session level. | | |
| | | | | +-----------------+----------------------------+-------+-----------+
+-----------------+-----------------------------+-------+-----------+
7.4 RFC6679 Attribute Analysis Table 63: RFC 6679 Attribute Analysis
7.5. RFC6642: Third-Party Loss Report 7.5. RFC 6642: Third-Party Loss Report
In a large RTP session using the RTCP feedback mechanism defined in In a large RTP session using the RTCP feedback mechanism defined in
[RFC4585], a feedback target may experience transient overload if [RFC4585], a feedback target may experience transient overload if
some event causes a large number of receivers to send feedback at some event causes a large number of receivers to send feedback at
once. This overload is usually avoided by ensuring that feedback once. This overload is usually avoided by ensuring that feedback
reports are forwarded to all receivers, allowing them to avoid reports are forwarded to all receivers, allowing them to avoid
sending duplicate feedback reports. However, there are cases where sending duplicate feedback reports. However, there are cases where
it is not recommended to forward feedback reports, and this may allow it is not recommended to forward feedback reports, and this may allow
feedback implosion. [RFC6642] memo discusses these cases and defines feedback implosion. [RFC6642] discusses these cases and defines a
a new RTCP Third-Party Loss Report that can be used to inform new RTCP Third-Party Loss Report that can be used to inform receivers
receivers that the feedback target is aware of some loss event, that the feedback target is aware of some loss event, allowing them
allowing them to suppress feedback. Associated SDP signaling is also to suppress feedback. Associated SDP signaling is also defined.
defined.
+---------+------------------------------+-------+------------------+ +=======+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------+------------------------------+-------+------------------+ +=======+==========================+=======+==================+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST | M | IDENTICAL-PER-PT |
| tllei | same for a given codec | | PT | | tllei | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
| nack | The attribute value MUST be | M | IDENTICAL-PER- | | nack | The attribute value MUST | M | IDENTICAL-PER-PT |
| pslei | same for a given codec | | PT | | pslei | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
+---------+------------------------------+-------+------------------+
7.5 RFC6642 Attribute Analysis Table 64: RFC 6642 Attribute Analysis
7.6. RFC5104: Codec Control Messages in AVPF 7.6. RFC 5104: Codec Control Messages in AVPF
[RFC5104] specifies a few extensions to the messages defined in the [RFC5104] specifies a few extensions to the messages defined in the
Audio-Visual Profile with Feedback (AVPF). They are helpful Audio-Visual Profile with Feedback (AVPF). They are helpful
primarily in conversational multimedia scenarios where centralized primarily in conversational multimedia scenarios where centralized
multipoint functionalities are in use. However, some are also usable multipoint functionalities are in use. However, some are also usable
in smaller multicast environments and point-to-point calls. in smaller multicast environments and point-to-point calls.
+--------+-------------------------------+-------+------------------+ +=======+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------+-------------------------------+-------+------------------+ +=======+==========================+=======+==================+
| ccm | The attribute value MUST be | M | IDENTICAL-PER- | | ccm | The attribute value MUST | M | IDENTICAL-PER-PT |
| fir | same for a given codec | | PT | | fir | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
| ccm | The attribute value MUST be | M | IDENTICAL-PER- | | ccm | The attribute value MUST | M | IDENTICAL-PER-PT |
| tmmbr | same for a given codec | | PT | | tmmbr | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
| ccm | The attribute value MUST be | M | IDENTICAL-PER- | | ccm | The attribute value MUST | M | IDENTICAL-PER-PT |
| tstr | same for a given codec | | PT | | tstr | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
| ccm | The attribute value MUST be | M | IDENTICAL-PER- | | ccm | The attribute value MUST | M | IDENTICAL-PER-PT |
| vbcm | same for a given codec | | PT | | vbcm | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-------+--------------------------+-------+------------------+
+--------+-------------------------------+-------+------------------+
7.6 RFC5104 Attribute Analysis Table 65: RFC 5104 Attribute Analysis
8. group Attribute Analysis 8. group Attribute Analysis
This section analyzes SDP "group" attribute semantics [RFC5888]. This section analyzes SDP "group" attribute semantics [RFC5888].
8.1. RFC5888: SDP Grouping Framework 8.1. RFC 5888: SDP Grouping Framework
[RFC5888] defines a framework to group "m" lines in SDP for different [RFC5888] defines a framework to group "m=" lines in SDP for
purposes. different purposes.
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| group:LS | Not Impacted | S | NORMAL | | group:LS | Not impacted | S | NORMAL |
| | | | | +-----------+--------------+-------+--------------+
| group:FID | Not Impacted | S | NORMAL | | group:FID | Not impacted | S | NORMAL |
| | | | | +-----------+--------------+-------+--------------+
+------------+---------------+-------+--------------+
8.1 RFC5888 Attribute Analysis Table 66: RFC 5888 Attribute Analysis
8.2. RFC3524: Mapping Media Streams to Resource Reservation Flows 8.2. RFC 3524: Mapping Media Streams to Resource Reservation Flows
[RFC3524] defines an extension to the SDP grouping framework. It [RFC3524] defines an extension to the SDP grouping framework. It
allows requesting a group of media streams to be mapped into a single allows requesting a group of media streams to be mapped into a single
resource reservation flow. The SDP syntax needed is defined, as well resource reservation flow. The SDP syntax needed is defined, as well
as a new "semantics" attribute called Single Reservation Flow (SRF). as a new "semantics" attribute called Single Reservation Flow (SRF).
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| group:SRF | Not Impacted | S | NORMAL | | group:SRF | Not impacted | S | NORMAL |
| | | | | +-----------+--------------+-------+--------------+
+------------+---------------+-------+--------------+
8.2 RFC3524 Attribute Analysis Table 67: RFC 3524 Attribute Analysis
8.3. RFC4091: ANAT Semantics 8.3. RFC 4091: ANAT Semantics
[RFC4091] defines ANAT semantics for the SDP grouping framework. The [RFC4091] defines ANAT semantics for the SDP grouping framework.
ANAT semantics allow alternative types of network addresses to (Note: [RFC4091] has been obsoleted by [RFC8445].) The ANAT
establish a particular media stream. semantics allow alternative types of network addresses to establish a
particular media stream.
+-------------+------------------------------+-------+--------------+ +============+==============================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------------+------------------------------+-------+--------------+ +============+==============================+=======+==============+
| group:ANAT | ANAT semantics is obsoleted | S | CAUTION | | group:ANAT | ANAT semantics is obsoleted. | S | CAUTION |
| | | | | +------------+------------------------------+-------+--------------+
+-------------+------------------------------+-------+--------------+
8.3 RFC4091 Attribute Analysis Table 68: RFC 4091 Attribute Analysis
8.4. RFC5956: FEC Grouping Semantics in SDP 8.4. RFC 5956: FEC Grouping Semantics in SDP
[RFC5956] defines the semantics for grouping the associated source [RFC5956] defines the semantics for grouping the associated source
and FEC-based (Forward Error Correction) repair flows in SDP. The and FEC-based repair flows in SDP. The semantics defined in the
semantics defined in the document are to be used with the SDP document are to be used with the SDP Grouping Framework [RFC5888].
Grouping Framework [RFC5888]. These semantics allow the description These semantics allow the description of grouping relationships
of grouping relationships between the source and repair flows when between the source and repair flows when one or more source and/or
one or more source and/or repair flows are associated in the same repair flows are associated in the same group; they also provide
group, and they provide support for additive repair flows. SSRC- support for additive repair flows. SSRC-level grouping semantics are
level (Synchronization Source) grouping semantics are also defined in also defined in this document for RTP streams using SSRC
this document for RTP streams using SSRC multiplexing. multiplexing.
+---------------+---------------+-------+--------------+ +==============+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+---------------+---------------+-------+--------------+ +==============+==============+=======+==============+
| group:FEC-FR | Not Impacted | S | NORMAL | | group:FEC-FR | Not impacted | S | NORMAL |
| | | | | +--------------+--------------+-------+--------------+
+---------------+---------------+-------+--------------+
8.4 RFC5956 Attribute Analysis Table 69: RFC 5956 Attribute Analysis
8.5. RFC5583: Signaling Media Decoding Dependency in SDP 8.5. RFC 5583: Signaling Media Decoding Dependency in SDP
[RFC5583] defines semantics that allow for signaling the decoding [RFC5583] defines semantics that allow for signaling the decoding
dependency of different media descriptions with the same media type dependency of different media descriptions with the same media type
in SDP. This is required, for example, if media data is separated in SDP. This is required, for example, if media data is separated
and transported in different network streams as a result of the use and transported in different network streams as a result of using a
of a layered or multiple descriptive media coding process. layered or multiple descriptive media coding process.
+-----------+----------------------------+-------+------------------+ +===========+==========================+=======+==================+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------+----------------------------+-------+------------------+ +===========+==========================+=======+==================+
| group:DDP | Not Impacted | S | NORMAL | | group:DDP | Not impacted | S | NORMAL |
| | | | | +-----------+--------------------------+-------+------------------+
| depend | The attribute value MUST | M | IDENTICAL-PER- | | depend | The attribute value MUST | M | IDENTICAL-PER-PT |
| lay | be same for a given codec | | PT | | lay | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-----------+--------------------------+-------+------------------+
| depend | The attribute value MUST | M | IDENTICAL-PER- | | depend | The attribute value MUST | M | IDENTICAL-PER-PT |
| mdc | be same for a given codec | | PT | | mdc | be the same for a given | | |
| | configuration | | | | | codec configuration. | | |
| | | | | +-----------+--------------------------+-------+------------------+
+-----------+----------------------------+-------+------------------+
8.5 RFC5583 Attribute Analysis Table 70: RFC 5583 Attribute Analysis
8.6. RFC7104: Duplication Grouping Semantics in the SDP 8.6. RFC 7104: Duplication Grouping Semantics in the SDP
[RFC7104] defines the semantics for grouping redundant streams in [RFC7104] defines the semantics for grouping redundant streams in
SDP, The semantics defined in this document are to be used with the SDP. The semantics defined in this document are to be used with the
SDP Grouping Framework. Grouping semantics at the SSRC)level are SDP Grouping Framework. Grouping semantics at the synchronization
also defined in this document for RTP streams using SSRC source (SSRC) level are also defined in this document for RTP streams
multiplexing. using SSRC multiplexing.
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------+---------------+-------+--------------+ +===========+==============+=======+==============+
| group:DUP | Not Impacted | S | NORMAL | | group:DUP | Not impacted | S | NORMAL |
| | | | | +-----------+--------------+-------+--------------+
+------------+---------------+-------+--------------+
8.6 RFC7104 Attribute Analysis Table 71: RFC 7104 Attribute Analysis
9. ssrc-group Attribute Analysis 9. ssrc-group Attribute Analysis
This section analyzes "ssrc-group" semantics. This section analyzes "ssrc-group" semantics.
