draft-ietf-roll-capabilities-05.txt   draft-ietf-roll-capabilities-06.txt 
ROLL R. Jadhav, Ed. ROLL R. Jadhav, Ed.
Internet-Draft Huawei Internet-Draft Huawei
Intended status: Standards Track P. Thubert Intended status: Standards Track P. Thubert
Expires: November 22, 2020 Cisco Expires: December 5, 2020 Cisco
M. Richardson M. Richardson
Sandelman Software Works Sandelman Software Works
R. Sahoo R. Sahoo
Juniper Juniper
May 21, 2020 June 3, 2020
RPL Capabilities RPL Capabilities
draft-ietf-roll-capabilities-05 draft-ietf-roll-capabilities-06
Abstract Abstract
This draft enables the discovery, advertisement and query of This draft enables the discovery, advertisement and query of
capabilities for RPL nodes. capabilities for RPL nodes.
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.
skipping to change at page 1, line 36 skipping to change at page 1, line 36
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 https://datatracker.ietf.org/drafts/current/. Drafts is at https://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 November 22, 2020. This Internet-Draft will expire on December 5, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language and Terminology . . . . . . . . . . 3 1.1. Requirements Language and Terminology . . . . . . . . . . 3
1.2. What are Capabilities? . . . . . . . . . . . . . . . . . 3 1.2. What are Capabilities? . . . . . . . . . . . . . . . . . 4
2. Requirements for this document . . . . . . . . . . . . . . . 4 2. Requirements for this document . . . . . . . . . . . . . . . 4
2.1. How are Capabilities different from existing RPL 2.1. How are Capabilities different from existing RPL
primitives? . . . . . . . . . . . . . . . . . . . . . . . 4 primitives? . . . . . . . . . . . . . . . . . . . . . . . 4
3. Capabilities . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Capabilities . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Capability Control Message Option . . . . . . . . . . . . 5 3.1. Capability Control Message Option . . . . . . . . . . . . 5
3.2. Capabilities Handshake . . . . . . . . . . . . . . . . . 5 3.2. Capabilities Handshake . . . . . . . . . . . . . . . . . 6
4. Guidelines for defining new capabilities . . . . . . . . . . 6 4. Querying Capabilities . . . . . . . . . . . . . . . . . . . . 6
4.1. Handling Capability flags . . . . . . . . . . . . . . . . 6 4.1. Capability Query (CAPQ) . . . . . . . . . . . . . . . . . 6
4.1.1. Rules to handle capabilities flag . . . . . . . . . . 6 4.1.1. Capability Type List Control Option . . . . . . . . . 7
5. Node Capabilities . . . . . . . . . . . . . . . . . . . . . . 6 4.1.2. Secure CAPQ . . . . . . . . . . . . . . . . . . . . . 7
5.1. Capability Indicators . . . . . . . . . . . . . . . . . . 7 4.1.3. Base rules for CAPQ handling . . . . . . . . . . . . 7
5.1.1. Format of Capability Indicators . . . . . . . . . . . 7 4.2. Capability Set Response (CAPS) . . . . . . . . . . . . . 7
5.2. Routing Resource Capability . . . . . . . . . . . . . . . 7 4.2.1. Secure CAPS . . . . . . . . . . . . . . . . . . . . . 8
5.2.1. Format of Routing Resource Capability . . . . . . . . 8 5. Guidelines for defining new capabilities . . . . . . . . . . 8
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 5.1. Handling Capability flags . . . . . . . . . . . . . . . . 8
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 5.1.1. Rules to handle capabilities flag . . . . . . . . . . 9
7.1. New option: Capabilities . . . . . . . . . . . . . . . . 8 6. Node Capabilities . . . . . . . . . . . . . . . . . . . . . . 9
7.2. New Registry for Capabilities Flags . . . . . . . . . . . 9 6.1. Capability Indicators . . . . . . . . . . . . . . . . . . 9
7.3. New Registry for Capabilities Indicators . . . . . . . . 9 6.1.1. Format of Capability Indicators . . . . . . . . . . . 9
8. Security Considerations . . . . . . . . . . . . . . . . . . . 9 6.2. Routing Resource Capability . . . . . . . . . . . . . . . 9
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 6.2.1. Format of Routing Resource Capability . . . . . . . . 10
9.1. Normative References . . . . . . . . . . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
9.2. Informative References . . . . . . . . . . . . . . . . . 10 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
