draft-ietf-teas-mpls-tp-rsvpte-ext-associated-lsp-07.txt   rfc7551.txt 
TEAS Working Group Fei Zhang, Ed. Internet Engineering Task Force (IETF) F. Zhang, Ed.
Internet-Draft Huawei Request for Comments: 7551 Huawei
Intended status: Standards Track Ruiquan Jing Category: Standards Track R. Jing
Expires: September 4, 2015 China Telecom ISSN: 2070-1721 China Telecom
Rakesh Gandhi, Ed. R. Gandhi, Ed.
Cisco Systems Cisco Systems
March 3, 2015 May 2015
RSVP-TE Extensions for Associated Bidirectional LSPs RSVP-TE Extensions
draft-ietf-teas-mpls-tp-rsvpte-ext-associated-lsp-07 for Associated Bidirectional Label Switched Paths (LSPs)
Abstract Abstract
This document describes Resource reSerVation Protocol (RSVP) This document describes Resource Reservation Protocol (RSVP)
extensions to bind two point-to-point unidirectional Label Switched extensions to bind two point-to-point unidirectional Label Switched
Paths (LSPs) into an associated bidirectional LSP. The association Paths (LSPs) into an associated bidirectional LSP. The association
is achieved by defining new Association Types for use in ASSOCIATION is achieved by defining new Association Types for use in ASSOCIATION
and in Extended ASSOCIATION Objects. One of these types enables and in Extended ASSOCIATION Objects. One of these types enables
independent provisioning of the associated bidirectional LSPs on both independent provisioning of the associated bidirectional LSPs on both
sides, while the other enables single sided provisioning. The sides, while the other enables single-sided provisioning. The
REVERSE_LSP Object is also defined to enable a single endpoint to REVERSE_LSP Object is also defined to enable a single endpoint to
trigger creation of the reverse LSP and to specify parameters of the trigger creation of the reverse LSP and to specify parameters of the
reverse LSP in the single sided provisioning case. reverse LSP in the single-sided provisioning case.
Status of this Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
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Copyright Notice Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction ....................................................4
2. Conventions Used in This Document . . . . . . . . . . . . . . 4 2. Conventions Used in This Document ...............................5
2.1. Key Word Definitions . . . . . . . . . . . . . . . . . . . 4 2.1. Key Word Definitions .......................................5
2.2. Reverse Unidirectional LSPs . . . . . . . . . . . . . . . 4 2.2. Reverse Unidirectional LSPs ................................5
2.3. Message Formats . . . . . . . . . . . . . . . . . . . . . 4 2.3. Message Formats ............................................5
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Overview ........................................................6
3.1. Provisioning Model Overview . . . . . . . . . . . . . . . 4 3.1. Provisioning Model Overview ................................6
3.1.1. Single Sided Provisioning . . . . . . . . . . . . . . 5 3.1.1. Single-Sided Provisioning ...........................6
3.1.2. Double Sided Provisioning . . . . . . . . . . . . . . 5 3.1.2. Double-Sided Provisioning ...........................6
3.2. Association Signaling Overview . . . . . . . . . . . . . . 5 3.2. Association Signaling Overview .............................6
3.2.1. Single Sided Provisioning . . . . . . . . . . . . . . 6 3.2.1. Single-Sided Provisioning ...........................7
3.2.2. Double Sided Provisioning . . . . . . . . . . . . . . 6 3.2.2. Double-Sided Provisioning ...........................7
3.3. Asymmetric Bandwidth Signaling Overview . . . . . . . . . 6 3.3. Asymmetric Bandwidth Signaling Overview ....................8
3.3.1. Single Sided Provisioning . . . . . . . . . . . . . . 7 3.3.1. Single-Sided Provisioning ...........................8
3.3.2. Double Sided Provisioning . . . . . . . . . . . . . . 7 3.3.2. Double-Sided Provisioning ...........................8
3.4. Recovery LSP Overview . . . . . . . . . . . . . . . . . . 7 3.4. Recovery LSP Overview ......................................8
4. Message and Object Definitions . . . . . . . . . . . . . . . . 7 4. Message and Object Definitions ..................................9
4.1. RSVP Message Formats . . . . . . . . . . . . . . . . . . . 7 4.1. RSVP Message Formats .......................................9
4.2. ASSOCIATION Object . . . . . . . . . . . . . . . . . . . . 8 4.2. ASSOCIATION Object .........................................9
4.3. Extended ASSOCIATION Object . . . . . . . . . . . . . . . 9 4.3. Extended ASSOCIATION Object ...............................10
4.4. REVERSE_LSP Object Definition . . . . . . . . . . . . . . 9 4.4. REVERSE_LSP Object Definition .............................11
4.4.1. REVERSE_LSP Object Format . . . . . . . . . . . . . . 9 4.4.1. REVERSE_LSP Object Format ..........................11
4.4.2. REVERSE_LSP Subobjects . . . . . . . . . . . . . . . . 10 4.4.2. REVERSE_LSP Subobjects .............................11
5. Processing Rules . . . . . . . . . . . . . . . . . . . . . . . 10 5. Processing Rules ...............................................12
5.1. Rules For ASSOCIATION Object . . . . . . . . . . . . . . . 10 5.1. Rules for ASSOCIATION Object ..............................12
5.1.1. Compatibility For ASSOCIATION Object . . . . . . . . . 12 5.1.1. Compatibility for ASSOCIATION Object ...............14
5.2. Rules For REVERSE_LSP Object . . . . . . . . . . . . . . . 13 5.2. Rules for REVERSE_LSP Object ..............................14
5.2.1. Compatibility For REVERSE_LSP Object . . . . . . . . . 14 5.2.1. Compatibility for REVERSE_LSP Object ...............16
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 6. IANA Considerations ............................................16
6.1. Association Types . . . . . . . . . . . . . . . . . . . . 15 6.1. Association Types .........................................16