9.1. RFC5576: Source-Specific SDP Attributes 9.1. RFC 5576: Source-Specific SDP Attributes
[RFC5576] defines a mechanism to describe RTP media sources, which [RFC5576] defines a mechanism for describing RTP media sources --
are identified by their synchronization source (SSRC) identifiers, in which are identified by their synchronization source (SSRC)
SDP, to associate attributes with these sources, and to express identifiers -- in SDP, to associate attributes with these sources and
relationships among sources. It also defines several source-level express relationships among sources. It also defines several source-
attributes that can be used to describe properties of media sources. level attributes that can be used to describe properties of media
sources.
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+--------------------+---------------+-------+--------------+ +===================+==============+=======+==============+
| ssrc-group:FID | Not Impacted | SR | NORMAL | | ssrc-group:FID | Not impacted | SR | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ssrc-group:FEC | Not Impacted | SR | NORMAL | | ssrc-group:FEC | Not impacted | SR | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
| ssrc-group:FEC-FR | Not Impacted | SR | NORMAL | | ssrc-group:FEC-FR | Not impacted | SR | NORMAL |
| | | | | +-------------------+--------------+-------+--------------+
+--------------------+---------------+-------+--------------+
9.1 RFC5576 Attribute Analysis Table 72: RFC 5576 Attribute Analysis
9.2. RFC7104: Duplication Grouping Semantics in the SDP 9.2. RFC 7104: Duplication Grouping Semantics in the SDP
[RFC7104] defines the semantics for grouping redundant streams in [RFC7104] defines the semantics for grouping redundant streams in
SDP. The semantics defined in this document are to be used with the SDP. The semantics defined in this document are to be used with the
SDP Grouping Framework. Grouping semantics at the Synchronization SDP Grouping Framework. Grouping semantics at the synchronization
Source (SSRC) level are also defined in this document for RTP streams source (SSRC) level are also defined in this document for RTP streams
using SSRC multiplexing. using SSRC multiplexing.
+-----------------+---------------+-------+--------------+ +================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-----------------+---------------+-------+--------------+ +================+==============+=======+==============+
| ssrc-group:DUP | Not Impacted | SR | NORMAL | | ssrc-group:DUP | Not impacted | SR | NORMAL |
| | | | | +----------------+--------------+-------+--------------+
+-----------------+---------------+-------+--------------+
9.2 RFC7104 Attribute Analysis Table 73: RFC 7104 Attribute Analysis
10. QoS Mechanism Token Analysis 10. QoS Mechanism Token Analysis
This section analyzes QoS tokes specified with SDP. This section analyzes QoS tokes specified with SDP.
10.1. RFC5432: QoS Mechanism Selection in SDP 10.1. RFC 5432: QoS Mechanism Selection in SDP
[RFC5432] defines procedures to negotiate QOS mechanisms using the [RFC5432] defines procedures to negotiate QoS mechanisms using the
SDP offer/answer model. SDP offer/answer model.
+------+----------------------------------------+-------+-----------+ +======+================================+=======+===========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+------+----------------------------------------+-------+-----------+ +======+================================+=======+===========+
| rsvp | rsvp attribute MUST be the one that | B | TRANSPORT | | rsvp | rsvp attribute MUST be the one | B | TRANSPORT |
| | corresponds to the "m=" line chosen | | | | | that corresponds to the "m=" | | |
| | for setting up the underlying | | | | | line chosen for setting up the | | |
| | transport flow | | | | | underlying transport flow. | | |
| | | | | +------+--------------------------------+-------+-----------+
| nsis | rsvp attribute MUST be the one that | B | TRANSPORT | | nsis | rsvp attribute MUST be the one | B | TRANSPORT |
| | corresponds to the "m=" line chosen | | | | | that corresponds to the "m=" | | |
| | for setting up the underlying | | | | | line chosen for setting up the | | |
| | transport | | | | | underlying transport. | | |
| | | | | +------+--------------------------------+-------+-----------+
+------+----------------------------------------+-------+-----------+
10.1 RFC5432 Attribute Analysis Table 74: RFC 5432 Attribute Analysis
NOTE: A single Differentiated Services Code Point (DSCP) code point NOTE: A single Differentiated Services Code Point (DSCP) for each
per flow being multiplexed doesn't impact multiplexing since QOS flow being multiplexed doesn't impact multiplexing, since QoS
mechanisms are signaled/scoped per flow. For scenarios that involve mechanisms are signaled/scoped per flow. For scenarios that involve
having different DSCP code points for packets being transmitted over having different DSCP code points for packets being transmitted over
the same 5-tuple, issues as discussed in [RFC7657] need to be taken the same 5-tuple, issues as discussed in [RFC7657] need to be taken
into consideration. into consideration.
11. k= Attribute Analysis 11. k= Attribute Analysis
11.1. RFC4566: SDP
11.1. RFC 4566: SDP
[RFC4566] defines SDP that is intended for describing multimedia [RFC4566] defines SDP that is intended for describing multimedia
sessions for the purposes of session announcement, session sessions for the purposes of session announcement, session
invitation, and other forms of multimedia session initiation. invitation, and other forms of multimedia session initiation.
+------+-----------------------------------------+-------+----------+ +======+===================================+=======+==============+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux Category |
| | | | Category | +======+===================================+=======+==============+
+------+-----------------------------------------+-------+----------+ | k= | It is not recommended to use this | S | CAUTION |
| k= | It is not recommended to use this | S | CAUTION | | | attribute under multiplexing. | | |
| | attribute under multiplexing | | | +------+-----------------------------------+-------+--------------+
| | | | |
+------+-----------------------------------------+-------+----------+
11.1 RFC4566 Attribute Analysis Table 75: RFC 4566 Attribute Analysis
12. content Attribute Analysis 12. content Attribute Analysis
12.1. RFC4796 12.1. RFC 4796
[RFC4796] defines a new SDP media-level attribute, 'content'. The [RFC4796] defines a new SDP media-level attribute, "content". The
'content' attribute defines the content of the media stream to a more "content" attribute defines the content of the media stream to a more
detailed level than the media description line. The sender of an SDP detailed level than the media description line. The sender of an SDP
session description can attach the 'content' attribute to one or more session description can attach the "content" attribute to one or more
media streams. The receiving application can then treat each media media streams. The receiving application can then treat each media
stream differently (e.g., show it on a big or small screen) based on stream differently (e.g., show it on a big or small screen) based on
its content. its content.
+------------------+---------------+-------+--------------+ +=================+==============+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+------------------+---------------+-------+--------------+ +=================+==============+=======+==============+
| content:slides | Not Impacted | M | NORMAL | | content:slides | Not impacted | M | NORMAL |
| | | | | +-----------------+--------------+-------+--------------+
| content:speaker | Not Impacted | M | NORMAL | | content:speaker | Not impacted | M | NORMAL |
| | | | | +-----------------+--------------+-------+--------------+
| content:main | Not Impacted | M | NORMAL | | content:main | Not impacted | M | NORMAL |
| | | | | +-----------------+--------------+-------+--------------+
| content:sl | Not Impacted | M | NORMAL | | content:sl | Not impacted | M | NORMAL |
| | | | | +-----------------+--------------+-------+--------------+
| content:alt | Not Impacted | M | NORMAL | | content:alt | Not impacted | M | NORMAL |
| | | | | +-----------------+--------------+-------+--------------+
+------------------+---------------+-------+--------------+
12.1 RFC4796 Attribute Analysis Table 76: RFC 4796 Attribute Analysis
12.2. 3GPP TS 24.182 12.2. 3GPP TS 24.182
[R3GPPTS24.182] specifies IP multimedia subsystem Custom Alerting [IMS-CAT] specifies an IP multimedia subsystem for customized
tones alerting tones.
+-------------+---------------+-------+--------------+ +============+=========================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------------+---------------+-------+--------------+ +============+=========================+=======+==============+
| g.3gpp.cat | Not Impacted | M | NORMAL | | g.3gpp.cat | Usage defined for the | M | NORMAL |
| | | | | | | IP multimedia subsystem | | |
+-------------+---------------+-------+--------------+ +------------+-------------------------+-------+--------------+
12.2 3GPP TS 24.182 Attribute Analysis Table 77: 3GPP TS 24.182 Attribute Analysis
12.3. 3GPP TS 24.183 12.3. 3GPP TS 24.183
[R3GPPTS24.183] specifies IP multimedia subsystem Custom Ringing [IMS-CRS] specifies an IP multimedia subsystem for customized ringing
Signal signal.
+-------------+---------------+-------+--------------+ +============+=========================+=======+==============+
| Name | Notes | Level | Mux Category | | Name | Notes | Level | Mux Category |
+-------------+---------------+-------+--------------+ +============+=========================+=======+==============+
| g.3gpp.crs | Not Impacted | M | NORMAL | | g.3gpp.crs | Usage defined for the | M | NORMAL |
| | | | | | | IP multimedia subsystem | | |
+-------------+---------------+-------+--------------+ +------------+-------------------------+-------+--------------+
12.3 3GPP TS 24.183 Attribute Analysis Table 78: 3GPP TS 24.183 Attribute Analysis
13. Payload Formats 13. Payload Formats
13.1. RFC5109: RTP Payload Format for Generic FEC 13.1. RFC 5109: RTP Payload Format for Generic FEC
[RFC5109] describes a payload format for generic Forward Error [RFC5109] describes a payload format for generic Forward Error
Correction (FEC) for media data encapsulated in RTP. It is based on Correction (FEC) for media data encapsulated in RTP. It is based on
the exclusive-or (parity) operation. The payload format allows end the exclusive-or (parity) operation. The payload format allows end
systems to apply protection using various protection lengths and systems to apply protection using various protection lengths and
levels, in addition to using various protection group sizes to adapt levels, in addition to using various protection group sizes to adapt
to different media and channel characteristics. It enables complete to different media and channel characteristics. It enables complete
recovery of the protected packets or partial recovery of the critical recovery of the protected packets or partial recovery of the critical
parts of the payload depending on the packet loss situation. parts of the payload, depending on the packet loss situation.