Appendix A. Capability Handshake Example . . . . . . . . . . . . 11 8.1. New option: Capabilities . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 8.2. Capability Sub-Type . . . . . . . . . . . . . . . . . . . 11
8.3. New Registry for CAPQ Flags . . . . . . . . . . . . . . . 12
8.4. New Registry for Capabilities Flags . . . . . . . . . . . 12
8.5. New Registry for Capabilities Indicators . . . . . . . . 12
9. Security Considerations . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . 13
Appendix A. Capability Handshake Example . . . . . . . . . . . . 14
A.1. Query supported Cap Types . . . . . . . . . . . . . . . . 14
A.2. Query specific Cap Set . . . . . . . . . . . . . . . . . 14
A.3. CAPS with partial Cap Set . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction 1. Introduction
RPL [RFC6550] specifies a proactive distance-vector based routing RPL [RFC6550] specifies a proactive distance-vector based routing
scheme. The protocol creates a DAG-like structure which operates scheme. The protocol creates a DAG-like structure which operates
with a given "Mode of Operation" (MOP) determining the minimal and with a given "Mode of Operation" (MOP) determining the minimal and
mandatory set of primitives to be supported by all the participating mandatory set of primitives to be supported by all the participating
nodes. nodes.
This document adds a notion of capabilities using which nodes in the This document adds a notion of capabilities using which nodes in the
skipping to change at page 3, line 19 skipping to change at page 3, line 32
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
MOP: Mode of Operation. Identifies the MOP of the RPL Instance as MOP: Mode of Operation. Identifies the MOP of the RPL Instance as
administratively provisioned at and distributed by the DODAG root. administratively provisioned at and distributed by the DODAG root.
MOPex: Extended MOP: As defined in [I-D.ietf-roll-mopex]. MOPex: Extended MOP: As defined in [I-D.ietf-roll-mopex].
Capabilities: Additional features or capabilities that are supported Capabilities: Additional features or capabilities that are supported
by the node. by the node.
Cap: Abbreviated term used for Capability.
Caps: Abbreviated term used for Capabilities.
DAO: DODAG Advertisement Object. An RPL message used to advertise DAO: DODAG Advertisement Object. An RPL message used to advertise
the target information in order to establish routing adjacencies. the target information in order to establish routing adjacencies.
DIO: DODAG Information Object. An RPL message initiated by the root DIO: DODAG Information Object. An RPL message initiated by the root
and is used to advertise the network configuration information. and is used to advertise the network configuration information.
Current parent: Parent 6LR node before switching to the new path. Current parent: Parent 6LR node before switching to the new path.
NPDAO: No-Path DAO. A DAO message which has target with lifetime 0. NPDAO: No-Path DAO. A DAO message which has target with lifetime 0.
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section. section.
1.2. What are Capabilities? 1.2. What are Capabilities?
Currently RPL specification does not have a mechanism whereby a node Currently RPL specification does not have a mechanism whereby a node
can signal the set of features that are available on its end. Such a can signal the set of features that are available on its end. Such a
mechanism could help the root to advertise its capabilities and in mechanism could help the root to advertise its capabilities and in
response also determine some advanced information about the response also determine some advanced information about the
capabilities of the joining nodes. This document defines capabilities of the joining nodes. This document defines
Capabilities which could be supported by the nodes and handshaked as Capabilities which could be supported by the nodes and handshaked as
part of RPL signaling. Capabilities are embedded as RPL control part of RPL signaling. Capabilities are embedded as an RPL Control
message option as defined Section 6.7 of [RFC6550] in the base Message Option as defined in Section 6.7 of [RFC6550].
messages of DIO, DAO and DAO-ACK signaling.
