draft-ietf-ecrit-unauthenticated-access-05.txt   draft-ietf-ecrit-unauthenticated-access-06.txt 
ECRIT H. Schulzrinne ECRIT H. Schulzrinne
Internet-Draft Columbia University Internet-Draft Columbia University
Intended status: Standards Track S. McCann Intended status: Standards Track S. McCann
Expires: March 13, 2013 Research in Motion UK Ltd Expires: November 01, 2013 Research in Motion UK Ltd
G. Bajko G. Bajko
Nokia Nokia
H. Tschofenig H. Tschofenig
Nokia Siemens Networks Nokia Siemens Networks
D. Kroeselberg D. Kroeselberg
Siemens Siemens
September 12, 2012 April 30, 2013
Extensions to the Emergency Services Architecture for dealing with Extensions to the Emergency Services Architecture for dealing with
Unauthenticated and Unauthorized Devices Unauthenticated and Unauthorized Devices
draft-ietf-ecrit-unauthenticated-access-05.txt draft-ietf-ecrit-unauthenticated-access-06.txt
Abstract Abstract
The IETF emergency services architecture assumes that the calling The IETF emergency services architecture assumes that the calling
device has acquired rights to use the access network or that no device has acquired rights to use the access network or that no
authentication is required for the access network, such as for public authentication is required for the access network, such as for public
wireless access points. Subsequent protocol interactions, such as wireless access points. Subsequent protocol interactions, such as
obtaining location information, learning the address of the Public obtaining location information, learning the address of the Public
Safety Answering Point (PSAP) and the emergency call itself are Safety Answering Point (PSAP) and the emergency call itself are
largely decoupled from the underlying network access procedures. largely decoupled from the underlying network access procedures.
In some cases, however, the device does not have these credentials In some cases, however, the device does not have these credentials
for network access, does not have a VoIP service provider, or the for network access, does not have a VoIP service provider, or the
credentials have become invalid, e.g., because the user has exhausted credentials have become invalid, e.g., because the user has exhausted
their prepaid balance or the account has expired. their prepaid balance or the account has expired.
This document provides a problem statement, introduces terminology This document provides a problem statement, introduces terminology
and describes an extension for the base IETF emergency services and describes an extension for the base IETF emergency services
architecture to address these scenarios. architecture to address these scenarios.
Status of this Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 13, 2013. This Internet-Draft will expire on November 01, 2013.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Use Case Categories . . . . . . . . . . . . . . . . . . . . . 8 3. Use Case Categories . . . . . . . . . . . . . . . . . . . . . 5
4. ZBP Considerations . . . . . . . . . . . . . . . . . . . . . . 10 4. ZBP Considerations . . . . . . . . . . . . . . . . . . . . . 7
5. NASP Considerations . . . . . . . . . . . . . . . . . . . . . 11 5. NASP Considerations . . . . . . . . . . . . . . . . . . . . . 7
5.1. End Host Profile . . . . . . . . . . . . . . . . . . . . . 13 5.1. End Host Profile . . . . . . . . . . . . . . . . . . . . 9
5.1.1. LoST Server Discovery . . . . . . . . . . . . . . . . 13 5.1.1. LoST Server Discovery . . . . . . . . . . . . . . . . 9
5.1.2. ESRP Discovery . . . . . . . . . . . . . . . . . . . . 13 5.1.2. ESRP Discovery . . . . . . . . . . . . . . . . . . . 9
5.1.3. Location Determination and Location Configuration . . 13 5.1.3. Location Determination and Location Configuration . . 9
5.1.4. Emergency Call Identification . . . . . . . . . . . . 13 5.1.4. Emergency Call Identification . . . . . . . . . . . . 10
5.1.5. SIP Emergency Call Signaling . . . . . . . . . . . . . 13 5.1.5. SIP Emergency Call Signaling . . . . . . . . . . . . 10
5.1.6. Media . . . . . . . . . . . . . . . . . . . . . . . . 14 5.1.6. Media . . . . . . . . . . . . . . . . . . . . . . . . 10
5.1.7. Testing . . . . . . . . . . . . . . . . . . . . . . . 14 5.1.7. Testing . . . . . . . . . . . . . . . . . . . . . . . 10
5.2. IAP/ISP Profile . . . . . . . . . . . . . . . . . . . . . 14 5.2. IAP/ISP Profile . . . . . . . . . . . . . . . . . . . . . 11
5.2.1. ESRP Discovery . . . . . . . . . . . . . . . . . . . . 14 5.2.1. ESRP Discovery . . . . . . . . . . . . . . . . . . . 11
5.2.2. Location Determination and Location Configuration . . 14 5.2.2. Location Determination and Location Configuration . . 11
5.3. ESRP Profile . . . . . . . . . . . . . . . . . . . . . . . 14 5.3. ESRP Profile . . . . . . . . . . . . . . . . . . . . . . 11