+--------------------+---------------------------+-------+----------+ +==============+=====================+=======+==========+
| Name | Notes | Level | Mux | | Name | Notes | Level | Mux |
| | | | Category | | | | | Category |
+--------------------+---------------------------+-------+----------+ +==============+=====================+=======+==========+
| audio/ulpfec | Not recommended for | M | CAUTION | | audio/ulpfec | Not recommended for | M | CAUTION |
| | multiplexing due to reuse | | | | | multiplexing due to | | |
| | of SSRCs | | | | | reuse of SSRCs. | | |
| | | | | +--------------+---------------------+-------+----------+
| video/ulpfec | Not recommended for | M | CAUTION | | video/ulpfec | Not recommended for | M | CAUTION |
| | multiplexing due to reuse | | | | | multiplexing due to | | |
| | of SSRCs | | | | | reuse of SSRCs. | | |
| | | | | +--------------+---------------------+-------+----------+
| text/ulpfec | Not recommended for | M | CAUTION | | text/ulpfec | Not recommended for | M | CAUTION |
| | multiplexing due to reuse | | | | | multiplexing due to | | |
| | of SSRCs | | | | | reuse of SSRCs. | | |
| | | | | +--------------+---------------------+-------+----------+
| application/ulpfec | Not recommended for | M | CAUTION | | application/ | Not recommended for | M | CAUTION |
| | multiplexing due to reuse | | | | ulpfec | multiplexing due to | | |
| | of SSRCs | | | | | reuse of SSRCs. | | |
| | | | | +--------------+---------------------+-------+----------+
+--------------------+---------------------------+-------+----------+
13.1 RFC5109 Payload Format Analysis Table 79: RFC 5109 Payload Format Analysis
14. Multiplexing Considerations for Encapsulating Attributes 14. Multiplexing Considerations for Encapsulating Attributes
This sections deals with recommendations for defining the This section deals with recommendations for defining the multiplexing
multiplexing characteristics of the SDP attributes that encapsulate characteristics of the SDP attributes that encapsulate other SDP
other SDP attributes/parameters. Such attributes as of today, for attributes/parameters. As of today, such attributes, for example,
example, are defined in [RFC3407], [RFC5939] and [RFC6871] as part of are defined in [RFC3407], [RFC5939] and [RFC6871] as part of a
a generic framework for indicating and negotiating transport, media, generic framework for indicating and negotiating transport-, media-,
and media format related capabilities in the SDP. and media-format-related capabilities in the SDP.
The behavior of such attributes under multiplexing is in turn defined The behavior of such attributes under multiplexing is, in turn,
by the multiplexing behavior of the attributes they encapsulate which defined by the multiplexing behavior of the attributes they
are made known once the Offer/Answer negotiation process is encapsulate, which are made known once the offer/answer negotiation
completed. process is completed.
14.1. RFC3407: cpar Attribute Analysis 14.1. RFC 3407: cpar Attribute Analysis
[RFC3407] capability parameter attribute (a=cpar) encapsulates b= The [RFC3407] capability parameter attribute "a=cpar" encapsulates a
(bandwidth) or an a= attribute. For bandwidth attribute "b=" (bandwidth) or an "a=" attribute. For bandwidth attribute
encapsulation, the category SUM is inherited. For the case of a= encapsulation, the category SUM is inherited. For the case of "a="
attribute, the category corresponding to the SDP attribute being attribute, the category corresponding to the SDP attribute being
encapsulated is inherited. encapsulated is inherited.
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
m=video 3456 RTP/AVP 100 m=video 3456 RTP/AVP 100
a=rtpmap:100 VP8/90000 a=rtpmap:100 VP8/90000
a=sqn: 0 a=sqn: 0
a=cdsc: 1 video RTP/AVP 100 a=cdsc: 1 video RTP/AVP 100
a=cpar: a=rtcp-mux a=cpar: a=rtcp-mux
m=video 3456 RTP/AVP 101 m=video 3456 RTP/AVP 101
a=rtpmap:101 VP8/90000 a=rtpmap:101 VP8/90000
a=fmtp:100 max-fr=15;max-fs=1200 a=fmtp:100 max-fr=15;max-fs=1200
a=cdsc: 2 video RTP/AVP 101 a=cdsc: 2 video RTP/AVP 101
a=cpar: a=rtcp-mux a=cpar: a=rtcp-mux
In the above example,the category IDENTICAL is inherited for the cpar In this example, the category IDENTICAL is inherited for the cpar-
encapsulated rtcp-mux attribute. encapsulated "rtcp-mux" attribute.
14.2. RFC5939 Analysis 14.2. RFC 5939 Analysis
[RFC5939] defines a general SDP capability negotiation framework. It [RFC5939] defines a general SDP capability negotiation framework. It
also specifies how to provide transport protocols and SDP attributes also specifies how to provide transport protocols and SDP attributes
as capabilities and negotiate them using the framework. as capabilities and negotiate them using the framework.
For this purpose, [RFC5939] defines the following For this purpose, [RFC5939] defines the following:
o A set of capabilities for the session and its associated media * A set of capabilities for the session and its associated media-
stream components, supported by each side. The attribute stream components, supported by each side. The attribute "a=acap"
("a=acap") defines how to list an attribute name and its defines how to list an attribute name and its associated value (if
associated value (if any) as a capability. The attribute any) as a capability. The attribute "a=tcap" defines how to list
("a=tcap") defines how to list transport protocols (e.g., "RTP/ transport protocols (e.g., "RTP/AVP") as capabilities.
AVP") as capabilities.
o A set of potential configurations ("a=pcfg") provided by the * A set of potential configurations ("a=pcfg") provided by the
offerer to indicate which combinations of those capabilities can offerer to indicate which combinations of those capabilities can
be used for the session and its associated media stream be used for the session and its associated media stream
components. Potential configurations are not ready for use until components. Potential configurations are not ready for use until
fully negotiated. They provide an alternative that MAY be used, fully negotiated. They provide an alternative that MAY be used,
subject to SDP capability negotiation procedures. In particular subject to SDP capability-negotiation procedures. In particular,
the answerer MAY choose one of the potential configurations for the answerer MAY choose one of the potential configurations for
use as part of the current Offer/Answer exchange. use as part of the current offer/answer exchange.
o An actual configuration ("a=acfg") for the session and its * An actual configuration ("a=acfg") for the session and its
associated media stream components. The actual configuration associated media stream components. The actual configuration
identifies the potential configuration that was negotiated for identifies the potential configuration that was negotiated for
use. Use of an actual configuration does not require any further use. Use of an actual configuration does not require any further
negotiation. negotiation.
o A negotiation process that takes the current actual and the set of * A negotiation process that takes the current actual and the set of
potential configurations (combinations of capabilities) as input potential configurations (combinations of capabilities) as input
and provides the negotiated actual configurations as output. In and provides the negotiated actual configurations as output. In
[RFC5939] the negotiation process is done independently for each [RFC5939], the negotiation process is done independently for each
media description. media description.
14.2.1. Recommendation: Procedures for Potential Configuration Pairing 14.2.1. Recommendation: Procedures for Potential Configuration Pairing
This section provides recommendations for entities generating and This section provides recommendations for entities generating and
processing SDP under the generic capability negotiation framework as processing SDP under the generic capability-negotiation framework as
defined in [RFC5939] under the context of media stream multiplexing. defined in [RFC5939] under the context of media-stream multiplexing.
These recommendations are provided for the purposes of enabling the These recommendations are provided for the purposes of enabling the
Offerer to make sure that the generated potential configurations offerer to make sure that the generated potential configurations
between the multiplexed streams can (easily) be negotiated to be between the multiplexed streams can (easily) be negotiated to be
consistent between those streams. In particular, the procedures aim consistent between those streams. In particular, the procedures aim
to simplify Answerer's procedure to choose potential configurations to simplify the answerer's procedure for choosing potential
that are consistent across all the multiplexed media descriptions. configurations that are consistent across all the multiplexed media
descriptions.
A potential configuration selects a set of attributes and parameters A potential configuration selects a set of attributes and parameters
that become part of the media description when negotiated. When that become part of the media description when negotiated. When
multiplexing media descriptions with potential configurations multiplexing media descriptions with potential configurations
specified, there MAY be a need for coordinating this selection specified, there MAY be a need for coordinating this selection
between multiplexed media descriptions to ensure the right between multiplexed media descriptions to ensure the right
multiplexing behavior. multiplexing behavior.
Although it is possible to analyze the various potential Although it is possible to analyze the various potential
configurations in multiplexed media descriptions to find combinations configurations in multiplexed media descriptions to find combinations
that satisfy such constraints, it can quickly become complicated to that satisfy such constraints, it can quickly become complicated to
do so. do so.
The procedures defined in [RFC5939] state that each potential The procedures defined in [RFC5939] state that each potential
configuration in the SDP has a unique configuration number, however configuration in the SDP has a unique configuration number; however,
the scope of uniqueness is limited to each media description. To the scope of uniqueness is limited to each media description. To
make it simple for the answerer to chose valid combinations of make it simple for the answerer to chose valid combinations of
potential configurations across media descriptions in a given bundle potential configurations across media descriptions in a given BUNDLE
group, we provide a simple rule for constructing potential group, we provide a simple rule for constructing potential
configurations configurations:
o Let m-bundle be the set of media descriptions that form a given * Let m-bundle be the set of media descriptions that form a given
bundle . bundle.
o Let m-bundle-pcfg be the set of media descriptions in m-bundle * Let m-bundle-pcfg be the set of media descriptions in m-bundle
that include one or more potential configurations. that include one or more potential configurations.
o Each media description in m-bundle-pcfg MUST have at least one * Each media description in m-bundle-pcfg MUST have at least one
potential configuration with the same configuration number (e.g. potential configuration with the same configuration number (e.g.,
"1"). "1").
o For each potential configuration with configuration number x in m- * For each potential configuration with configuration number x in m-
bundle-pcfg, the offerer MUST ensure that if the answerer chooses bundle-pcfg, the offerer MUST ensure that if the answerer chooses
configuration number x in each of the media descriptions in m- configuration number x in each of the media descriptions in m-
bundle-pcfg, then the resulting SDP will have all multiplexing bundle-pcfg, then the resulting SDP will have all multiplexing
constraints satisfied for those media descriptions. constraints satisfied for those media descriptions.
o Since it is nearly impossible to define a generic mechanism for * Since it is nearly impossible to define a generic mechanism for
various capability extensions, this document does't provide various capability extensions, this document doesn't provide
procedures for dealing with the capability extension attributes. procedures for dealing with the capability-extension attributes.
However, Section 14.3 provide analysis of media capability However, Section 14.3 provides analysis of media-capability-
extension attributes as defined in [RFC6871]. extension attributes as defined in [RFC6871].
The above allows the answerer to easily find multiplexing compatible The above allows the answerer to easily find multiplexing-compatible
combinations of potential configurations: The answerer simply choses combinations of potential configurations. The answerer simply
a potential configuration (number) that is present in all of the chooses a potential configuration (number) that is present in all of
media descriptions with potential configurations in the bundle. the media descriptions with potential configurations in the bundle.
Note that it is still possible for the offerer to provide additional Note that it is still possible for the offerer to provide additional
potential configurations with independent configuration numbers. The potential configurations with independent configuration numbers. The
answerer will have to perform more complicated analysis to determine answerer will have to perform more complicated analysis to determine
valid multiplexed combinations of those. valid multiplexed combinations of those.