2. Requirements for this document 2. Requirements for this document
Following are the requirements considered for this documents: Following are the requirements considered for this documents:
REQ1: Backwards compatibility. The new options and new fields in REQ1: Backwards compatibility. The new options and new fields in
the DIO message should be backward compatible i.e. if there the DIO message should be backward compatible i.e. if there
are nodes which support old MOPs they could still operate in are nodes which support old MOPs they could still operate in
their own instances. their own instances.
skipping to change at page 6, line 12 skipping to change at page 6, line 25
advertised by non-root nodes are strictly a subset of the advertised by non-root nodes are strictly a subset of the
capabilities advertised by the root. capabilities advertised by the root.
In storing MOP, the DAO message from the 6LR could contain multiple In storing MOP, the DAO message from the 6LR could contain multiple
target options because of the DAO-Aggregation. The targets of the target options because of the DAO-Aggregation. The targets of the
capabilities option are indicated by one or more Target options that capabilities option are indicated by one or more Target options that
precede the Capabilities Option. This handling is similar to the precede the Capabilities Option. This handling is similar to the
Transit Information Option as supported in Section 6.7.8. of Transit Information Option as supported in Section 6.7.8. of
[RFC6550]. [RFC6550].
4. Guidelines for defining new capabilities 4. Querying Capabilities
Nodes may be interested in knowing the capabilities of another node
before taking an action. For e.g., Consider
[I-D.ietf-roll-dao-projection], the Root may want to know the
capabilities of the nodes along a network segment before it initiates
a projected DAO to install the routes along that segment.
Caps can be carried in existing RPL Control messages as Control
Options, however Caps can also be queried explicitly. This section
provides a way for a node to query capability set of another node.
The capability query and subsequent response messages are directly
addressed between the two peers.
4.1. Capability Query (CAPQ)
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RPLInstanceID | Flags | reserved | CAPQSequence |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option(s)...
+-+-+-+-+-+-+-+-+
Figure 3: CAPQ base object
CAPQSequence: One byte, Sequence number sent by the CAPQ sender
which is reflected back by the responder in the CAPS message.
Flags: One byte, set to zero by sender, ignored by receiver.
reserved: One byte, set to zero by sender, ignored by receiver.
CAPQ base object may be followed by one or more options. The
Capability Type List Control Option Figure 4 is used to carry a set
of capability types to query about.
If the sender does not send Figure 4 option, this would indicate that
the node intends to query the capability type list Figure 4 supported
by the target node.
4.1.1. Capability Type List Control Option
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = TODO | Option Length | CapType1 | CapType2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CapType3 | .....
+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Capability Type List Control Option
4.1.2. Secure CAPQ
A Secure CAPQ message follows the format in [RFC6550] Figure 7, where
the base message format is the CAPQ message shown in Figure 3.
4.1.3. Base rules for CAPQ handling
A CAPQ message may get dropped or lost in the transit. The sender of
CAPQ MAY retry the CAPQ message after some delay. The delay SHOULD
NOT be less than 1 second.
4.2. Capability Set Response (CAPS)
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RPLInstanceID | Flags | Reserved | CAPQSequence |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option(s)...
+-+-+-+-+-+-+-+-+
Figure 5: CAPS base object
Flags: One byte, set to zero by sender, ignored by receiver.
reserved: One byte, set to zero by sender, ignored by receiver.
CAPQSequence: One byte, Sequence number copied from CAPQSequence
received in the CAPQ message.
CAPS message SHOULD contain the capability set Figure 1 queried by
the CAPQ sender. If the target node does not support subset of the
queried capabilities then the Figure 4 option with the unsupported
cap-types SHOULD be sent back indicating the queried capabilities
not-supported by the target node. For an example, check Appendix A.3
If the CAPQ message does not contain any Figure 4 option then the
receiver MUST respond with the cap types it supports using Figure 4.
If the capability set cannot be transmitted in a single message (for
e.g., because of MTU limitations) then multiple CAPS messages could
be used. All the CAPS message MUST use the same CAPQSequence number
copied from the corresponding CAPQ message.
4.2.1. Secure CAPS
A Secure CAPS message follows the format in [RFC6550] Figure 7, where
the base message format is the CAPS message shown in Figure 5.
5. Guidelines for defining new capabilities
This section provides guidelines/recommendations towards defining new This section provides guidelines/recommendations towards defining new
capabilities. Note that the capabilities might be carried as part of capabilities. Note that the capabilities might be carried as part of
the multicast messaging such as DIO and hence the set should be used the multicast messaging such as DIO and hence the set should be used
in restrictive manner as far as possible. in restrictive manner as far as possible.