5.3.1. Emergency Call Routing . . . . . . . . . . . . . . . . 14 5.3.1. Emergency Call Routing . . . . . . . . . . . . . . . 11
5.3.2. Emergency Call Identification . . . . . . . . . . . . 14 5.3.2. Emergency Call Identification . . . . . . . . . . . . 11
5.3.3. SIP Emergency Call Signaling . . . . . . . . . . . . . 15 5.3.3. SIP Emergency Call Signaling . . . . . . . . . . . . 11
6. Lower Layer Considerations for NAA Case . . . . . . . . . . . 16 6. Lower Layer Considerations for NAA Case . . . . . . . . . . . 11
6.1. Link Layer Emergency Indication . . . . . . . . . . . . . 16 6.1. Link Layer Emergency Indication . . . . . . . . . . . . . 12
6.2. Securing Network Attachment in NAA Cases . . . . . . . . . 17 6.2. Securing Network Attachment in NAA Cases . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 20 7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 21 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
10.1. Normative References . . . . . . . . . . . . . . . . . . . 23 10.1. Normative References . . . . . . . . . . . . . . . . . . 16
10.2. Informative References . . . . . . . . . . . . . . . . . . 23 10.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction 1. Introduction
Summoning police, the fire department or an ambulance in emergencies Summoning police, the fire department or an ambulance in emergencies
is one of the fundamental and most-valued functions of the telephone. is one of the fundamental and most-valued functions of the telephone.
As telephone functionality moves from circuit-switched telephony to As telephone functionality moves from circuit-switched telephony to
Internet telephony, its users rightfully expect that this core Internet telephony, its users rightfully expect that this core
functionality will continue to work at least as well as it has for functionality will continue to work at least as well as it has for
the older technology. New devices and services are being made the older technology. New devices and services are being made
available that could be used to make a request for help, which are available that could be used to make a request for help, which are
skipping to change at page 5, line 48 skipping to change at page 5, line 13
environments. environments.
There are also indications that the functionality of unauthenticated There are also indications that the functionality of unauthenticated
emergency calls (called SIM-less calls) in today's cellular system in emergency calls (called SIM-less calls) in today's cellular system in
certain countries leads to a fair amount of hoax or test calls. This certain countries leads to a fair amount of hoax or test calls. This
causes overload situations at PSAPs which is considered harmful to causes overload situations at PSAPs which is considered harmful to
the overall availability and reliability of emergency services. the overall availability and reliability of emergency services.
As an example, Federal Office of Communications (OFCOM, Switzerland) As an example, Federal Office of Communications (OFCOM, Switzerland)
provided statistics about emergency (112) calls in Switzerland from provided statistics about emergency (112) calls in Switzerland from
Jan. 1997 to Nov. 2001. Switzerland did not offer SIM-less emergency Jan. 1997 to Nov. 2001. Switzerland did not offer SIM-less
calls except for almost a month in July 2000 where a significant emergency calls except for almost a month in July 2000 where a
increase in hoax and test calls was reported. As a consequence, the significant increase in hoax and test calls was reported. As a
functionality was disabled again. More details can be found in the consequence, the functionality was disabled again. More details can
panel presentations of the 3rd SDO Emergency Services Workshop be found in the panel presentations of the 3rd SDO Emergency Services
[esw07]. Workshop [esw07].
2. Terminology 2. Terminology
In this document, the key words "MUST", "MUST NOT", "REQUIRED", In this document, the key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
and "OPTIONAL" are to be interpreted as described in RFC 2119 and "OPTIONAL" are to be interpreted as described in RFC 2119
[RFC2119]. [RFC2119].
This document reuses terminology from [RFC5687] and [RFC5012], namely This document reuses terminology from [RFC5687] and [RFC5012], namely
Internet Access Provider (IAP), Internet Service Provider (ISP), Internet Access Provider (IAP), Internet Service Provider (ISP),
skipping to change at page 12, line 5 skipping to change at page 8, line 41
o The PSAP evaluates the initial INVITE and aims to complete the o The PSAP evaluates the initial INVITE and aims to complete the
call setup. call setup.
o Finally, when the call setup is completed media traffic can be o Finally, when the call setup is completed media traffic can be
exchanged between the PSAP and the SIP UA. exchanged between the PSAP and the SIP UA.