6.2. REVERSE_LSP Object . . . . . . . . . . . . . . . . . . . . 15 6.2. REVERSE_LSP Object ........................................16
6.3. Reverse LSP Failure PathErr Sub-code . . . . . . . . . . . 16 6.3. Reverse LSP Failure PathErr Sub-code ......................17
7. Security Considerations . . . . . . . . . . . . . . . . . . . 16 7. Security Considerations ........................................17
8. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 16 8. References .....................................................18
9. Contributing Authors . . . . . . . . . . . . . . . . . . . . . 17 8.1. Normative References ......................................18
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 8.2. Informative References ....................................19
10.1. Normative References . . . . . . . . . . . . . . . . . . 18 Acknowledgements ..................................................20
10.2. Informative References . . . . . . . . . . . . . . . . . 18 Contributors ......................................................20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20 Authors' Addresses ................................................20
1. Introduction 1. Introduction
The MPLS Transport Profile (MPLS-TP) requirements document [RFC5654] The MPLS Transport Profile (MPLS-TP) requirements document [RFC5654]
specifies that MPLS-TP MUST support associated bidirectional point- specifies that MPLS-TP MUST support associated bidirectional point-
to-point Label Switched Paths (LSPs). These requirements are given to-point Label Switched Paths (LSPs). These requirements are given
in Section 2.1 (General Requirements), and are repeated below: in Section 2.1 ("General Requirements") of that document and are
partially rephrased below:
7. MPLS-TP MUST support associated bidirectional point-to-point 7. MPLS-TP MUST support associated bidirectional point-to-point
LSPs. LSPs.
11. The end points of an associated bidirectional LSP MUST be aware 11. The end points of an associated bidirectional LSP MUST be aware
of the pairing relationship of the forward and reverse LSPs used to of the pairing relationship of the forward and reverse LSPs used
support the bidirectional service. to support the bidirectional service.
12. Nodes on the LSP of an associated bidirectional LSP where both 12. Nodes on the LSP of an associated bidirectional LSP where both
the forward and backward directions transit the same node in the same the forward and backward directions transit the same node in the
(sub)layer as the LSP SHOULD be aware of the pairing relationship of same (sub)layer as the LSP SHOULD be aware of the pairing
the forward and the backward directions of the LSP. relationship of the forward and the backward directions of the
LSP.
50. The MPLS-TP control plane MUST support establishing associated 50. The MPLS-TP control plane MUST support establishing associated
bidirectional P2P LSP including configuration of protection functions bidirectional P2P LSP including configuration of protection
and any associated maintenance functions. functions and any associated maintenance functions.
The above requirements are also repeated in [RFC6373]. The above requirements are also repeated in [RFC6373].
Furthermore, an associated bidirectional LSP is also useful for Furthermore, an associated bidirectional LSP is also useful for
protection switching for Operations, Administrations and Maintenance protection-switching for Operations, Administration, and Maintenance
(OAM) messages that require a return path. (OAM) messages that require a return path.
A variety of applications, such as Internet services and the return A variety of applications, such as Internet services and the return
paths of OAM messages, exist and which may have different upstream paths of OAM messages, exist and may have different upstream and
and downstream bandwidth requirements. [RFC5654] specifies an downstream bandwidth requirements. [RFC5654] specifies an asymmetric
asymmetric bandwidth requirement in Section 2.1 (General bandwidth requirement in Section 2.1 ("General Requirements"), and it
Requirements), and is repeated below: is repeated below:
14. MPLS-TP MUST support bidirectional LSPs with asymmetric 14. MPLS-TP MUST support bidirectional LSPs with asymmetric
bandwidth requirements, i.e., the amount of reserved bandwidth bandwidth requirements, i.e., the amount of reserved bandwidth
differs between the forward and backward directions. differs between the forward and backward directions.
The approach for supporting asymmetric bandwidth co-routed The approach for supporting asymmetric bandwidth co-routed
bidirectional LSPs is defined in [RFC6387]. bidirectional LSPs is defined in [RFC6387].
The method of association and the corresponding Resource reSerVation The method of association and the corresponding Resource Reservation
Protocol (RSVP) ASSOCIATION Object are defined in [RFC4872], Protocol (RSVP) ASSOCIATION Object are defined in [RFC4872],
[RFC4873] and [RFC6689]. In that context, the ASSOCIATION Object is [RFC4873], and [RFC6689]. In that context, the ASSOCIATION Object is
used to associate a recovery LSP with the LSP it is protecting. This used to associate a recovery LSP with the LSP it is protecting. This
object also has broader applicability as a mechanism to associate object also has broader applicability as a mechanism to associate
RSVP states. [RFC6780] defines the Extended ASSOCIATION Objects that RSVP states. [RFC6780] defines the Extended ASSOCIATION Objects that
can be more generally applied for this purpose. This document refers can be more generally applied for this purpose. This document uses
to the [RFC4872] defined ASSOCIATION Objects and the [RFC6780] the term "(Extended) ASSOCIATION Objects" to refer collectively to
defined the Extended ASSOCIATION Objects collectively as the the ASSOCIATION Objects defined in [RFC4872] and the Extended
(Extended) ASSOCIATION Objects. ASSOCIATION Objects defined in [RFC6780].