14.2.1.1. Example: Transport Capability Multiplexing 14.2.1.1. Example: Transport-Capability Multiplexing
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
a=tcap:1 RTP/SAVPF a=tcap:1 RTP/SAVPF
a=tcap:2 RTP/SAVP a=tcap:2 RTP/SAVP
a=group:BUNDLE audio video a=group:BUNDLE audio video
m=audio m=audio
a=mid:audio a=mid:audio
a=pcfg:1 t=1 a=pcfg:1 t=1
a=pcfg:2 a=pcfg:2
m=video m=video
a=mid:video a=mid:video
a=pcfg:1 t=1 a=pcfg:1 t=1
a=pcfg:2 t=2 a=pcfg:2 t=2
In the example above, the potential configurations that offer In this example, the potential configurations that offer transport-
transport protocol capability of RTP/SAVPF has the same configuration protocol capability of RTP/SAVPF have the same configuration number
number "1" in both the audio and video media descriptions. "1" in both the audio and video media descriptions.
14.2.1.2. Example: Attribute Capability Multiplexing 14.2.1.2. Example: Attribute-Capability Multiplexing
v=0 v=0
o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com o=alice 2890844526 2890844527 IN IP4 host.atlanta.example.com
s= s=
c=IN IP4 host.atlanta.example.com c=IN IP4 host.atlanta.example.com
t=0 0 t=0 0
a=acap:1 a=rtcp-mux a=acap:1 a=rtcp-mux
a=acap:2 a=crypto:1 AES_CM_128_HMAC_SHA1_80 a=acap:2 a=crypto:1 AES_CM_128_HMAC_SHA1_80
inline:EcGZiNWpFJhQXdspcl1ekcmVCNWpVLcfHAwJSoj|2^20|1:32 inline:EcGZiNWpFJhQXdspcl1ekcmVCNWpVLcfHAwJSoj|2^20|1:32
a=group:BUNDLE audio video a=group:BUNDLE audio video
m=audio 49172 RTP/AVP 99 m=audio 49172 RTP/AVP 99
a=mid:audio a=mid:audio
a=pcfg:1 a=1 a=pcfg:1 a=1
a=pcfg:2 a=pcfg:2
m=video 560024 RTP/AVP 100 m=video 560024 RTP/AVP 100
a=mid:video a=mid:video
a=pcfg:1 a=1 a=pcfg:1 a=1
a=pcfg:2 a=2 a=pcfg:2 a=2
In the example above, the potential configuration number "1" is In this example, the potential configuration number "1" is repeated
repeated while referring to attribute capability a=rtcp-mux, since while referring to attribute capability a=rtcp-mux, since the
the behavior is IDENTICAL for the attribute a=rtcp-mux under behavior is IDENTICAL for the attribute a=rtcp-mux under
multiplexing. multiplexing.
14.3. RFC6871 Analysis 14.3. RFC 6871 Analysis
[RFC6871] extends the capability negotiation framework described in [RFC6871] extends the capability negotiation framework described in
[RFC5939] by defining media capabilities that can be used to indicate [RFC5939] by defining media capabilities that can be used to indicate
and negotiate media types and their associated format parameters. It and negotiate media types and their associated format parameters. It
also allows indication of latent configurations and session also allows indication of latent configurations and session
capabilities. capabilities.
14.3.1. Recommendation: Dealing with Payload Type Numbers 14.3.1. Recommendation: Dealing with Payload Type Numbers
[RFC6871] defines a new payload type ("pt") parameter to be used with [RFC6871] defines a new payload type parameter ("pt") to be used with
the potential, actual, and latent configuration parameters. The the potential, actual, and latent configuration parameters. The
parameter associates RTP payload type numbers with the referenced parameter associates RTP payload type numbers with the referenced
RTP-based media format capabilities ("a=rmcap") defined in [RFC6871] RTP-based media-format capabilities ("a=rmcap") defined in [RFC6871]
and is appropriate only when the transport protocol uses RTP. This and is appropriate only when the transport protocol uses RTP. This
means that the same payload type number can be assigned as part of means that the same payload type number can be assigned as part of
potential or actual configurations in different media descriptions in potential or actual configurations in different media descriptions in
a bundle. There are rules for the usage of identical Payload Type a bundle. There are rules for the usage of identical payload type
values across multiplexed "m=" lines as described in values across multiplexed "m=" lines, described in [RFC8843], which
[I-D.ietf-mmusic-sdp-bundle-negotiation], which must be followed here must be followed here, as well. As described in Section 14.2.1, the
as well. As described in Section 14.2.1, the use of identical use of identical configuration numbers for compatible configurations
configuration numbers for compatible configurations in different in different media descriptions that are part of the bundle provides
media descriptions that are part of the bundle provides a way to a way to ensure that the answerer can easily pick compatible
ensure that the answerer can easily pick compatible configurations configurations here, as well.
here as well.
14.3.1.1. Example: Attribute Capability Under Shared Payload Type 14.3.1.1. Example: Attribute Capability under Shared Payload Type
The attributes (a=rmcap, a=mfcap) follow the above recommendations The attributes "a=rmcap" and "a=mfcap" follow the above
under multiplexing. recommendations under multiplexing.
v=0 v=0
o=- 25678 753849 IN IP4 192.0.2.1 o=- 25678 753849 IN IP4 192.0.2.1
s= s=
c=IN IP4 192.0.2.1 c=IN IP4 192.0.2.1
t=0 0 t=0 0
a=creq:med-v0 a=creq:med-v0
m=audio 54322 RTP/AVP 96 m=audio 54322 RTP/AVP 96
a=rtpmap:96 AMR-WB/16000/1 a=rtpmap:96 AMR-WB/16000/1
a=fmtp:96 mode-change-capability=1; max-red=220; a=fmtp:96 mode-change-capability=1; max-red=220;
skipping to change at page 69, line 41 skipping to change at line 2995
a=rtpmap:96 AMR-WB/16000/1 a=rtpmap:96 AMR-WB/16000/1
a=fmtp:96 mode-change-capability=1; max-red=220; a=fmtp:96 mode-change-capability=1; max-red=220;
mode-set=0,2,4,7 mode-set=0,2,4,7
a=rmcap:4 audio AMR/8000/1 a=rmcap:4 audio AMR/8000/1
a=rmcap:5 audio OPUS/48000/2 a=rmcap:5 audio OPUS/48000/2
a=mfcap:5 minptime=40 a=mfcap:5 minptime=40
a=mfcap:4 mode-change-capability=1 a=mfcap:4 mode-change-capability=1
a=pcfg:1 m=4 pt=4:97 a=pcfg:1 m=4 pt=4:97
a=pcfg:4 m=5 pt=5:101 a=pcfg:4 m=5 pt=5:101
In the example above, the potential configuration number "1" is In this example, the potential configuration number "1" is repeated
repeated when referring to media and media format capability used for when referring to media and media-format capability used for the
the Payload Type 96. This implies that both the media capability 2 Payload Type 96. This implies that both media capabilities 2 and 4,
and 4 along with their media format capabilities MUST refer to the along with their media-format capabilities, MUST refer to the same
same codec configuration, as per the definition of IDENTICAL-PER-PT. codec configuration, as per the definition of IDENTICAL-PER-PT.
14.3.2. Recommendation: Dealing with Latent Configurations 14.3.2. Recommendation: Dealing with Latent Configurations
[RFC6871] adds the notion of a latent configurations, which provides [RFC6871] adds the notion of a latent configuration that provides
configuration information that may be used to guide a subsequent configuration information that may be used to guide a subsequent
offer/exchange, e.g. by adding another media stream or use offer/exchange -- e.g., by adding another media stream or using
alternative codec combinations not currently offered. Latent alternative codec combinations not currently offered. Latent
configurations have configuration numbers which cannot overlap with configurations have configuration numbers that cannot overlap with
the potential configuration numbers [RFC6871]. Supported the potential configuration numbers [RFC6871]. Supported
combinations of potential and latent configurations are indicated by combinations of potential and latent configurations are indicated by
use of the "a=sescap" attribute, however use of this attribute is not use of the "a=sescap" attribute; however, use of this attribute is
recommended with multiplexed media, since it requires the use of not recommended with multiplexed media, since it requires the use of
unique configuration numbers across the SDP. Taken together, this unique configuration numbers across the SDP. Taken together, this
means there is no well-defined way to indicate supported combinations means there is no well-defined way to indicate supported combinations
of latent configurations, or combinations of latent and potential of latent configurations, or combinations of latent and potential
configurations with multiplexed media. It is still allowed to use configurations with multiplexed media. It is still allowed to use
the latent configuration attribute, however the limitations above the latent configuration attribute; however, the limitations above
will apply. To determine valid combinations, actual negotiation will will apply. To determine valid combinations, actual negotiation will
have to be attempted subsequently instead. have to be attempted subsequently instead.
15. IANA Considerations 15. IANA Considerations
[RFC EDITOR NOTE: Please replace RFCXXXX with the RFC number of this Section 15.1 defines a new subregistry, which has been added by the
document.] IANA, for identifying the initial registrations for various
multiplexing categories applicable, as described in this document.
Section 15.1 defines a new subregistry to be added by the IANA for
identifying the initial registrations for various multiplexing
categories applicable, as proposed in this document.
IANA is also requested to add a new column named "Mux Category" to
several of the subregistries in the "Session Description Protocol
(SDP) Parameters" registry. The tables in Section 15.2 identify name
of an entry in the existing subregistry and specify the value to be
put in the new "Mux Category" column of the associated IANA registry.
15.1. New 'Multiplexing Categories' subregistry IANA has added a new column named "Mux Category" to several of the
subregistries in the "Session Description Protocol (SDP) Parameters"
registry. The tables in Section 15.2 identify the names of entries
in the existing subregistry and specify the value to be put in the
new "Mux Category" column of the associated IANA registry for each.
A new sub-registry needs to be defined called the "Multiplexing 15.1. New "Multiplexing Categories" Subregistry
Categories", with the following registrations created initially:
"NORMAL", "CAUTION", "IDENTICAL", "TRANSPORT", "SUM", "INHERIT",
"IDENTICAL-PER-PT", "SPECIAL" and "TBD" as defined in this document.