For editorial reasons the end-to-end SIP and media exchange between For editorial reasons the end-to-end SIP and media exchange between
the PSAP and SIP UA are not shown in Figure 2. the PSAP and SIP UA are not shown in Figure 2.
+-------+ +-------+
| PSAP | | PSAP |
| | | |
+-------+ +-------+
^ ^
| (8) | (8)
| |
+----------+(7) +----------+ +----------+(7) +----------+
| LoST |<-->| ESRP | | LoST |<-->| ESRP |
| Server | | | | Server | | |
+----------+ +----------+ +----------+ +----------+
^ ^ ^ ^
+----------------+----------------|--------------+
| ISP | | | +----------------+----------------|--------------+
|+----------+ | | +----------+| | ISP | | |
|| LCS-ISP | (3)| | | DHCP || |+----------+ | | +----------+|
|| |<-+ | | | Server || || LCS-ISP | (3)| | | DHCP ||
|+----------+ | | | +----------+| || |<-+ | | | Server ||
+-------^------+-+----------------|-----------^--+ |+----------+ | | | +----------+|
+-------|------+-+----------------|-----------|--+ +-------^------+-+----------------|-----------^--+
| IAP | (4) | |(5) | | | +-------|------+-+----------------|-----------|--+
| V | | | | | | IAP | (4) | |(5) | | |
|+----------+ | | | | | | V | | | | |
|| LCS-IAP | | | +--------+ | | | |+----------+ | | | | |
|| | | | | Link | |(6) | | || LCS-IAP | | | +--------+ | | |
|+----------+ | | | Layer | | | | || | | | | Link | |(6) | |
| | | | Device | | (2)| | |+----------+ | | | Layer | | | |
| | | +--------+ | | | | | | | Device | | (2)| |
| | | ^ | | | | | | +--------+ | | |
| | | | | | | | | | ^ | | |
+--------------+-|-------|--------|-----------|--+ | | | | | | |
| | | | | +--------------+-|-------|--------|-----------|--+
| | (1)| | | | | | | |
| | | | | | | (1)| | |
| | | +----+ | | | | | |
| | v | | | | | +----+ |
| | +----------+ | | | v | |
| +->| End |<-------------+ | | +----------+ |
+___>| Host | | +->| End |<-------------+
+----------+ +___>| Host |
+----------+
Figure 2: Architectural Overview Figure 2: Architectural Overview
Note: Figure 2 does not indicate who operates the ESRP and the LoST Note: Figure 2 does not indicate who operates the ESRP and the LoST
server. Various deployment options exist. server. Various deployment options exist.
5.1. End Host Profile 5.1. End Host Profile
5.1.1. LoST Server Discovery 5.1.1. LoST Server Discovery
skipping to change at page 13, line 45 skipping to change at page 10, line 30
mapping SHOULD be performed at the endpoint device. mapping SHOULD be performed at the endpoint device.
End hosts MUST use the Service URN mechanism [RFC5031] to mark calls End hosts MUST use the Service URN mechanism [RFC5031] to mark calls
as emergency calls for their home emergency dial string. as emergency calls for their home emergency dial string.
5.1.5. SIP Emergency Call Signaling 5.1.5. SIP Emergency Call Signaling
SIP signaling capabilities [RFC3261] are mandated for end hosts. SIP signaling capabilities [RFC3261] are mandated for end hosts.
The initial SIP signaling method is an INVITE. The SIP INVITE The initial SIP signaling method is an INVITE. The SIP INVITE
request MUST be constructed according to the requirements in Section request MUST be constructed according to the requirements in
9.2 [I-D.ietf-ecrit-phonebcp]. Section 9.2 [I-D.ietf-ecrit-phonebcp].
Regarding callback behavior SIP UAs SHOULD place a globally routable Regarding callback behavior SIP UAs SHOULD place a globally routable
URI in a Contact: header. URI in a Contact: header.