This document specifies mechanisms for binding two reverse This document specifies mechanisms for binding two reverse
unidirectional LSPs into an associated bidirectional LSP. The unidirectional LSPs into an associated bidirectional LSP. The
association is achieved by defining new Association Types for use in association is achieved by defining new Association Types for use in
(Extended) ASSOCIATION Objects. One of these types enables (Extended) ASSOCIATION Objects. One of these types enables
independent provisioning of the associated bidirectional LSPs, while independent provisioning of the associated bidirectional LSPs, while
the other enables single sided provisioning. The REVERSE_LSP Object the other enables single-sided provisioning. The REVERSE_LSP Object
is also defined to enable a single endpoint to trigger creation of is also defined to enable a single endpoint to trigger creation of
the reverse LSP and to specify parameters of the reverse LSP in the the reverse LSP and to specify parameters of the reverse LSP in the
single sided provisioning case. For example, the REVERSE_LSP Object single-sided provisioning case. For example, the REVERSE_LSP Object
allow asymmetric upstream and downstream bandwidths for the allow asymmetric upstream and downstream bandwidths for the
associated bidirectional LSP. associated bidirectional LSP.
2. Conventions Used in This Document 2. Conventions Used in This Document
2.1. Key Word Definitions 2.1. Key Word Definitions
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", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
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3.1. Provisioning Model Overview 3.1. Provisioning Model Overview
This section provides an overview and definition of the models for This section provides an overview and definition of the models for
provisioning associated bidirectional LSPs. provisioning associated bidirectional LSPs.
The associated bidirectional LSP's forward and reverse unidirectional The associated bidirectional LSP's forward and reverse unidirectional
LSPs are established, monitored, and protected independently as LSPs are established, monitored, and protected independently as
specified by [RFC5654]. Configuration information regarding the LSPs specified by [RFC5654]. Configuration information regarding the LSPs
can be provided at one or both endpoints of the associated can be provided at one or both endpoints of the associated
bidirectional LSP. Depending on the method chosen, there are two bidirectional LSP. Depending on the method chosen, there are two
models of creating an associated bidirectional LSP; single sided models of creating an associated bidirectional LSP -- single-sided
provisioning, and double sided provisioning. provisioning and double-sided provisioning.
3.1.1. Single Sided Provisioning 3.1.1. Single-Sided Provisioning
For the single sided provisioning, the Traffic Engineering (TE) For the single-sided provisioning, the Traffic Engineering (TE)
tunnel is configured only on one endpoint. An LSP for this tunnel is tunnel is configured only on one endpoint. An LSP for this tunnel is
initiated by the initiating endpoint with the (Extended) ASSOCIATION initiated by the initiating endpoint with the (Extended) ASSOCIATION
and REVERSE_LSP Objects inserted in the Path message. The other and REVERSE_LSP Objects inserted in the Path message. The other
endpoint then creates the corresponding reverse TE tunnel and signals endpoint then creates the corresponding reverse TE tunnel and signals
the reverse LSP in response using information from the REVERSE_LSP the reverse LSP in response using information from the REVERSE_LSP
Object and other Objects present in the received Path message. Object and other objects present in the received Path message.
3.1.2. Double Sided Provisioning 3.1.2. Double-Sided Provisioning
For the double sided provisioning, two unidirectional TE tunnels are For the double-sided provisioning, two unidirectional TE tunnels are
configured independently, one on each endpoint. The LSPs for the configured independently, one on each endpoint. The LSPs for the
tunnels are signaled with (Extended) ASSOCIATION Objects inserted in tunnels are signaled with (Extended) ASSOCIATION Objects inserted in
the Path message by both endpoints to indicate that the two LSPs are the Path message by both endpoints to indicate that the two LSPs are
to be associated to form a bidirectional LSP. to be associated to form a bidirectional LSP.
3.2. Association Signaling Overview 3.2. Association Signaling Overview
This section provides an overview of the association signaling This section provides an overview of the association signaling
methods for the associated bidirectional LSPs. methods for the associated bidirectional LSPs.
Three scenarios exist for binding two unidirectional LSPs together to Three scenarios exist for binding two unidirectional LSPs together to
form an associated bidirectional LSP. These are: 1) Neither form an associated bidirectional LSP. These are:
unidirectional LSP exists, and both must be established. 2) Both
unidirectional LSPs exist, but the association must be established. 1) Neither unidirectional LSP exists, and both must be established.
2) Both unidirectional LSPs exist, but the association must be
established.
3) One LSP exists, but the reverse associated LSP must be 3) One LSP exists, but the reverse associated LSP must be
established. Following sections describe the applicable provisioning established.
models for each of these scenarios.
Path Computation Element (PCE)-based approaches [RFC4655], may be The following sections describe the applicable provisioning models
used for path computation of an associated bidirectional LSP. for each of these scenarios.
However, these approaches are outside the scope of this document.
Consider the topology described in Figure 1 (an example of associated Path Computation Element (PCE)-based approaches [RFC4655] may be used
bidirectional LSP). LSP1 from node A to B, takes the path A,D,B and for path computation of an associated bidirectional LSP. However,
LSP2 from node B to A takes the path B,D,C,A. These two LSPs, once these approaches are outside the scope of this document.
established and associated, form an associated bidirectional LSP
between node A and node B. Consider the topology described in Figure 1. LSP1 from node A to B,
takes the path A,D,B, and LSP2 from node B to A takes the path
B,D,C,A. These two LSPs, once established and associated, form an
associated bidirectional LSP between nodes A and B.