Initial value registration for "Multiplexing Categories". A new subregistry has been created. It is called "Multiplexing
Categories" and has the following registrations initially:
+-------------------------+-----------+ +=========================+===========+
| Multiplexing Categories | Reference | | Multiplexing Categories | Reference |
+=========================+===========+
| NORMAL | RFC 8859 |
+-------------------------+-----------+ +-------------------------+-----------+
| NORMAL | RFCXXXX | | CAUTION | RFC 8859 |
| CAUTION | RFCXXXX | +-------------------------+-----------+
| IDENTICAL | RFCXXXX | | IDENTICAL | RFC 8859 |
| TRANSPORT | RFCXXXX | +-------------------------+-----------+
| SUM | RFCXXXX | | TRANSPORT | RFC 8859 |
| INHERIT | RFCXXXX | +-------------------------+-----------+
| IDENTICAL-PER-PT | RFCXXXX | | SUM | RFC 8859 |
| SPECIAL | RFCXXXX | +-------------------------+-----------+
| TBD | RFCXXXX | | INHERIT | RFC 8859 |
+-------------------------+-----------+ +-------------------------+-----------+
| IDENTICAL-PER-PT | RFC 8859 |
+-------------------------+-----------+
| SPECIAL | RFC 8859 |
+-------------------------+-----------+
| TBD | RFC 8859 |
+-------------------------+-----------+
Table 80
Further entries can be registered using Standard Actions policies Further entries can be registered using Standard Actions policies
outlined in [RFC5226], which requires IESG review and approval and outlined in [RFC8126], which requires IESG review and approval and
standards-track IETF RFC publication. Standards Track IETF RFC publication.
Each registration needs to indicate the multiplexing category value Each registration needs to indicate the multiplexing category value
to be added to the "Multiplexing Categories" subregistry as defined to be added to the "Multiplexing Categories" subregistry, as defined
in this section. in this section.
Such a registration MUST also indicate the applicability of the newly Such a registration MUST also indicate the applicability of the newly
defined multiplexing category value to various subregistries defined defined multiplexing category value to various subregistries defined
at the "Session Description Protocol (SDP) Parameters" registry. in the "Session Description Protocol (SDP) Parameters" registry.
15.2. 'Mux Category' column for subregistries 15.2. "Mux Category" Column for Subregistries
Each sub-section identifies a subregistry in the "Session Description Each subsection identifies a subregistry of the "Session Description
Protocol (SDP) Parameters" registry. The tables list the column that Protocol (SDP) Parameters" registry. The tables list the column that
identifies the SDP attribute name/Token/Value from the corresponding identifies the SDP attribute name/Token/Value from the corresponding
subregistries and the values to be used for the new "Mux Category" subregistries and the values to be used for the new "Mux Category"
column to be added. column to be added.
For the entries in the existing subregistries, under the "Session Entries in the existing subregistries of the "Session Description
Description Protocol (SDP) Parameters" registry, that lack a value Protocol (SDP) Parameters" registry that lack a value for the "Mux
for the "Mux Category" in this specification will get a value of Category" in this specification will get a value of "TBD".
"TBD".
The registration policy for updates to the 'Mux Category' column The registration policy for updates to the "Mux Category" column
values for existing parameters, or when registering new parameters, values for existing parameters, or when registering new parameters,
are beyond the scope of this document. The registration policy for is beyond the scope of this document. The registration policy for
the affected table is defined in [I-D.ietf-mmusic-rfc4566bis]. the affected table is defined in [RFC8866].
15.2.1. Table: SDP bwtype 15.2.1. Table: SDP bwtype
The following values are to be added to the 'SDP bwtype' subregistry The following values have been added to the "bwtype" subregistry of
in the "Session Description Protocol (SDP) Parameters" registry. The the "Session Description Protocol (SDP) Parameters" registry. The
references should be updated to point at this RFC as well as the references have been updated to point to this RFC as well as the
previous references. previous references.
+----------+--------------+ +==========+==============+
| SDP Name | Mux Category | | SDP Name | Mux Category |
+----------+--------------+ +==========+==============+
| CT | NORMAL | | CT | NORMAL |
+----------+--------------+
| AS | SUM | | AS | SUM |
+----------+--------------+
| RS | SUM | | RS | SUM |
+----------+--------------+
| RR | SUM | | RR | SUM |
+----------+--------------+
| TIAS | SPECIAL | | TIAS | SPECIAL |
+----------+--------------+ +----------+--------------+
15.2.2. Table: att-field (session level) Table 81
The following values are to be added to the "att-field (session 15.2.2. Table: attribute-name
level)" subregistry in the "Session Description Protocol (SDP)
Parameters" registry. The references should be updated to point at
this RFC as well as the previous references.
+---------------------+--------------+ The following values have been added to the "attribute-name"
| SDP Name | Mux Category | (formerly "att-field") subregistry of the "Session Description
+---------------------+--------------+ Protocol (SDP) Parameters" registry. The references have been
| cat | NORMAL | updated to point to this RFC as well as the previous references.
| keywds | NORMAL |
| type | NORMAL |
| type:broadcast | NORMAL |
| type:H332 | NORMAL |
| type:meeting | NORMAL |
| type:moderated | NORMAL |
| type:test | NORMAL |
| charset | NORMAL |
| charset:iso8895-1 | NORMAL |
| tool | NORMAL |
| ipbcp | SPECIAL |
| group | NORMAL |
| ice-lite | NORMAL |
| ice-options | NORMAL |
| bcastversion | NORMAL |
| 3GPP-Integrity-Key | CAUTION |
| 3GPP-SDP-Auth | CAUTION |
| alt-group | CAUTION |
| PSCid | NORMAL |
| bc_service | NORMAL |
| bc_program | NORMAL |
| bc_service_package | NORMAL |
| sescap | CAUTION |
| rtsp-ice-d-m | TBD |
+---------------------+--------------+
15.2.3. Table: att-field (both session and media level) NOTE: The attributes from [FLUTE] ("flute-tsi", "flute-ch", "FEC-
declaration", "FEC-OTI-extension", "content-desc") were not analyzed
for their multiplexing behavior, due to the expired status of the
draft. For the purposes of this specification, the multiplexing
category of "TBD" is assigned.
The following values are to be added to the "att-field (both session +==========================+==================+
and media level)" subregistry in the "Session Description Protocol | SDP Name | Mux Category |
(SDP) Parameters" registry. The references should be updated to +==========================+==================+
point at this RFC as well as the previous references. | cat | NORMAL |
+--------------------------+------------------+
| keywds | NORMAL |
+--------------------------+------------------+
| type | NORMAL |
+--------------------------+------------------+
| type:broadcast | NORMAL |
+--------------------------+------------------+
| type:H332 | NORMAL |
+--------------------------+------------------+
| type:meeting | NORMAL |
+--------------------------+------------------+
| type:moderated | NORMAL |
+--------------------------+------------------+
| type:test | NORMAL |
+--------------------------+------------------+
| charset | NORMAL |
+--------------------------+------------------+
| charset:iso8895-1 | NORMAL |
+--------------------------+------------------+
| tool | NORMAL |
+--------------------------+------------------+
| ipbcp | SPECIAL |
+--------------------------+------------------+
| group | NORMAL |
+--------------------------+------------------+
| ice-lite | NORMAL |
+--------------------------+------------------+
| ice-options | NORMAL |
+--------------------------+------------------+
| bcastversion | NORMAL |
+--------------------------+------------------+
| 3GPP-Integrity-Key | CAUTION |
+--------------------------+------------------+
| 3GPP-SDP-Auth | CAUTION |
+--------------------------+------------------+
| alt-group | CAUTION |
+--------------------------+------------------+
| PSCid | NORMAL |
+--------------------------+------------------+
| bc_service | NORMAL |
+--------------------------+------------------+
| bc_program | NORMAL |
+--------------------------+------------------+
| bc_service_package | NORMAL |
+--------------------------+------------------+
| sescap | CAUTION |
+--------------------------+------------------+
| rtsp-ice-d-m | TBD |
+--------------------------+------------------+
| recvonly | NORMAL |
+--------------------------+------------------+
| sendrecv | NORMAL |
+--------------------------+------------------+
| sendonly | NORMAL |
+--------------------------+------------------+
| sdplang | NORMAL |
+--------------------------+------------------+
| lang | NORMAL |
+--------------------------+------------------+
| h248item | SPECIAL |
+--------------------------+------------------+
| sqn | NORMAL |
+--------------------------+------------------+
| cdsc | NORMAL |
+--------------------------+------------------+
| cpar | INHERIT |
+--------------------------+------------------+
| cparmin | SPECIAL |
+--------------------------+------------------+
| cparmax | SPECIAL |
+--------------------------+------------------+
| rtcp-xr | NORMAL |
+--------------------------+------------------+
| maxprate | SPECIAL |
+--------------------------+------------------+
| setup | TRANSPORT |
+--------------------------+------------------+
| connection | TRANSPORT |
+--------------------------+------------------+
| key-mgmt | IDENTICAL |
+--------------------------+------------------+
| source-filter | IDENTICAL |
+--------------------------+------------------+
| inactive | NORMAL |
+--------------------------+------------------+
| fingerprint | TRANSPORT |
+--------------------------+------------------+
| flute-tsi | TBD |
+--------------------------+------------------+
| flute-ch | TBD |
+--------------------------+------------------+
| FEC-declaration | TBD |
+--------------------------+------------------+
| FEC-OTI-extension | TBD |
+--------------------------+------------------+
| content-desc | TBD |
+--------------------------+------------------+
| ice-pwd | TRANSPORT |
+--------------------------+------------------+
| ice-ufrag | TRANSPORT |
+--------------------------+------------------+
| stkmstream | NORMAL |
+--------------------------+------------------+
| extmap | SPECIAL |
+--------------------------+------------------+
| qos-mech-send | TRANSPORT |
+--------------------------+------------------+
| qos-mech-recv | TRANSPORT |
+--------------------------+------------------+
| csup | NORMAL |
+--------------------------+------------------+
| creq | NORMAL |
+--------------------------+------------------+
| acap | INHERIT |
+--------------------------+------------------+
| tcap | INHERIT |
+--------------------------+------------------+
| 3GPP-QoE-Metrics | CAUTION |
+--------------------------+------------------+
| 3GPP-Asset-Information | CAUTION |
+--------------------------+------------------+
| mbms-mode | CAUTION |
+--------------------------+------------------+
| mbms-repair | CAUTION |
+--------------------------+------------------+
| ike-setup | IDENTICAL |
+--------------------------+------------------+
| psk-fingerprint | IDENTICAL |
+--------------------------+------------------+
| multicast-rtcp | IDENTICAL |
+--------------------------+------------------+
| rmcap | IDENTICAL-PER-PT |
+--------------------------+------------------+
| omcap | NORMAL |
+--------------------------+------------------+
| mfcap | IDENTICAL-PER-PT |
+--------------------------+------------------+
| mscap | INHERIT |
+--------------------------+------------------+
| 3gpp.iut.replication | TBD |
+--------------------------+------------------+
| bcap | INHERIT |
+--------------------------+------------------+
| ccap | IDENTICAL |
+--------------------------+------------------+