5.1.6. Media 5.1.6. Media
End points MUST comply with the media requirements for end points End points MUST comply with the media requirements for end points
placing an emergency call found in Section 14 of placing an emergency call found in Section 14 of
[I-D.ietf-ecrit-phonebcp]. [I-D.ietf-ecrit-phonebcp].
skipping to change at page 16, line 28 skipping to change at page 12, line 23
To perform network attachment and get access to the resources To perform network attachment and get access to the resources
provided by an IAP/ISP, the end host uses access technology specific provided by an IAP/ISP, the end host uses access technology specific
network attachment procedures, including for example network network attachment procedures, including for example network
detection and selection, authentication, and authorization. For detection and selection, authentication, and authorization. For
initial network attachment of an emergency service requester, the initial network attachment of an emergency service requester, the
method of how the emergency indication is given to the IAP/ISP is method of how the emergency indication is given to the IAP/ISP is
specific to the access technology. However, a number of general specific to the access technology. However, a number of general
approaches can be identified: approaches can be identified:
Link layer emergency indication: The end host provides an Link layer emergency indication: The end host provides an
indication, e.g. an emergency parameter or flag, as part of the indication, e.g. an emergency parameter or flag, as part of the
link layer signaling for initial network attachment. Examples link layer signaling for initial network attachment. Examples
include an emergency bit signalled in the IEEE 802.16-2009 include an emergency bit signalled in the IEEE 802.16-2009
wireless link. In IEEE 802.11 WLAN, an emergency support wireless link. In IEEE 802.11 WLAN, an emergency support
indicator allows the STA to download before association an NAI indicator allows the STA to download before association an NAI
which it can use to request server side authentication only for an which it can use to request server side authentication only for an
802.1x network. 802.1x network.
Higher-layer emergency indication: Typically emergency indication in Higher-layer emergency indication: Typically emergency indication in
access authentication. The emergency caller's end host provides access authentication. The emergency caller's end host provides
an indication as part of the access authentication exchanges. EAP an indication as part of the access authentication exchanges. EAP
based authentication is of particular relevance here. Examples based authentication is of particular relevance here. Examples
are the EAP NAI decoration used in WiMAX networks and modification are the EAP NAI decoration used in WiMAX networks and modification
of the authentication exchange in IEEE 802.11. [nwgstg3]. of the authentication exchange in IEEE 802.11. [nwgstg3].
6.1. Link Layer Emergency Indication 6.1. Link Layer Emergency Indication
In general, link layer emergency indications provide good integration In general, link layer emergency indications provide good integration
into the actual network access procedure regarding the enabling of into the actual network access procedure regarding the enabling of
means to recognize and prioritize an emergency service request from means to recognize and prioritize an emergency service request from
an end host at a very early stage of the network attachment an end host at a very early stage of the network attachment
procedure. However, support in end hosts for such methods cannot be procedure. However, support in end hosts for such methods cannot be
considered to be commonly available. considered to be commonly available.
skipping to change at page 17, line 33 skipping to change at page 13, line 30
authorization server that owns the policy for granting access to authorization server that owns the policy for granting access to
the network resources. As a result, there is no direct dependency the network resources. As a result, there is no direct dependency
on the access network architecture that otherwise would need to on the access network architecture that otherwise would need to
take care of merging link-layer indications into the AA and policy take care of merging link-layer indications into the AA and policy
decision process. decision process.
o EAP signaling happens at a relatively early stage of network o EAP signaling happens at a relatively early stage of network
attachment, so it is likely to match most requirements for attachment, so it is likely to match most requirements for
prioritization of emergency signaling. However, it does not cover prioritization of emergency signaling. However, it does not cover
early stages of link layer activity in the network attachment early stages of link layer activity in the network attachment
process. Possible conflicts may arise e.g. in case of MAC-based process. Possible conflicts may arise e.g. in case of MAC-based
filtering in entities terminating the link-layer signaling in the filtering in entities terminating the link-layer signaling in the
network (like a base station). In normal operation, EAP related network (like a base station). In normal operation, EAP related
information will only be recognized in the NAS. Any entity information will only be recognized in the NAS. Any entity
residing between end host and NAS should not be expected to residing between end host and NAS should not be expected to
understand/parse EAP messages. understand/parse EAP messages.
o An emergency indication can be given by forming a specific NAI o An emergency indication can be given by forming a specific NAI
that is used as the identity in EAP based authentication for that is used as the identity in EAP based authentication for
network entry. network entry.
skipping to change at page 20, line 24 skipping to change at page 15, line 26
functionality is used for GSM networks today this has lead to a functionality is used for GSM networks today this has lead to a
significant amount of misuse. significant amount of misuse.