LSP1 --> LSP1 -->
A-------D-------B A-------D-------B
\ / <-- LSP2 \ / <-- LSP2
\ / \ /
\ / \ /
C C
Figure 1: An example of associated bidirectional LSP Figure 1: An Example of Associated Bidirectional LSP
3.2.1. Single Sided Provisioning 3.2.1. Single-Sided Provisioning
For the single sided provisioning model, creation of reverse LSP1 For the single-sided provisioning model, creation of reverse LSP1
shown in Figure 1 is triggered by LSP2 or creation of reverse LSP2 is shown in Figure 1 is triggered by LSP2, or creation of reverse LSP2
triggered by LSP1. When creation of reverse LSP2 is triggered by is triggered by LSP1. When creation of reverse LSP2 is triggered by
LSP1, LSP1 is provisioned first (or refreshed if LSP1 already exists) LSP1, LSP1 is provisioned first (or refreshed, if LSP1 already
at node A. LSP1 is then signaled with an (Extended) ASSOCIATION and exists) at node A. LSP1 is then signaled with an (Extended)
REVERSE_LSP Objects inserted in the Path message. The Association ASSOCIATION, and REVERSE_LSP Objects are inserted in the Path
Type indicates single sided provisioning. Upon receiving this Path message. The Association Type indicates single-sided provisioning.
message for LSP1, node B establishes reverse LSP2. The (Extended) Upon receiving this Path message for LSP1, node B establishes reverse
ASSOCIATION Object inserted in LSP2's Path message is the same as LSP2. The (Extended) ASSOCIATION Object inserted in LSP2's Path
that received in LSP1's Path message. message is the same as that received in LSP1's Path message.
A similar procedure is used if LSP2 is provisioned first at node B A similar procedure is used if LSP2 is provisioned first at node B,
and the creation of reverse LSP1 at node A is triggered by LSP2. In and the creation of reverse LSP1 at node A is triggered by LSP2. In
both scenarios, the two unidirectional LSPs are bound together to both scenarios, the two unidirectional LSPs are bound together to
form an associated bidirectional LSP based on identical (Extended) form an associated bidirectional LSP based on identical (Extended)
ASSOCIATION Objects in the two LSPs' Path messages. ASSOCIATION Objects in the two LSPs' Path messages.
3.2.2. Double Sided Provisioning 3.2.2. Double-Sided Provisioning
For the double sided provisioning model, both LSP1 and LSP2 shown in For the double-sided provisioning model, both LSP1 and LSP2 shown in
Figure 1 are signaled independently with (Extended) ASSOCIATION Figure 1 are signaled independently with (Extended) ASSOCIATION
Objects inserted in the Path messages, in which the Association Type Objects inserted in the Path messages, in which the Association Type
indicating double sided provisioning is included. In this case, the indicating double-sided provisioning is included. In this case, the
two unidirectional LSPs are bound together to form an associated two unidirectional LSPs are bound together to form an associated
bidirectional LSP based on identical (Extended) ASSOCIATION Objects bidirectional LSP based on identical (Extended) ASSOCIATION Objects
in the two LSPs' Path messages. The LSPs to be selected for the in the two LSPs' Path messages. In all three scenarios described in
association are provisioned by the management action applied at both Section 3.2, the LSPs to be selected for the association are
endpoints in all three scenarios described above. provisioned by the management action applied at both endpoints.
3.3. Asymmetric Bandwidth Signaling Overview 3.3. Asymmetric Bandwidth Signaling Overview
This section provides an overview of the methods for signaling This section provides an overview of the methods for signaling
asymmetric upstream and downstream bandwidths for the associated asymmetric upstream and downstream bandwidths for the associated
bidirectional LSPs. bidirectional LSPs.
3.3.1. Single Sided Provisioning 3.3.1. Single-Sided Provisioning
A new REVERSE_LSP Object for use in the single sided provisioning A new REVERSE_LSP Object for use in the single-sided provisioning
model is defined in this document, in Section 4.4. The REVERSE_LSP model is defined in this document, in Section 4.4. The REVERSE_LSP
Object allows the initiating node of the single sided provisioned LSP Object allows the initiating node of the single-sided provisioned LSP
to trigger creation of the reverse LSP on the remote node. When the to trigger creation of the reverse LSP on the remote node. When the
single sided provisioning model is used, a SENDER_TSPEC Object can be single-sided provisioning model is used, a SENDER_TSPEC Object can be
added in the REVERSE_LSP Object as a subobject in the initiating added in the REVERSE_LSP Object as a subobject in the initiating
LSP's Path message to specify a different bandwidth for the reverse LSP's Path message to specify a different bandwidth for the reverse
LSP. As described in Section 4.4, addition of the REVERSE_LSP Object LSP. As described in Section 4.4, addition of the REVERSE_LSP Object
also allows the initiating node to control other aspects of the also allows the initiating node to control other aspects of the
reverse LSP (such as its path) by including other Objects in a reverse LSP (such as its path) by including other objects in a
REVERSE_LSP Object. REVERSE_LSP Object.
Consider again the topology described in Figure 1, where the creation Consider again the topology described in Figure 1, where the creation
of reverse LSP2 is triggered by LSP1. Node A signals LSP1 with the of reverse LSP2 is triggered by LSP1. Node A signals LSP1 with the
(Extended) ASSOCIATION Object with Association Type indicating single (Extended) ASSOCIATION Object with Association Type indicating
sided provisioning and inserts a SENDER_TSPEC subobject for use by single-sided provisioning and inserts a SENDER_TSPEC subobject for
LSP2 in the REVERSE_LSP Object in the Path message. Node B then use by LSP2 in the REVERSE_LSP Object in the Path message. Node B
establishes the LSP2 in the reverse direction using the asymmetric then establishes the LSP2 in the reverse direction using the
bandwidth thus specified by LSP1 and allows node A to control the asymmetric bandwidth thus specified by LSP1 and allows node A to
reverse LSP2. control the reverse LSP2.