4.1. Handling Capability flags 5.1. Handling Capability flags
A node MUST drop or discard the message with an unknown capability A node MUST drop or discard the message with an unknown capability
with 'D' flag set. The message MUST be discarded silently. with 'D' flag set. The message MUST be discarded silently.
The 'J' (join) flag can be set in context to a capability either by a The 'J' (join) flag can be set in context to a capability either by a
6LR or the root. The 'J' flag indicates that if the capability is 6LR or the root. The 'J' flag indicates that if the capability is
not supported by a node then it can join the instance only as a 6LN not supported by a node then it can join the instance only as a 6LN
(or do not join as 6LR). (or do not join as 6LR).
The 'C' (copy) flag is set by the node indicating that the The 'C' (copy) flag is set by the node indicating that the
capabilities MUST be copied downstream by the node even if the node capabilities MUST be copied downstream by the node even if the node
does not understand the capability. does not understand the capability.
4.1.1. Rules to handle capabilities flag 5.1.1. Rules to handle capabilities flag
On receiving a capability it does not support, the node MUST check On receiving a capability it does not support, the node MUST check
the 'J' flag of the capability before joining the Instance. If the the 'J' flag of the capability before joining the Instance. If the
'J' flag is set then it can only join as a 6LN. 'J' flag is set then it can only join as a 6LN.
If the node is operating as 6LR and subsequently it receives a If the node is operating as 6LR and subsequently it receives a
capability from its preferred parent which it does not understand capability from its preferred parent which it does not understand
with 'J' flag set, then the node has to switch itself to 6LN mode. with 'J' flag set, then the node has to switch itself to 6LN mode.
During switching the node needs to inform its downstream peers of its During switching the node needs to inform its downstream peers of its
changed status by sending a DIO with infinite rank as mentioned in changed status by sending a DIO with infinite rank as mentioned in
RFC6550. Alternatively, a node may decide to switch to another RFC6550. Alternatively, a node may decide to switch to another
parent with compatible and known capabilities. parent with compatible and known capabilities.
Capabilities are used to indicate a feature that is supported by the Capabilities are used to indicate a feature that is supported by the
node. Capabilities are not meant for configuration management for node. Capabilities are not meant for configuration management for
e.g., setting a threshold. e.g., setting a threshold.
5. Node Capabilities 6. Node Capabilities
5.1. Capability Indicators
6.1. Capability Indicators
Capability Indicators indicates the capabilities supported by the Capability Indicators indicates the capabilities supported by the
node in the form of simple flags. Capabilities who do not have node in the form of simple flags. Capabilities who do not have
additional information to be specified could make use of these flags additional information to be specified could make use of these flags
to indicate their support. to indicate their support.
5.1.1. Format of Capability Indicators 6.1.1. Format of Capability Indicators
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CapType=0x01 | Len |J|I|C| Flags |T|..Indicators.. | CapType=0x01 | Len |J|I|C| Flags |T|..Indicators..
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Capability Indicators TLV Figure 6: Capability Indicators TLV
Flags: LRs MUST set it to 0. I bit will always be set to 0. Flags: LRs MUST set it to 0. I bit will always be set to 0.
T flag (Bit 1): Indicates whether the node supports 6LoRH [RFC8138]. T flag (Bit 1): Indicates whether the node supports 6LoRH [RFC8138].
5.2. Routing Resource Capability 6.2. Routing Resource Capability
Storing mode of operation requires each intermediate router in the Storing mode of operation requires each intermediate router in the
LLN to maintain routing states' information in the routing table. LLN to maintain routing states' information in the routing table.
LLN routers typically operate with constraints on processing power, LLN routers typically operate with constraints on processing power,
memory, and energy (battery power). Memory limits the number of memory, and energy (battery power). Memory limits the number of
routing states an LR and BR can maintain. When the routing table of routing states an LR and BR can maintain. When the routing table of
an LR or BR is full, it will either reject the new DAO messages an LR or BR is full, it will either reject the new DAO messages
received or will use some replacement policy to remove a routing received or will use some replacement policy to remove a routing
entry and add the new one. Rejection of DAO messages will lead to an entry and add the new one. Rejection of DAO messages will lead to an
increase in DAO message transmission that impacts the energy and increase in DAO message transmission that impacts the energy and
skipping to change at page 8, line 5 skipping to change at page 10, line 21
advertise their current routing table usage details in the network. advertise their current routing table usage details in the network.