| icap | NORMAL |
+--------------------------+------------------+
| etag | CAUTION |
+--------------------------+------------------+
| duplication-delay | NORMAL |
+--------------------------+------------------+
| range | CAUTION |
+--------------------------+------------------+
| control | CAUTION |
+--------------------------+------------------+
| mtag | CAUTION |
+--------------------------+------------------+
| ts-refclk | NORMAL |
+--------------------------+------------------+
| mediaclk | NORMAL |
+--------------------------+------------------+
| calgextmap | NORMAL |
+--------------------------+------------------+
| ptime | IDENTICAL-PER-PT |
+--------------------------+------------------+
| orient | NORMAL |
+--------------------------+------------------+
| orient:portrait | NORMAL |
+--------------------------+------------------+
| orient:landscape | NORMAL |
+--------------------------+------------------+
| orient:seascape | NORMAL |
+--------------------------+------------------+
| framerate | IDENTICAL-PER-PT |
+--------------------------+------------------+
| quality | NORMAL |
+--------------------------+------------------+
| rtpmap | IDENTICAL-PER-PT |
+--------------------------+------------------+
| fmtp | IDENTICAL-PER-PT |
+--------------------------+------------------+
| rtpred1 | CAUTION |
+--------------------------+------------------+
| rtpred2 | CAUTION |
+--------------------------+------------------+
| T38FaxVersion | TBD |
+--------------------------+------------------+
| T38MaxBitRate | TBD |
+--------------------------+------------------+
| T38FaxFillBitRemoval | TBD |
+--------------------------+------------------+
| T38FaxTranscodingMMR | TBD |
+--------------------------+------------------+
| T38FaxTranscodingJBIG | TBD |
+--------------------------+------------------+
| T38FaxRateManagement | TBD |
+--------------------------+------------------+
| T38FaxMaxBuffer | TBD |
+--------------------------+------------------+
| T38FaxMaxDatagram | TBD |
+--------------------------+------------------+
| T38FaxUdpEC | TBD |
+--------------------------+------------------+
| maxptime | IDENTICAL-PER-PT |
+--------------------------+------------------+
| des | CAUTION |
+--------------------------+------------------+
| curr | CAUTION |
+--------------------------+------------------+
| conf | CAUTION |
+--------------------------+------------------+
| mid | NORMAL |
+--------------------------+------------------+
| rtcp | TRANSPORT |
+--------------------------+------------------+
| rtcp-fb | IDENTICAL-PER-PT |
+--------------------------+------------------+
| label | NORMAL |
+--------------------------+------------------+
| T38VendorInfo | TBD |
+--------------------------+------------------+
| crypto | TRANSPORT |
+--------------------------+------------------+
| eecid | CAUTION |
+--------------------------+------------------+
| aalType | CAUTION |
+--------------------------+------------------+
| capability | CAUTION |
+--------------------------+------------------+
| qosClass | CAUTION |
+--------------------------+------------------+
| bcob | CAUTION |
+--------------------------+------------------+
| stc | CAUTION |
+--------------------------+------------------+
| upcc | CAUTION |
+--------------------------+------------------+
| atmQOSparms | CAUTION |
+--------------------------+------------------+
| atmTrfcDesc | CAUTION |
+--------------------------+------------------+
| abrParms | CAUTION |
+--------------------------+------------------+
| abrSetup | CAUTION |
+--------------------------+------------------+
| bearerType | CAUTION |
+--------------------------+------------------+
| lij | CAUTION |
+--------------------------+------------------+
| anycast | CAUTION |
+--------------------------+------------------+
| cache | CAUTION |
+--------------------------+------------------+
| bearerSigIE | CAUTION |
+--------------------------+------------------+
| aalApp | CAUTION |
+--------------------------+------------------+
| cbrRate | CAUTION |
+--------------------------+------------------+
| sbc | CAUTION |
+--------------------------+------------------+
| clkrec | CAUTION |
+--------------------------+------------------+
| fec | CAUTION |
+--------------------------+------------------+
| prtfl | CAUTION |
+--------------------------+------------------+
| structure | CAUTION |
+--------------------------+------------------+
| cpsSDUsize | CAUTION |
+--------------------------+------------------+
| aal2CPS | CAUTION |
+--------------------------+------------------+
| aal2CPSSDUrate | CAUTION |
+--------------------------+------------------+
| aal2sscs3661unassured | CAUTION |
+--------------------------+------------------+
| aal2sscs3661assured | CAUTION |
+--------------------------+------------------+
| aal2sscs3662 | CAUTION |
+--------------------------+------------------+
| aal5sscop | CAUTION |
+--------------------------+------------------+
| atmmap | CAUTION |
+--------------------------+------------------+
| silenceSupp | CAUTION |
+--------------------------+------------------+
| ecan | CAUTION |
+--------------------------+------------------+
| gc | CAUTION |
+--------------------------+------------------+
| profileDesc | CAUTION |
+--------------------------+------------------+
| vsel | CAUTION |
+--------------------------+------------------+
| dsel | CAUTION |
+--------------------------+------------------+
| fsel | CAUTION |
+--------------------------+------------------+
| onewaySel | CAUTION |
+--------------------------+------------------+
| codecconfig | CAUTION |
+--------------------------+------------------+
| isup_usi | CAUTION |
+--------------------------+------------------+
| uiLayer1_Prot | CAUTION |
+--------------------------+------------------+
| chain | CAUTION |
+--------------------------+------------------+
| floorctrl | TBD |
+--------------------------+------------------+
| confid | TBD |
+--------------------------+------------------+
| userid | TBD |
+--------------------------+------------------+
| floorid | TBD |
+--------------------------+------------------+
| FEC | NORMAL |
+--------------------------+------------------+
| accept-types | TBD |
+--------------------------+------------------+
| accept-wrapped-types | TBD |
+--------------------------+------------------+
| max-size | TBD |
+--------------------------+------------------+
| path | TBD |
+--------------------------+------------------+
| dccp-service-code | CAUTION |
+--------------------------+------------------+
| rtcp-mux | IDENTICAL |
+--------------------------+------------------+
| candidate | TRANSPORT |
+--------------------------+------------------+
| ice-mismatch | NORMAL |
+--------------------------+------------------+
| remote-candidates | TRANSPORT |
+--------------------------+------------------+
| SRTPAuthentication | TBD |
+--------------------------+------------------+
| SRTPROCTxRate | TBD |
+--------------------------+------------------+
| rtcp-rsize | IDENTICAL |
+--------------------------+------------------+
| file-selector | TBD |
+--------------------------+------------------+
| file-transfer-id | TBD |
+--------------------------+------------------+
| file-disposition | TBD |
+--------------------------+------------------+
| file-date | TBD |
+--------------------------+------------------+
| file-icon | TBD |
+--------------------------+------------------+
| file-range | TBD |
+--------------------------+------------------+
| depend | IDENTICAL-PER-PT |
+--------------------------+------------------+
| ssrc | NORMAL |
+--------------------------+------------------+
| ssrc-group | NORMAL |
+--------------------------+------------------+
| rtcp-unicast | IDENTICAL |
+--------------------------+------------------+
| pcfg | SPECIAL |
+--------------------------+------------------+
| acfg | SPECIAL |
+--------------------------+------------------+
| zrtp-hash | TRANSPORT |
+--------------------------+------------------+
| X-predecbufsize | CAUTION |
+--------------------------+------------------+
| X-initpredecbufperiod | CAUTION |
+--------------------------+------------------+
| X-initpostdecbufperiod | CAUTION |
+--------------------------+------------------+
| X-decbyterate | CAUTION |
+--------------------------+------------------+
| 3gpp-videopostdecbufsize | CAUTION |
+--------------------------+------------------+
| framesize | CAUTION |
+--------------------------+------------------+
| 3GPP-SRTP-Config | CAUTION |
+--------------------------+------------------+
| alt | CAUTION |
+--------------------------+------------------+
| alt-default-id | CAUTION |
+--------------------------+------------------+
| 3GPP-Adaption-Support | CAUTION |
+--------------------------+------------------+
| mbms-flowid | CAUTION |
+--------------------------+------------------+
| fec-source-flow | SPECIAL |
+--------------------------+------------------+
| fec-repair-flow | SPECIAL |
+--------------------------+------------------+
| repair-window | SPECIAL |
+--------------------------+------------------+
| rams-updates | CAUTION |
+--------------------------+------------------+
| imageattr | IDENTICAL-PER-PT |
+--------------------------+------------------+
| cfw-id | NORMAL |
+--------------------------+------------------+
| portmapping-req | CAUTION |
+--------------------------+------------------+
| ecn-capable-rtp | IDENTICAL |
+--------------------------+------------------+
| visited-realm | TRANSPORT |
+--------------------------+------------------+
| secondary-realm | TRANSPORT |
+--------------------------+------------------+
| omr-s-cksum | NORMAL |
+--------------------------+------------------+
| omr-m-cksum | NORMAL |
+--------------------------+------------------+
| omr-codecs | NORMAL |
+--------------------------+------------------+
| omr-m-att | NORMAL |
+--------------------------+------------------+
| omr-s-att | NORMAL |
+--------------------------+------------------+
| omr-m-bw | NORMAL |
+--------------------------+------------------+
| omr-s-bw | NORMAL |
+--------------------------+------------------+
| msrp-cema | TBD |
+--------------------------+------------------+
| dccp-port | CAUTION |
+--------------------------+------------------+
| resource | NORMAL |
+--------------------------+------------------+
| channel | NORMAL |
+--------------------------+------------------+
| cmid | NORMAL |
+--------------------------+------------------+
| content | NORMAL |
+--------------------------+------------------+
| lcfg | SPECIAL |
+--------------------------+------------------+
| loopback | NORMAL |
+--------------------------+------------------+
| loopback-source | NORMAL |
+--------------------------+------------------+
| loopback-mirror | NORMAL |
+--------------------------+------------------+
| chatroom | TBD |
+--------------------------+------------------+
| altc | TRANSPORT |
+--------------------------+------------------+
| T38FaxMaxIFP | TBD |
+--------------------------+------------------+
| T38FaxUdpECDepth | TBD |
+--------------------------+------------------+
| T38FaxUdpFECMaxSpan | TBD |
+--------------------------+------------------+
| T38ModemType | TBD |
+--------------------------+------------------+
| cs-correlation | TBD |
+--------------------------+------------------+
| rtcp-idms | NORMAL |
+--------------------------+------------------+
| cname | NORMAL |
+--------------------------+------------------+
| previous-ssrc | NORMAL |
+--------------------------+------------------+
| fmtp | IDENTICAL-PER-PT |
+--------------------------+------------------+
| ts-refclk | NORMAL |
+--------------------------+------------------+
| mediaclk | NORMAL |
+--------------------------+------------------+
NOTE: The attributes from draft-ietf-rmt-flute-sdp ('flute-tsi', Table 82
'flute-ch', 'FEC-declaration', 'FEC-OTI-extension', 'content-desc')
were not analyzed for their multiplexing behavior due to the expired
status of the draft. For purposes of this specification, the
multiplexing category of 'TBD' is assigned.