In the context of NAA, the IAP and the ISP will probably want to make In the context of NAA, the IAP and the ISP will probably want to make
sure that the claimed emergency caller indeed performs an emergency sure that the claimed emergency caller indeed performs an emergency
call rather than using the network for other purposes, and thereby call rather than using the network for other purposes, and thereby
acting fraudulent by skipping any authentication, authorization and acting fraudulent by skipping any authentication, authorization and
accounting procedures. By restricting access of the unauthenticated accounting procedures. By restricting access of the unauthenticated
emergency caller to the LoST server and the PSAP URI, traffic can be emergency caller to the LoST server and the PSAP URI, traffic can be
restricted only to emergency calls. This can be accomplished with restricted only to emergency calls. This can be accomplished with
traffic separation. The details, however, e.g. for using filtering, traffic separation. The details, however, e.g. for using filtering,
depend on the deployed ISP architecture and are beyond the scope of depend on the deployed ISP architecture and are beyond the scope of
this document. this document.
We only illustrate a possible model. If the ISP runs its own LoST We only illustrate a possible model. If the ISP runs its own LoST
server, it would maintain an access control list including all IP server, it would maintain an access control list including all IP
addresses contained in responses returned by the LoST server, as well addresses contained in responses returned by the LoST server, as well
as the LoST server itself. (It may need to translate the domain as the LoST server itself. (It may need to translate the domain
names returned to IP addresses and hope that the resolution captures names returned to IP addresses and hope that the resolution captures
all possible DNS responses.) Since the media destination addresses all possible DNS responses.) Since the media destination addresses
are not predictable, the ISP also has to provide a SIP outbound proxy are not predictable, the ISP also has to provide a SIP outbound proxy
skipping to change at page 23, line 36 skipping to change at page 17, line 11
A., Peterson, J., Sparks, R., Handley, M., and E. A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", RFC 3261, Schooler, "SIP: Session Initiation Protocol", RFC 3261,
June 2002. June 2002.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[I-D.ietf-ecrit-phonebcp] [I-D.ietf-ecrit-phonebcp]
Rosen, B. and J. Polk, "Best Current Practice for Rosen, B. and J. Polk, "Best Current Practice for
Communications Services in support of Emergency Calling", Communications Services in support of Emergency Calling",
draft-ietf-ecrit-phonebcp-20 (work in progress), draft-ietf-ecrit-phonebcp-20 (work in progress), September
September 2011. 2011.
[RFC5222] Hardie, T., Newton, A., Schulzrinne, H., and H. [RFC5222] Hardie, T., Newton, A., Schulzrinne, H., and H.
Tschofenig, "LoST: A Location-to-Service Translation Tschofenig, "LoST: A Location-to-Service Translation
Protocol", RFC 5222, August 2008. Protocol", RFC 5222, August 2008.
[RFC5223] Schulzrinne, H., Polk, J., and H. Tschofenig, "Discovering [RFC5223] Schulzrinne, H., Polk, J., and H. Tschofenig, "Discovering
Location-to-Service Translation (LoST) Servers Using the Location-to-Service Translation (LoST) Servers Using the
Dynamic Host Configuration Protocol (DHCP)", RFC 5223, Dynamic Host Configuration Protocol (DHCP)", RFC 5223,
August 2008. August 2008.
skipping to change at page 24, line 11 skipping to change at page 17, line 35
[RFC5687] Tschofenig, H. and H. Schulzrinne, "GEOPRIV Layer 7 [RFC5687] Tschofenig, H. and H. Schulzrinne, "GEOPRIV Layer 7
Location Configuration Protocol: Problem Statement and Location Configuration Protocol: Problem Statement and
Requirements", RFC 5687, March 2010. Requirements", RFC 5687, March 2010.
[RFC6443] Rosen, B., Schulzrinne, H., Polk, J., and A. Newton, [RFC6443] Rosen, B., Schulzrinne, H., Polk, J., and A. Newton,
"Framework for Emergency Calling Using Internet "Framework for Emergency Calling Using Internet
Multimedia", RFC 6443, December 2011. Multimedia", RFC 6443, December 2011.
[I-D.ietf-geopriv-res-gw-lis-discovery] [I-D.ietf-geopriv-res-gw-lis-discovery]
Thomson, M. and R. Bellis, "Location Information Server Thomson, M. and R. Bellis, "Location Information Server
(LIS) Discovery using IP address and Reverse DNS", (LIS) Discovery using IP address and Reverse DNS", draft-
draft-ietf-geopriv-res-gw-lis-discovery-02 (work in ietf-geopriv-res-gw-lis-discovery-05 (work in progress),
progress), September 2011. April 2013.