LR or LNs in LLN can use this information in the selection of the DAO LR or LNs in LLN can use this information in the selection of the DAO
parent set. PCE can use this information to select intermediate parent set. PCE can use this information to select intermediate
routers for the projected routes. Routing Resource is an optional routers for the projected routes. Routing Resource is an optional
capability. capability.
Routing resource capabablity sent in DIO message has link local scope Routing resource capabablity sent in DIO message has link local scope
and it MUST not be forwarded. The 'C' bit of this capability MUST be and it MUST not be forwarded. The 'C' bit of this capability MUST be
set to 0. set to 0.
5.2.1. Format of Routing Resource Capability 6.2.1. Format of Routing Resource Capability
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CapType=0x02 | Len=3 |J|I|C| Flags | Reserved | | CapType=0x02 | Len=3 |J|I|C| Flags | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Total Capacity | | Total Capacity |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Routing Resource Capability TLV Figure 7: Routing Resource Capability TLV
Type: 0x02. Type: 0x02.
Flags: I bit MUST be set to 0. C bit MUST be set to 0. Flags: I bit MUST be set to 0. C bit MUST be set to 0.
Len: 8-bit unsigned integer, representing the length in octets of the Len: 8-bit unsigned integer, representing the length in octets of the
option, not including the Option Type and Length/flags fields. option, not including the Option Type and Length/flags fields.
Resvd: 8-bit unused field. It MUST be initialized to zero by the Resvd: 8-bit unused field. It MUST be initialized to zero by the
sender and MUST be ignored by the receiver. sender and MUST be ignored by the receiver.
Total Capacity: 16 bit unsigned integer representing the routing Total Capacity: 16 bit unsigned integer representing the routing
table size. table size.
6. Acknowledgements 7. Acknowledgements
Thanks to Georgios Papadopoulos, Li Zhao for early review and Thanks to Georgios Papadopoulos, Li Zhao for early review and
feedback. feedback.
7. IANA Considerations 8. IANA Considerations
7.1. New option: Capabilities IANA is requested to allocate new codes for the CAPQ and CAPS
messages from the RPL Control Codes registry.
New entry is required for supporting new Capabilities option in the +------+----------------------------+---------------+
"RPL Control Message Options" space [RFC6550]. | Code | Description | Reference |
+------+----------------------------+---------------+
| TBD1 | Capability Query | This document |
| TBD2 | Capability Response | This document |
| TBD3 | Secure Capability Query | This document |
| TBD4 | Secure Capability Response | This document |
+------+----------------------------+---------------+
New RPL Control Messages
The MSB of the codes allocated to "Secure" messages above should be
set.
8.1. New option: Capabilities
New entry is required for supporting new Capabilities option and new
Capability Type List Option in the "RPL Control Message Options"
space [RFC6550].
+-------+-----------------------------+---------------+
| Value | Meaning | Reference |
+-------+-----------------------------+---------------+
| TODO | Capability Option | This document |
| TODO | Capability Type List Option | This document |
+-------+-----------------------------+---------------+
New options
8.2. Capability Sub-Type
IANA is requested to create a registry for the Capabilities Type as
described in Figure 2 of this document. This registry should be
located in TODO. New Capabilities types may be allocated only by an
IETF review.