+-------------------------+-------------------+ 15.2.3. Table: content SDP Parameters
| SDP Name | Mux Category |
+-------------------------+-------------------+
| recvonly | NORMAL |
| sendrecv | NORMAL |
| sendonly | NORMAL |
| sdplang | NORMAL |
| lang | NORMAL |
| h248item | SPECIAL |
| sqn | NORMAL |
| cdsc | NORMAL |
| cpar | INHERIT |
| cparmin | SPECIAL |
| cparmax | SPECIAL |
| rtcp-xr | NORMAL |
| maxprate | SPECIAL |
| setup | TRANSPORT |
| connection | TRANSPORT |
| key-mgmt | IDENTICAL |
| source-filter | IDENTICAL |
| inactive | NORMAL |
| fingerprint | TRANSPORT |
| flute-tsi | TBD |
| flute-ch | TBD |
| FEC-declaration | TBD |
| FEC-OTI-extension | TBD |
| content-desc | TBD |
| ice-pwd | TRANSPORT |
| ice-ufrag | TRANSPORT |
| stkmstream | NORMAL |
| extmap | SPECIAL |
| qos-mech-send | TRANSPORT |
| qos-mech-recv | TRANSPORT |
| csup | NORMAL |
| creq | NORMAL |
| acap | INHERIT |
| tcap | INHERIT |
| 3GPP-QoE-Metrics | CAUTION |
| 3GPP-Asset-Information | CAUTION |
| mbms-mode | CAUTION |
| mbms-repair | CAUTION |
| ike-setup | IDENTICAL |
| psk-fingerprint | IDENTICAL |
| multicast-rtcp | IDENTICAL |
| rmcap | IDENTICAL-PER-PT |
| omcap | NORMAL |
| mfcap | IDENTICAL-PER-PT |
| mscap | INHERIT |
| 3gpp.iut.replication | TBD |
| bcap | INHERIT |
| ccap | IDENTICAL |
| icap | NORMAL |
| 3gpp_sync_info | NORMAL |
| 3gpp_MaxRecvSDUSize | NORMAL |
| etag | CAUTION |
| duplication-delay | NORMAL |
| range | CAUTION |
| control | CAUTION |
| mtag | CAUTION |
| ts-refclk | NORMAL |
| mediaclk | NORMAL |
| calgextmap | NORMAL |
+-------------------------+-------------------+
15.2.4. Table: att-field (media level only) The following values have been added to the "content SDP Parameters"
subregistry of the "Session Description Protocol (SDP) Parameters"
registry. The references have been updated to point to this RFC as
well as the previous references.
The following values are to be added to the "att-field (media level +============+==============+
only)" registry in the "Session Description Protocol (SDP) | SDP Name | Mux Category |
Parameters" registry. The references should be updated to point at +============+==============+
this RFC as well as the previous references. | slides | NORMAL |
+------------+--------------+
| speaker | NORMAL |
+------------+--------------+
| sl | NORMAL |
+------------+--------------+
| main | NORMAL |
+------------+--------------+
| alt | NORMAL |
+------------+--------------+
| g.3gpp.cat | NORMAL |
+------------+--------------+
| g.3gpp.crs | NORMAL |
+------------+--------------+
+---------------------------+-------------------+ Table 83
| SDP Name | Mux Category |
+---------------------------+-------------------+
| ptime | IDENTICAL-PER-PT |
| orient | NORMAL |
| orient:portrait | NORMAL |
| orient:landscape | NORMAL |
| orient:seascape | NORMAL |
| framerate | IDENTICAL-PER-PT |
| quality | NORMAL |
| rtpmap | IDENTICAL-PER-PT |
| fmtp | IDENTICAL-PER-PT |
| rtpred1 | CAUTION |
| rtpred2 | CAUTION |
| T38FaxVersion | TBD |
| T38MaxBitRate | TBD |
| T38FaxFillBitRemoval | TBD |
| T38FaxTranscodingMMR | TBD |
| T38FaxTranscodingJBIG | TBD |
| T38FaxRateManagement | TBD |
| T38FaxMaxBuffer | TBD |
| T38FaxMaxDatagram | TBD |
| T38FaxUdpEC | TBD |
| maxptime | IDENTICAL-PER-PT |
| des | CAUTION |
| curr | CAUTION |
| conf | CAUTION |
| mid | NORMAL |
| rtcp | TRANSPORT |
| rtcp-fb | IDENTICAL-PER-PT |
| label | NORMAL |
| T38VendorInfo | TBD |
| crypto | TRANSPORT |
| eecid | CAUTION |
| aalType | CAUTION |
| capability | CAUTION |
| qosClass | CAUTION |
| bcob | CAUTION |
| stc | CAUTION |
| upcc | CAUTION |
| atmQOSparms | CAUTION |
| atmTrfcDesc | CAUTION |
| abrParms | CAUTION |
| abrSetup | CAUTION |
| bearerType | CAUTION |
| lij | CAUTION |
| anycast | CAUTION |
| cache | CAUTION |
| bearerSigIE | CAUTION |
| aalApp | CAUTION |
| cbrRate | CAUTION |
| sbc | CAUTION |
| clkrec | CAUTION |
| fec | CAUTION |
| prtfl | CAUTION |
| structure | CAUTION |
| cpsSDUsize | CAUTION |
| all2CPS | CAUTION |
| all2CPSSDUrate | CAUTION |
| aal2sscs3661unassured | CAUTION |
| aal2sscs3661assured | CAUTION |
| aal2sscs3662 | CAUTION |
| aal5sscop | CAUTION |
| atmmap | CAUTION |
| silenceSupp | CAUTION |
| ecan | CAUTION |
| gc | CAUTION |
| profileDesc | CAUTION |
| vsel | CAUTION |
| dsel | CAUTION |
| fsel | CAUTION |
| onewaySel | CAUTION |
| codecconfig | CAUTION |
| isup_usi | CAUTION |
| uiLayer1_Prot | CAUTION |
| chain | CAUTION |
| floorctrl | TBD |
| confid | NORMAL |
| userid | NORMAL |
| floorid | NORMAL |
| FEC | NORMAL |
| accept-types | TBD |
| accept-wrapped-types | TBD |
| max-size | TBD |
| path | TBD |
| dccp-service-code | CAUTION |
| rtcp-mux | IDENTICAL |
| candidate | TRANSPORT |
| ice-mismatch | NORMAL |
| remote-candidates | TRANSPORT |
| SRTPAuthentication | TBD |
| SRTPROCTxRate | TBD |
| rtcp-rsize | IDENTICAL |
| file-selector | TBD |
| file-transfer-id | TBD |
| file-disposition | TBD |
| file-date | TBD |
| file-icon | TBD |
| file-range | TBD |
| depend | IDENTICAL-PER-PT |
| ssrc | NORMAL |
| ssrc-group | NORMAL |
| rtcp-unicast | IDENTICAL |
| pcfg | SPECIAL |
| acfg | SPECIAL |
| zrtp-hash | TRANSPORT |
| X-predecbufsize | CAUTION |
| X-initpredecbufperiod | CAUTION |
| X-initpostdecbufperiod | CAUTION |
| X-decbyterate | CAUTION |
| 3gpp-videopostdecbufsize | CAUTION |
| framesize | CAUTION |
| 3GPP-SRTP-Config | CAUTION |
| alt | CAUTION |
| alt-default-id | CAUTION |
| 3GPP-Adaption-Support | CAUTION |
| mbms-flowid | CAUTION |
| fec-source-flow | SPECIAL |
| fec-repair-flow | SPECIAL |
| repair-window | SPECIAL |
| rams-updates | CAUTION |
| imageattr | IDENTICAL-PER-PT |
| cfw-id | NORMAL |
| portmapping-req | CAUTION |
| ecn-capable-rtp | IDENTICAL |
| visited-realm | TRANSPORT |
| secondary-realm | TRANSPORT |
| omr-s-cksum | NORMAL |
| omr-m-cksum | NORMAL |
| omr-codecs | NORMAL |
| omr-m-att | NORMAL |
| omr-s-att | NORMAL |
| omr-m-bw | NORMAL |
| omr-s-bw | NORMAL |
| msrp-cema | TBD |
| dccp-port | CAUTION |
| resource | NORMAL |
| channel | NORMAL |
| cmid | NORMAL |
| content | NORMAL |
| lcfg | SPECIAL |
| loopback | NORMAL |
| loopback-source | NORMAL |
| loopback-mirror | NORMAL |
| chatroom | TBD |
| altc | TRANSPORT |
| T38FaxMaxIFP | TBD |
| T38FaxUdpECDepth | TBD |
| T38FaxUdpFECMaxSpan | TBD |
| T38ModemType | TBD |
| cs-correlation | TBD |
| rtcp-idms | NORMAL |
+---------------------------+-------------------+
15.2.5. Table: att-field (source level) 15.2.4. Table: Semantics for the "group" SDP Attribute
The following values are to be added to the "att-field (source The following values have been added to the "Semantics for the
level)" registry in the "Session Description Protocol (SDP) 'group' SDP Attribute" subregistry of the "Session Description
Parameters" registry. The references should be updated to point at Protocol (SDP) Parameters" registry. The references have been
this RFC as well as the previous references. updated to point to this RFC as well as the previous references.
+----------------+-------------------+ +========+==============+
| SDP Name | Mux Category | | Token | Mux Category |
+----------------+-------------------+ +========+==============+
| cname | NORMAL | | LS | NORMAL |
| previous-ssrc | NORMAL | +--------+--------------+
| fmtp | IDENTICAL-PER-PT | | FID | NORMAL |
| ts-refclk | NORMAL | +--------+--------------+
| mediaclk | NORMAL | | SRF | NORMAL |
+----------------+-------------------+ +--------+--------------+
| ANAT | CAUTION |
+--------+--------------+
| FEC | NORMAL |
+--------+--------------+
| FEC-FR | NORMAL |
+--------+--------------+
| CS | NORMAL |
+--------+--------------+
| DDP | NORMAL |
+--------+--------------+
| DUP | NORMAL |
+--------+--------------+
15.2.6. Table: content SDP Parameters Table 84
The following values are to be added to the "content SDP Parameters" 15.2.5. Table: "rtcp-fb" Attribute Values
subregistry in the "Session Description Protocol (SDP) Parameters"
registry. The references should be updated to point at this RFC as
well as the previous references.
+-------------+--------------+ The following values have been added to the "'rtcp-fb' Attribute
| SDP Name | Mux Category | Values" subregistry of the "Session Description Protocol (SDP)
+-------------+--------------+ Parameters" registry. The references have been updated to point to
| slides | NORMAL | this RFC as well as the previous references.
| speaker | NORMAL |
| sl | NORMAL |
| main | NORMAL |
| alt | NORMAL |
| g.3gpp.cat | NORMAL |
| g.3gpp.crs | NORMAL |
+-------------+--------------+
15.2.7. Table: Semantics for the 'group' SDP Attribute +============+==================+
| Value Name | Mux Category |
+============+==================+
| ack | IDENTICAL-PER-PT |
+------------+------------------+
| app | SPECIAL |
+------------+------------------+
| ccm | IDENTICAL-PER-PT |
+------------+------------------+
| nack | IDENTICAL-PER-PT |
+------------+------------------+
| trr-int | IDENTICAL-PER-PT |
+------------+------------------+
The following values are to be added to the "Semantics for the Table 85
"group" SDP Attribute" subregistry in the "Session Description
Protocol (SDP) Parameters" registry. The references should be
updated to point at this RFC as well as the previous references.