[RFC5985] Barnes, M., "HTTP-Enabled Location Delivery (HELD)", [RFC5985] Barnes, M., "HTTP-Enabled Location Delivery (HELD)", RFC
RFC 5985, September 2010. 5985, September 2010.
[RFC5012] Schulzrinne, H. and R. Marshall, "Requirements for [RFC5012] Schulzrinne, H. and R. Marshall, "Requirements for
Emergency Context Resolution with Internet Technologies", Emergency Context Resolution with Internet Technologies",
RFC 5012, January 2008. RFC 5012, January 2008.
[RFC6444] Schulzrinne, H., Liess, L., Tschofenig, H., Stark, B., and [RFC6444] Schulzrinne, H., Liess, L., Tschofenig, H., Stark, B., and
A. Kuett, "Location Hiding: Problem Statement and A. Kuett, "Location Hiding: Problem Statement and
Requirements", RFC 6444, January 2012. Requirements", RFC 6444, January 2012.
[I-D.winterbottom-geopriv-lis2lis-req] [I-D.winterbottom-geopriv-lis2lis-req]
Winterbottom, J. and S. Norreys, "LIS to LIS Protocol Winterbottom, J. and S. Norreys, "LIS to LIS Protocol
Requirements", draft-winterbottom-geopriv-lis2lis-req-01 Requirements", draft-winterbottom-geopriv-lis2lis-req-01
(work in progress), November 2007. (work in progress), November 2007.
[RFC5069] Taylor, T., Tschofenig, H., Schulzrinne, H., and M. [RFC5069] Taylor, T., Tschofenig, H., Schulzrinne, H., and M.
Shanmugam, "Security Threats and Requirements for Shanmugam, "Security Threats and Requirements for
Emergency Call Marking and Mapping", RFC 5069, Emergency Call Marking and Mapping", RFC 5069, January
January 2008. 2008.
[RFC6280] Barnes, R., Lepinski, M., Cooper, A., Morris, J., [RFC6280] Barnes, R., Lepinski, M., Cooper, A., Morris, J.,
Tschofenig, H., and H. Schulzrinne, "An Architecture for Tschofenig, H., and H. Schulzrinne, "An Architecture for
Location and Location Privacy in Internet Applications", Location and Location Privacy in Internet Applications",
BCP 160, RFC 6280, July 2011. BCP 160, RFC 6280, July 2011.
[esw07] "3rd SDO Emergency Services Workshop, [esw07] , "3rd SDO Emergency Services Workshop,
http://www.emergency-services-coordination.info/2007Nov/", http://www.emergency-services-coordination.info/2007Nov/",
October 30th - November 1st 2007. October 30th - November 1st 2007.
[nwgstg3] "WiMAX Forum WMF-T33-001-R015V01, WiMAX Network [nwgstg3] , "WiMAX Forum WMF-T33-001-R015V01, WiMAX Network
Architecture Stage-3 Architecture Stage-3
http://www.wimaxforum.org/sites/wimaxforum.org/files/ tech http://www.wimaxforum.org/sites/wimaxforum.org/files/
nical_document/2009/09/ technical_document/2009/09/DRAFT-T33-001-R015v01
DRAFT-T33-001-R015v01-O_Network-Stage3-Base.pdf", -O_Network-Stage3-Base.pdf", September 2009.
September 2009.
Authors' Addresses Authors' Addresses
Henning Schulzrinne Henning Schulzrinne
Columbia University Columbia University
Department of Computer Science Department of Computer Science
450 Computer Science Building 450 Computer Science Building
New York, NY 10027 New York, NY 10027
US US
skipping to change at page 26, line 4 skipping to change at page 19, line 18
Hannes Tschofenig Hannes Tschofenig
Nokia Siemens Networks Nokia Siemens Networks
Linnoitustie 6 Linnoitustie 6
Espoo 02600 Espoo 02600
Finland Finland
Phone: +358 (50) 4871445 Phone: +358 (50) 4871445
Email: Hannes.Tschofenig@gmx.net Email: Hannes.Tschofenig@gmx.net
URI: http://www.tschofenig.priv.at URI: http://www.tschofenig.priv.at
Dirk Kroeselberg Dirk Kroeselberg
Siemens Siemens
Germany Germany
Phone:
Email: dirk.kroeselberg@siemens.com Email: dirk.kroeselberg@siemens.com
 End of changes. 23 change blocks. 
104 lines changed or deleted 104 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/