+-------+-----------------------------+---------------+ +-------+-----------------------------+---------------+
| Value | Meaning | Reference | | Value | Meaning | Reference |
+-------+-----------------------------+---------------+ +-------+-----------------------------+---------------+
| 0x01 | Capability Indicators | This document | | 0x01 | Capability Indicators | This document |
| 0x02 | Routing Resource Capability | This document | | 0x02 | Routing Resource Capability | This document |
+-------+-----------------------------+---------------+ +-------+-----------------------------+---------------+
New options Type
7.2. New Registry for Capabilities Flags 8.3. New Registry for CAPQ Flags
IANA is requested to create a registry for the Capabilities flags as
described in Section 4.1 of this document. This registry should be
located in TODO. New Capabilities flags may be allocated only by an
IETF review. Currently no flags are defined by this document. Each
value is tracked with the following qualities:
o Flag
o Description
o Defining RFC
8.4. New Registry for Capabilities Flags
IANA is requested to create a registry for the Capabilities flags as IANA is requested to create a registry for the Capabilities flags as
described in Section 2.1 of this document. This registry should be described in Section 2.1 of this document. This registry should be
located in TODO. New Capabilities flags may be allocated only by an located in TODO. New Capabilities flags may be allocated only by an
IETF review. Currently no flags are defined by this document. Each IETF review. Currently no flags are defined by this document. Each
value is tracked with the following qualities: value is tracked with the following qualities:
o Flag o Flag
o Description o Description
o Defining RFC o Defining RFC
7.3. New Registry for Capabilities Indicators 8.5. New Registry for Capabilities Indicators
IANA is requested to create a registry for the Capabilities IANA is requested to create a registry for the Capabilities
Indicators as described in Section 5.1 of this document. This Indicators as described in Section 6.1 of this document. This
registry should be located in TODO. New Capabilities indicators may registry should be located in TODO. New Capabilities indicators may
be allocated only by an IETF review. Each value is tracked with the be allocated only by an IETF review. Each value is tracked with the
following qualities: following qualities:
o Flag o Flag
o Description o Description
o Defining RFC o Defining RFC
8. Security Considerations 9. Security Considerations
The options defined in this document are carried in the base message The options defined in this document are carried in the base message
objects as defined in [RFC6550]. The RPL control message options are objects as defined in [RFC6550]. The RPL control message options are
protected by the same security mechanisms that protect the base protected by the same security mechanisms that protect the base
messages. messages.
Capabilities flag can reveal that the node has been upgraded or is Capabilities flag can reveal that the node has been upgraded or is
running a old feature set. This document assumes that the base running a old feature set. This document assumes that the base
messages that carry these options are protected by RPL security messages that carry these options are protected by RPL security
mechanisms and thus are not visible to a malicious node. mechanisms and thus are not visible to a malicious node.
[TODO] implications of malicious attack involving setting the [TODO] implications of malicious attack involving setting the
capability flags. capability flags.
9. References 10. References
9.1. Normative References
10.1. Normative References
[I-D.ietf-roll-mopex] [I-D.ietf-roll-mopex]
Jadhav, R., Thubert, P., and M. Richardson, "Mode of Jadhav, R., Thubert, P., and M. Richardson, "Mode of
Operation extension", draft-ietf-roll-mopex-00 (work in Operation extension", draft-ietf-roll-mopex-00 (work in
progress), April 2020. progress), April 2020.
[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, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
skipping to change at page 10, line 28 skipping to change at page 13, line 47
JP., and R. Alexander, "RPL: IPv6 Routing Protocol for JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
Low-Power and Lossy Networks", RFC 6550, Low-Power and Lossy Networks", RFC 6550,
DOI 10.17487/RFC6550, March 2012, DOI 10.17487/RFC6550, March 2012,
<https://www.rfc-editor.org/info/rfc6550>. <https://www.rfc-editor.org/info/rfc6550>.
[RFC8138] Thubert, P., Ed., Bormann, C., Toutain, L., and R. Cragie, [RFC8138] Thubert, P., Ed., Bormann, C., Toutain, L., and R. Cragie,
"IPv6 over Low-Power Wireless Personal Area Network "IPv6 over Low-Power Wireless Personal Area Network
(6LoWPAN) Routing Header", RFC 8138, DOI 10.17487/RFC8138, (6LoWPAN) Routing Header", RFC 8138, DOI 10.17487/RFC8138,
April 2017, <https://www.rfc-editor.org/info/rfc8138>. April 2017, <https://www.rfc-editor.org/info/rfc8138>.