+---------+--------------+ 15.2.6. Table: "ack" and "nack" Attribute Values
| Token | Mux Category |
+---------+--------------+
| LS | NORMAL |
| FID | NORMAL |
| SRF | NORMAL |
| ANAT | CAUTION |
| FEC | NORMAL |
| FEC-FR | NORMAL |
| CS | NORMAL |
| DDP | NORMAL |
| DUP | NORMAL |
+---------+--------------+
15.2.8. Table: 'rtcp-fb' Attribute Values The following values have been added to the "'ack' and 'nack'
Attribute Values" subregistry of the "Session Description Protocol
(SDP) Parameters" registry. The references have been updated to
point to this RFC as well as the previous references.
The following values are to be added to the " 'rtcp-fb' Attribute +============+==================+
Values" subregistry in the "Session Description Protocol (SDP) | Value Name | Mux Category |
Parameters" registry. The references should be updated to point at +============+==================+
this RFC as well as the previous references. | sli | IDENTICAL-PER-PT |
+------------+------------------+
| pli | IDENTICAL-PER-PT |
+------------+------------------+
| rpsi | IDENTICAL-PER-PT |
+------------+------------------+
| app | SPECIAL |
+------------+------------------+
| rai | IDENTICAL-PER-PT |
+------------+------------------+
| tllei | IDENTICAL-PER-PT |
+------------+------------------+
| pslei | IDENTICAL-PER-PT |
+------------+------------------+
| ecn | IDENTICAL |
+------------+------------------+
+------------+-------------------+ Table 86
| Value Name | Mux Category |
+------------+-------------------+
| ack | IDENTICAL-PER-PT |
| app | SPECIAL |
| ccm | IDENTICAL-PER-PT |
| nack | IDENTICAL-PER-PT |
| trr-int | IDENTICAL-PER-PT |
+------------+-------------------+
15.2.9. Table: 'ack' and 'nack' Attribute Values 15.2.7. Table: "depend" SDP Attribute Values
The following values are to be added to the " 'ack' and 'nack' The following values have been added to the "'depend' SDP Attribute
Attribute Values" subregistry in the "Session Description Protocol Values" subregistry of the "Session Description Protocol (SDP)
(SDP) Parameters" registry. The references should be updated to Parameters" registry. The references have been updated to point to
point at this RFC as well as the previous references. this RFC as well as the previous references.
+------------+-------------------+ +=======+==================+
| Value Name | Mux Category | | Token | Mux Category |
+------------+-------------------+ +=======+==================+
| sli | IDENTICAL-PER-PT | | lay | IDENTICAL-PER-PT |
| pli | IDENTICAL-PER-PT | +-------+------------------+
| rpsi | IDENTICAL-PER-PT | | mdc | IDENTICAL-PER-PT |
| app | SPECIAL | +-------+------------------+
| rai | IDENTICAL-PER-PT |
| tllei | IDENTICAL-PER-PT |
| pslei | IDENTICAL-PER-PT |
| ecn | IDENTICAL |
+------------+-------------------+
15.2.10. Table: 'depend' SDP Attribute Values Table 87
The following values are to be added to the " 'depend' SDP Attribute 15.2.8. Table: "cs-correlation" Attribute Values
Values" subregistry in the "Session Description Protocol (SDP)
Parameters" registry. The references should be updated to point at
this RFC as well as the previous references.
+-------+-------------------+ The following values have been added to the "'cs-correlation'
| Token | Mux Category | Attribute Values" subregistry of the "Session Description Protocol
+-------+-------------------+ (SDP) Parameters" registry. The references have been updated to
| lay | IDENTICAL-PER-PT | point to this RFC as well as the previous references.
| mdc | IDENTICAL-PER-PT |
+-------+-------------------+
15.2.11. Table: 'cs-correlation' Attribute Values +==========+==============+
| Value | Mux Category |
+==========+==============+
| callerid | TBD |
+----------+--------------+
| uuie | TBD |
+----------+--------------+
| dtmf | TBD |
+----------+--------------+
| external | TBD |
+----------+--------------+
The following values are to be added to the " "cs-correlation" Table 88
Attribute Values" subregistry in the "Session Description Protocol
(SDP) Parameters" registry. The references should be updated to
point at this RFC as well as the previous references.
+-----------+--------------+ 15.2.9. Table: Semantics for the "ssrc-group" SDP Attribute
| Value | Mux Category |
+-----------+--------------+
| callerid | TBD |
| uuie | TBD |
| dtmf | TBD |
| external | TBD |
+-----------+--------------+
15.2.12. Table: Semantics for the 'ssrc-group' SDP Attribute The following values have been added to the "Semantics for the 'ssrc-
group' SDP Attribute" subregistry of the "Session Description
Protocol (SDP) Parameters" registry. The references have been
updated to point to this RFC as well as the previous references.
The following values are to be added to the Semantics for the +========+==============+
"Semantics for the "ssrc-group" SDP Attribute" subregistry in the | Token | Mux Category |
"Session Description Protocol (SDP) Parameters" registry. The +========+==============+
references should be updated to point at this RFC as well as the | FID | NORMAL |
previous references. +--------+--------------+
| FEC | NORMAL |
+--------+--------------+
| FEC-FR | NORMAL |
+--------+--------------+
| DUP | NORMAL |
+--------+--------------+
+---------+--------------+ Table 89
| Token | Mux Category |
+---------+--------------+
| FID | NORMAL |
| FEC | NORMAL |
| FEC-FR | NORMAL |
| DUP | NORMAL |
+---------+--------------+
15.2.13. Table: SDP/RTSP key management protocol identifiers 15.2.10. Table: SDP/RTSP Key Management Protocol Identifiers
The following values are to be added to the "SDP/RTSP key management The following values have been added to the "SDP/RTSP key management
protocol identifiers" subregistry in the "Session Description protocol identifiers" subregistry of the "Session Description
Protocol (SDP) Parameters" registry. The references should be Protocol (SDP) Parameters" registry. The references have been
updated to point at this RFC as well as the previous references. updated to point to this RFC as well as the previous references.
+------------+--------------+ +============+==============+
| Value Name | Mux Category | | Value Name | Mux Category |
+------------+--------------+ +============+==============+
| mikey | IDENTICAL | | mikey | IDENTICAL |
+------------+--------------+ +------------+--------------+
15.2.14. Table: Codec Control Messages Table 90
The following values are to be added to the "Codec Control Messages" 15.2.11. Table: Codec Control Messages
subregistry in the "Session Description Protocol (SDP) Parameters"
registry. The references should be updated to point at this RFC as The following values have been added to the "Codec Control Messages"
subregistry of the "Session Description Protocol (SDP) Parameters"
registry. The references have been updated to point to this RFC as
well as the previous references. well as the previous references.
+------------+-------------------+ +============+==================+
| Value Name | Mux Category | | Value Name | Mux Category |
+------------+-------------------+ +============+==================+
| fir | IDENTICAL-PER-PT | | fir | IDENTICAL-PER-PT |
| tmmbr | IDENTICAL-PER-PT | +------------+------------------+
| tstr | IDENTICAL-PER-PT | | tmmbr | IDENTICAL-PER-PT |
| vbcm | IDENTICAL-PER-PT | +------------+------------------+
+------------+-------------------+ | tstr | IDENTICAL-PER-PT |
+------------+------------------+
| vbcm | IDENTICAL-PER-PT |
+------------+------------------+
15.2.15. Table: QoS Mechanism Tokens Table 91
The following values are to be added to the "QoS Mechanism Tokens" 15.2.12. Table: QoS Mechanism Tokens
subregistry in the "Session Description Protocol (SDP) Parameters"
registry. The references should be updated to point at this RFC as The following values have been added to the "QoS Mechanism Tokens"
subregistry of the "Session Description Protocol (SDP) Parameters"
registry. The references have been updated to point to this RFC as
well as the previous references. well as the previous references.
+---------------+--------------+ +===============+==============+
| QoS Mechanism | Mux Category | | QoS Mechanism | Mux Category |
+---------------+--------------+ +===============+==============+
| rsvp | TRANSPORT | | rsvp | TRANSPORT |
+---------------+--------------+
| nsis | TRANSPORT | | nsis | TRANSPORT |
+---------------+--------------+ +---------------+--------------+
15.2.16. Table: SDP Capability Negotiation Option Tags Table 92
The following values are to be added to the "SDP Capability 15.2.13. Table: SDP Capability Negotiation Option Tags
Negotiation Option Tags" subregistry in the "Session Description
Protocol (SDP) Parameters" registry. The references should be
updated to point at this RFC as well as the previous references.
+------------+--------------+ The following values have been added to the "SDP Capability
Negotiation Option Tags" subregistry of the "Session Description
Protocol (SDP) Parameters" registry. The references have been
updated to point to this RFC as well as the previous references.
+============+==============+
| Option Tag | Mux Category | | Option Tag | Mux Category |
+------------+--------------+ +============+==============+
| cap-v0 | NORMAL | | cap-v0 | NORMAL |
+------------+--------------+
| med-v0 | NORMAL | | med-v0 | NORMAL |
+------------+--------------+
| bcap-v0 | NORMAL | | bcap-v0 | NORMAL |
+------------+--------------+
| ccap-v0 | NORMAL | | ccap-v0 | NORMAL |
+------------+--------------+
| icap-v0 | NORMAL | | icap-v0 | NORMAL |
+------------+--------------+ +------------+--------------+
15.2.17. Table: Timestamp Reference Clock Source Parameters Table 93
The following values are to be added to the "Timestamp Reference
Clock Source Parameters" subregistry in the "Session Description
Protocol (SDP) Parameters" registry. The references should be
updated to point at this RFC as well as the previous references.
+----------+--------------+
| Name | Mux Category |
+----------+--------------+
| ntp | NORMAL |
| ptp | NORMAL |
| gps | NORMAL |
| gal | NORMAL |
| glonass | NORMAL |
| local | NORMAL |
| private | NORMAL |
+----------+--------------+
15.2.18. Table: Media Clock Source Parameters
The following values are to be added to the "Media Clock Source
Parameters" subegistry in the "Session Description Protocol (SDP)
Parameters" registry. The references should be updated to point at
this RFC as well as the previous references.
+-----------+--------------+
| Name | Mux Category |
+-----------+--------------+
| sender | NORMAL