3.3.2. Double Sided Provisioning 3.3.2. Double-Sided Provisioning
When the double sided provisioning model is used, the two When the double-sided provisioning model is used, the two
unidirectional LSPs are established with separate bandwidths, which unidirectional LSPs are established with separate bandwidths, which
may or may not be identical. However, these LSPs are associated may or may not be identical. However, these LSPs are associated
purely based on the identical contents of their (Extended) purely based on the identical contents of their (Extended)
ASSOCIATION Objects. ASSOCIATION Objects.
3.4. Recovery LSP Overview 3.4. Recovery LSP Overview
Recovery of each unidirectional LSP forming the bidirectional LSP is Recovery of each unidirectional LSP forming the bidirectional LSP is
independent [RFC5654] and is based on the parameters signaled in independent [RFC5654] and is based on the parameters signaled in
their respective RSVP Path messages. their respective RSVP Path messages.
Recovery LSP association is based on the identical content of the Recovery LSP association is based on the identical content of the
(Extended) ASSOCIATION Objects signaled in their Path messages during (Extended) ASSOCIATION Objects signaled in their Path messages during
the initial LSP setup for both single sided and double sided the initial LSP setup for both single-sided and double-sided
provisioning. As defined, see [RFC6780], multiple ASSOCIATION provisioning. As defined in [RFC6780], multiple ASSOCIATION Objects
Objects may be present in the signaling of a single LSP. may be present in the signaling of a single LSP.
4. Message and Object Definitions 4. Message and Object Definitions
4.1. RSVP Message Formats 4.1. RSVP Message Formats
This section presents the RSVP message-related formats as modified by This section presents the RSVP message-related formats as modified by
this document. Unmodified RSVP message formats are not listed. this document. Unmodified RSVP message formats are not listed.
The format of a Path message is as follows: The format of a Path message is as follows:
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4.2. ASSOCIATION Object 4.2. ASSOCIATION Object
The ASSOCIATION Object is populated using the rules defined below for The ASSOCIATION Object is populated using the rules defined below for
associating two reverse unidirectional LSPs to form an associated associating two reverse unidirectional LSPs to form an associated
bidirectional LSP. bidirectional LSP.
Association Types: Association Types:
In order to bind two reverse unidirectional LSPs to be an In order to bind two reverse unidirectional LSPs to be an
associated bidirectional LSP, the Association Type MUST be set to associated bidirectional LSP, the Association Type MUST be set to
indicate either single sided or double sided LSPs. indicate either single-sided or double-sided LSPs.
The new Association Types are defined as follows: The new Association Types are defined as follows:
Value Type Value Type
----- ----- ----- -----
3 Double Sided Associated Bidirectional LSP (D) 3 Double-Sided Associated Bidirectional LSP (D)
4 Single Sided Associated Bidirectional LSP (A) 4 Single-Sided Associated Bidirectional LSP (A)
Association ID: Association ID:
For both single sided and double sided provisioning, Association For both single-sided and double-sided provisioning, Association
ID MUST be set to a value assigned by the node that originates the ID MUST be set to a value assigned by the node that originates the
association for the bidirectional LSP. association for the bidirectional LSP.
Association Source: Association Source:
Association Source MUST be set to an address selected by the node Association Source MUST be set to an address selected by the node
that originates the association for the bidirectional LSP. For that originates the association for the bidirectional LSP. For
example, this may be a management entity, or in the case of single example, this may be a management entity or, in the case of
sided provisioning, an address assigned to the node that single-sided provisioning, an address assigned to the node that
originates the LSP. originates the LSP.
4.3. Extended ASSOCIATION Object 4.3. Extended ASSOCIATION Object
The Extended ASSOCIATION Object is populated using the rules defined The Extended ASSOCIATION Object is populated using the rules defined
below for associating two reverse unidirectional LSPs to form a below for associating two reverse unidirectional LSPs to form a
bidirectional LSP. bidirectional LSP.
The Association Type, Association ID and Association Source MUST be The Association Type, Association ID, and Association Source MUST be
set as defined for the ASSOCIATION Object in Section 4.1. set as defined for the ASSOCIATION Object in Section 4.1.
Global Association Source: Global Association Source:
For both single sided and double sided provisioning, Global For both single-sided and double-sided provisioning, Global
Association Source, when used, MUST be set to the Global_ID Association Source, when used, MUST be set to the Global_ID
[RFC6370] of the node that originates the association for the [RFC6370] of the node that originates the association for the
bidirectional LSP. bidirectional LSP.
Extended Association ID: Extended Association ID:
For both single sided and double sided provisioning, Extended For both single-sided and double-sided provisioning, Extended
Association ID, when used, MUST be set to a value selected by the Association ID, when used, MUST be set to a value selected by the
node that originates the association for the bidirectional LSP. node that originates the association for the bidirectional LSP.
4.4. REVERSE_LSP Object Definition 4.4. REVERSE_LSP Object Definition
4.4.1. REVERSE_LSP Object Format 4.4.1. REVERSE_LSP Object Format
The REVERSE_LSP Object is carried in the Path message of a forward The REVERSE_LSP Object is carried in the Path message of a forward
LSP to provide information to be used by the reverse LSP. The object LSP to provide information to be used by the reverse LSP. The object
also indicates that the LSP is the forward LSP of a single sided also indicates that the LSP is the forward LSP of a single-sided
provisioned associated bidirectional LSP. associated bidirectional LSP.