9.2. Informative References 10.2. Informative References
[I-D.ietf-lwig-nbr-mgmt-policy] [I-D.ietf-lwig-nbr-mgmt-policy]
Jadhav, R., Sahoo, R., Duquennoy, S., and J. Eriksson, Jadhav, R., Sahoo, R., Duquennoy, S., and J. Eriksson,
"Neighbor Management Policy for 6LoWPAN", draft-ietf-lwig- "Neighbor Management Policy for 6LoWPAN", draft-ietf-lwig-
nbr-mgmt-policy-03 (work in progress), February 2019. nbr-mgmt-policy-03 (work in progress), February 2019.
[I-D.ietf-roll-dao-projection] [I-D.ietf-roll-dao-projection]
Thubert, P., Jadhav, R., and M. Gillmore, "Root initiated Thubert, P., Jadhav, R., and M. Gillmore, "Root initiated
routing state in RPL", draft-ietf-roll-dao-projection-10 routing state in RPL", draft-ietf-roll-dao-projection-10
(work in progress), May 2020. (work in progress), May 2020.
skipping to change at page 11, line 7 skipping to change at page 14, line 28
progress), July 2019. progress), July 2019.
[RFC6551] Vasseur, JP., Ed., Kim, M., Ed., Pister, K., Dejean, N., [RFC6551] Vasseur, JP., Ed., Kim, M., Ed., Pister, K., Dejean, N.,
and D. Barthel, "Routing Metrics Used for Path Calculation and D. Barthel, "Routing Metrics Used for Path Calculation
in Low-Power and Lossy Networks", RFC 6551, in Low-Power and Lossy Networks", RFC 6551,
DOI 10.17487/RFC6551, March 2012, DOI 10.17487/RFC6551, March 2012,
<https://www.rfc-editor.org/info/rfc6551>. <https://www.rfc-editor.org/info/rfc6551>.
Appendix A. Capability Handshake Example Appendix A. Capability Handshake Example
Root 6LR 6LN A.1. Query supported Cap Types
| | |
| DIO(CS1) | |
|------------>| DIO(CS1) |
| |----------->|
| | |
| | DAO(CS2) |
| |<-----------|
| DAO(CS2) | |
|<------------| |
| | |
CS: Capabilities Set
CS1: Capabilities set advertised by root
CS2: Capabilities set advertised by node. CS2 is a subset of CS1.
Figure 5: Capabilities Option Root 6LR/6LN
| |
| CAPQ(seq=1, opts=nil) |
|---------------------------------->|
| |
| |
| CAPS(seq=1, opts={CapTypeList}) |
|<----------------------------------|
| |
Figure 8: Query supported Cap Types
CAPQ message with no CapTypeList Option results in the peer
responding with a CAPS message with CapTypeList Option indicating all
the capability set it supports.
A.2. Query specific Cap Set
Root 6LR/6LN
| |
| CAPQ(seq=2, |
| opts={CapTypeList=[Cap1, Cap2]})|
|---------------------------------->|
| |
| |
| CAPS(seq=2, |
| opts={Cap1=Cap1Value, |
| Cap2=Cap2Value}) |
|<----------------------------------|
| |
Figure 9: Query specific Cap Set
This flow indicates the case where the Root probes for specific
Capabilities of the peer node and the peer node responds with the
value of indicated Capability set.
A.3. CAPS with partial Cap Set
Root 6LR/6LN
| |
| CAPQ(seq=3, |
| opts={CapTypeList=[Cap1, Cap2, |
| Cap3, Cap4]})|
|---------------------------------->|
| |
| |
| CAPS(seq=3, |
| opts={Cap2=Cap2Value, |
| Cap3=Cap3Value, |
| CapTypeList=[Cap1,Cap4]})|
|<----------------------------------|
| |
Partial Capability Set handshake
Assume that Root queries for capabilities {Cap1, Cap2, Cap3, Cap4}
from the peer node. However the peer node does not support or does
not understand capability {cap1, cap4}. In this case the peer node
will respond back with value of Cap2 and Cap3 (which it understands)
and set the CapTypeList option with {Cap1, Cap4} type.
Authors' Addresses Authors' Addresses
Rahul Arvind Jadhav (editor) Rahul Arvind Jadhav (editor)
Huawei Huawei
Kundalahalli Village, Whitefield, Kundalahalli Village, Whitefield,
Bangalore, Karnataka 560037 Bangalore, Karnataka 560037
India India
Phone: +91-080-49160700 Phone: +91-080-49160700
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