The Object has the following format: The Object has the following format:
Class_Num = 203, C_Type = 1. Class_Num = 203, C_Type = 1.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// (Subobjects) // // (Subobjects) //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.4.2. REVERSE_LSP Subobjects 4.4.2. REVERSE_LSP Subobjects
Subobjects are used to override the default contents of Path message Subobjects are used to override the default contents of a Path
of a Reverse LSP, see Section 5.2. The contents of a REVERSE_LSP message of a reverse LSP; see Section 5.2. The contents of a
Object is zero or more variable length subobjects that have the same REVERSE_LSP Object is zero or more variable-length subobjects that
format as RSVP Objects, see Section 3.1.2 of [RFC2205]. Any Object have the same format as RSVP Objects; see Section 3.1.2 of [RFC2205].
that may be carried in a Path message MAY be carried in the Any object that may be carried in a Path message MAY be carried in
REVERSE_LSP Object. Subobject ordering MUST follow any Path message the REVERSE_LSP Object. Subobject ordering MUST follow any Path
Object ordering requirements. message Object ordering requirements.
Examples of the Path message Objects that can be carried in the Examples of the Path message Objects that can be carried in the
REVERSE_LSP Object are (but not limited to): REVERSE_LSP Object are (but not limited to):
- SENDER_TSPEC [RFC2205] - SENDER_TSPEC [RFC2205]
- EXPLICIT_ROUTE Object (ERO) [RFC3209] - EXPLICIT_ROUTE Object (ERO) [RFC3209]
- SESSION_ATTRIBUTE Object [RFC3209] - SESSION_ATTRIBUTE Object [RFC3209]
- ADMIN_STATUS Object [RFC3473] - ADMIN_STATUS Object [RFC3473]
- LSP_REQUIRED_ATTRIBUTES Object [RFC5420] - LSP_REQUIRED_ATTRIBUTES Object [RFC5420]
- PROTECTION Object [RFC3473] [RFC4872] - PROTECTION Object [RFC3473] [RFC4872]
5. Processing Rules 5. Processing Rules
In general, the processing rules for the ASSOCIATION Object are as In general, the processing rules for the ASSOCIATION Object are as
specified in [RFC4872] and Extended ASSOCIATION Object are specified specified in [RFC4872], and those for the Extended ASSOCIATION Object
in [RFC6780]. Following sections describe the rules for processing are as specified in [RFC6780]. The following sections describe the
(Extended) ASSOCIATION Object for both double sided and single sided rules for processing (Extended) ASSOCIATION Objects for both double-
associated bidirectional LSPs and REVERSE_LSP Object for single sided sided and single-sided associated bidirectional LSPs and REVERSE_LSP
associated bidirectional LSPs. Objects for single-sided associated bidirectional LSPs.
5.1. Rules For ASSOCIATION Object 5.1. Rules for ASSOCIATION Object
This section defines the processing for the association of two This section defines the processing for the association of two
unidirectional LSPs to form an associated bidirectional LSP. Such unidirectional LSPs to form an associated bidirectional LSP. Such
association is based on the use of an (Extended) ASSOCIATION Object. association is based on the use of an (Extended) ASSOCIATION Object.
The procedures related to the actual identification of associations The procedures related to the actual identification of associations
between LSPs based on (Extended) ASSOCIATION Objects are defined in between LSPs based on (Extended) ASSOCIATION Objects are defined in
[RFC6780]. [RFC6780] specifies that in the absence of Association [RFC6780]. [RFC6780] specifies that in the absence of rules for
Type-specific rule for identifying association, the included identifying the association that are specific to the Association
(Extended) ASSOCIATION Objects in the LSPs MUST be identical in order Type, the included (Extended) ASSOCIATION Objects in the LSPs MUST be
for an association to exist. This document adds no specific rules identical in order for an association to exist. This document adds
for the new Association Types defined, and the identification of LSP no specific rules for the new Association Types defined, and the
association therefore proceeds as specified in [RFC6780]. identification of an LSP association therefore proceeds as specified
in [RFC6780].
As described in [RFC6780], association of LSPs can be upstream or As described in [RFC6780], association of LSPs can be upstream or
downstream initiated, as indicated by (Extended) ASSOCIATION Objects downstream initiated, as indicated by (Extended) ASSOCIATION Objects
in Path or Resv Messages. The association of bidirectional LSPs is in Path or Resv Messages. The association of bidirectional LSPs is
always upstream initialized, therefore the Association Types defined always upstream initiated; therefore, the Association Types defined
in this document are only to be interpreted in Path Messages. These in this document are only to be interpreted in Path Messages. These
types SHOULD NOT be used in ASSOCIATION Objects carried in Resv types SHOULD NOT be used in ASSOCIATION Objects carried in Resv
messages and SHOULD be ignored if present. messages and SHOULD be ignored if present.
To indicate an associated bidirectional LSP, an ingress node MUST To indicate an associated bidirectional LSP, an ingress node MUST
insert an (Extended) ASSOCIATION Object into the Path message of the insert an (Extended) ASSOCIATION Object into the Path message of the
unidirectional LSP that is part of the associated bidirectional LSP unidirectional LSP that is part of the associated bidirectional LSP
it initiates. If either Global Association Source or Extended it initiates. If either Global Association Source or Extended
Association Address is required, then an Extended ASSOCIATION Object Association Address is required, then an Extended ASSOCIATION Object
[RFC6780] MUST be inserted in the Path message. Otherwise, an [RFC6780] MUST be inserted in the Path message. Otherwise, an
ASSOCIATION Object MAY be used. (Extended) ASSOCIATION Objects with ASSOCIATION Object MAY be used. (Extended) ASSOCIATION Objects with
both single sided and double sided Association Types MUST NOT be both single-sided and double-sided Association Types MUST NOT be
added or sent in the same Path message. added or sent in the same Path message.
The ingress node MUST set the Association Type field in the The ingress node MUST set the Association Type field in the
(Extended) ASSOCIATION Object to "Single Sided Associated (Extended) ASSOCIATION Object to "Single-Sided Associated
Bidirectional LSP" when single sided provisioning is used, and to Bidirectional LSP" when single-sided provisioning is used, and to
"Double Sided Associated Bidirectional LSP" when double sided "Double-Sided Associated Bidirectional LSP" when double-sided
provisioning is used. provisioning is used.
A transit node MAY identify the unidirectional LSPs of an associated A transit node MAY identify the unidirectional LSPs of an associated
bidirectional LSP based on (Extended) ASSOCIATION Objects, with the bidirectional LSP based on (Extended) ASSOCIATION Objects, with the
Association Type values defined in this document, carried in Path Association Type values defined in this document, carried in Path
messages. Clearly, such associations are only possible when the LSPs messages. Clearly, such associations are only possible when the LSPs
transit the node. As mentioned above, such associations are made per transit the node. As mentioned above, such associations are made per
the rules defined in [RFC6780]. the rules defined in [RFC6780].
Egress nodes which support the Association Types defined in this Egress nodes that support the Association Types defined in this
document identify the unidirectional LSPs of an associated document identify the unidirectional LSPs of an associated
bidirectional LSP based on (Extended) ASSOCIATION Objects carried in bidirectional LSP based on (Extended) ASSOCIATION Objects carried in
Path messages. Note that an ingress node will normally be the Path messages. Note that an ingress node will normally be the
ingress for one of the unidirectional LSPs that make up an associated ingress for one of the unidirectional LSPs that make up an associated
bidirectional LSP. When an egress node receives a Path message bidirectional LSP. When an egress node receives a Path message
containing an (Extended) ASSOCIATION Object with one of the containing an (Extended) ASSOCIATION Object with one of the
Association Types defined in this document, it MUST attempt to Association Types defined in this document, it MUST attempt to
identify other LSPs (including ones for which it is an ingress node) identify other LSPs (including ones for which it is an ingress node)
with which the LSP being processed is associated. As defined above, with which the LSP being processed is associated. As defined above,
such associations are made per the rules defined in [RFC6780]. An such associations are made per the rules defined in [RFC6780]. An
skipping to change at page 12, line 18 skipping to change at page 13, line 34
during rerouting or re-optimization) on an egress node is not during rerouting or re-optimization) on an egress node is not
necessarily considered an error condition. necessarily considered an error condition.
Associated bidirectional LSP teardown follows the standard procedures Associated bidirectional LSP teardown follows the standard procedures
defined in [RFC3209] and [RFC3473] either without or with the defined in [RFC3209] and [RFC3473] either without or with the
administrative status. Generally, the teardown procedures of the administrative status. Generally, the teardown procedures of the
unidirectional LSPs forming an associated bidirectional LSP are unidirectional LSPs forming an associated bidirectional LSP are
independent of each other, so it is possible that while one LSP independent of each other, so it is possible that while one LSP
follows graceful teardown with administrative status, the reverse LSP follows graceful teardown with administrative status, the reverse LSP
is torn down without administrative status (using is torn down without administrative status (using
PathTear/ResvTear/PathErr with state removal). See Section 5.2 below PathTear/ResvTear/PathErr with state removal). See Section 5.2 for
for additional rules related to LSPs established using single sided additional rules related to LSPs established using single-sided
provisioning. provisioning.
When an LSP signaled with a Path message containing an (Extended) When an LSP signaled with a Path message containing an (Extended)
ASSOCIATION Object with an Association Type defined in this document ASSOCIATION Object with an Association Type defined in this document
is torn down, the processing node SHALL remove the binding of the LSP is torn down, the processing node SHALL remove the binding of the LSP
to any previously identified associated bidirectional LSP. to any previously identified associated bidirectional LSP.
No additional processing is needed for Path messages with an No additional processing is needed for Path messages with an
(Extended) ASSOCIATION Object containing an Association Type field of (Extended) ASSOCIATION Object containing an Association Type field
Double Sided Associated Bidirectional LSP. set to "Double-Sided Associated Bidirectional LSP".
5.1.1. Compatibility For ASSOCIATION Object 5.1.1. Compatibility for ASSOCIATION Object
The ASSOCIATION Object has been defined in [RFC4872] and the Extended The ASSOCIATION Object has been defined in [RFC4872] and the Extended
ASSOCIATION Object has been defined in [RFC6780], both with class ASSOCIATION Object has been defined in [RFC6780], both with class
numbers in the form 11bbbbbb, which ensures compatibility with numbers in the form 11bbbbbb, which ensures compatibility with non-
non-supporting nodes. Per [RFC2205], such nodes will ignore the supporting nodes. Per [RFC2205], such nodes will ignore the object
object but forward it without modification. but forward it without modification.
Operators wishing to use a function supported by a particular Operators wishing to use a function supported by a particular
association type SHOULD ensure that the type is supported on any node Association Type SHOULD ensure that the type is supported on any node
that is expected to act on the association [RFC6780]. that is expected to act on the association [RFC6780].
An egress node that does not support the Association Types defined in An egress node that does not support the Association Types defined in
this document, is expected to return a PathErr with Error Code this document is expected to return a PathErr with Error Code
"Admission Control Failure (01) [RFC2205]" and Sub-code "Bad "Admission Control Failure" (1) [RFC2205] and Sub-code "Bad
Association Type (5) [RFC4872]". Association Type" (5) [RFC4872].
LSP recovery as defined in [RFC4872] and [RFC4873] is not impacted by LSP recovery as defined in [RFC4872] and [RFC4873] is not impacted by
this document. The recovery mechanisms defined in [RFC4872] and this document. The recovery mechanisms defined in [RFC4872] and
[RFC4873] rely on the use of the (Extended) ASSOCIATION Objects, but [RFC4873] rely on the use of the (Extended) ASSOCIATION Objects, but
use a different value for Association Type; multiple ASSOCIATION they use a different value for Association Type; multiple ASSOCIATION
Objects can be present in the LSP Path message and can coexist with Objects can be present in the LSP Path message and can coexist with
the procedures defined in this document. the procedures defined in this document.
5.2. Rules For REVERSE_LSP Object 5.2. Rules for REVERSE_LSP Object
When a node initiates setup of an LSP using a PATH message containing When a node initiates setup of an LSP using a Path message containing
an ASSOCIATION or Extended ASSOCIATION Object, and the Association an ASSOCIATION or Extended ASSOCIATION Object, and the Association
Type set to "Single Sided Associated Bidirectional LSP", the PATH Type set to "Single-Sided Associated Bidirectional LSP", the Path
message MUST carry the REVERSE_LSP Object to trigger creation of a message MUST carry the REVERSE_LSP Object to trigger creation of a
reverse LSP on the egress node. reverse LSP on the egress node.
The REVERSE_LSP subobject MAY contain any of object that the The REVERSE_LSP subobject MAY contain any of the objects that the
initiating node desires to have included in the Path message for the initiating node desires to have included in the Path message for the
associated reverse LSP. The REVERSE_LSP Object SHOULD NOT be associated reverse LSP. The REVERSE_LSP Object SHOULD NOT be
included in a REVERSE_LSP Object. included in a REVERSE_LSP Object.
A transit node receiving a valid Path message containing a A transit node receiving a valid Path message containing a
REVERSE_LSP Object MUST forward the REVERSE_LSP Object unchanged in REVERSE_LSP Object MUST forward the REVERSE_LSP Object unchanged in
the outgoing Path message. the outgoing Path message.
An egress node, upon receiving a Path message containing an An egress node, upon receiving a Path message containing an
REVERSE_LSP Object MUST verify that the Path message contains an REVERSE_LSP Object MUST verify that the Path message contains an
ASSOCIATION or Extended ASSOCIATION Object with the Association Type ASSOCIATION or Extended ASSOCIATION Object with the Association Type
set to "Single Sided Associated Bidirectional LSP". If it does not, set to "Single-Sided Associated Bidirectional LSP". If it does not,
the Path message MUST NOT trigger a reverse LSP. This verification the Path message MUST NOT trigger a reverse LSP. This verification
failure SHOULD NOT trigger any RSVP message but can be logged failure SHOULD NOT trigger any RSVP message but can be logged
locally, and perhaps reported through network management mechanisms. locally, and perhaps reported through network management mechanisms.
Once validated, the egress node MUST create an LSP in the reverse Once validated, the egress node MUST create an LSP in the reverse
direction or reject the Path message. If the creation of a reverse direction or reject the Path message. If the creation of a reverse
LSP fails, the egress node MUST return a PathErr with Error code LSP fails, the egress node MUST return a PathErr with Error Code
"Admission Control Failure (01) [RFC2205]" and Sub-code "Reverse LSP "Admission Control Failure" (1) [RFC2205] and Sub-code "Reverse LSP
Failure" defined in this document. Note that normal Resv processing Failure" (6) defined in this document. Note that normal Resv
SHOULD NOT be impacted by the presence of an ASSOCIATION Object with processing SHOULD NOT be impacted by the presence of an ASSOCIATION
an Association Type set to "Single Sided Associated Bidirectional Object with an Association Type set to "Single-Sided Associated
LSP". Bidirectional LSP".
The egress node MUST use the subobjects contained in the REVERSE_LSP The egress node MUST use the subobjects contained in the REVERSE_LSP
Object for initiating the reverse LSP. When a subobject is not Object for initiating the reverse LSP. When a subobject is not
present in the received REVERSE_LSP Object, the egress node SHOULD present in the received REVERSE_LSP Object, the egress node SHOULD
initiate the reverse LSP based on the information contained in the initiate the reverse LSP based on the information contained in the
received Path message of the forward LSP as follows: received Path message of the forward LSP as follows:
o The egress node SHOULD copy the information from the received o The egress node SHOULD copy the information from the received
SESSION_ATTRIBUTE, CLASS_TYPE, LABEL_REQUEST, ASSOCIATION, SESSION_ATTRIBUTE, CLASS_TYPE, LABEL_REQUEST, ASSOCIATION,
ADMIN_STATUS and PROTECTION Objects in the forward LSP Path message ADMIN_STATUS, and PROTECTION Objects in the forward LSP Path
to form the Path message of the reverse LSP when the object is not message to form the Path message of the reverse LSP when the
present in the received REVERSE_LSP Object. object is not present in the received REVERSE_LSP Object.
o The IP address in the reverse LSP's SESSION Object SHOULD be set o The IP address in the reverse LSP's SESSION Object SHOULD be set
to the IP address carried in the received SENDER_TEMPLATE Object, and to the IP address carried in the received SENDER_TEMPLATE Object;
conversely the IP address in the SENDER_TEMPLATE Object SHOULD be set and conversely, the IP address in the SENDER_TEMPLATE Object
to the IP address carried in the received SESSION Object. There are SHOULD be set to the IP address carried in the received SESSION
no additional requirements related to the IDs carried in the SESSION Object. There are no additional requirements related to the IDs
and SENDER_TEMPLATE Objects. carried in the SESSION and SENDER_TEMPLATE Objects.
o When the forward LSP Path message contains a RECORD_ROUTE Object, o When the forward LSP Path message contains a RECORD_ROUTE Object,
the egress node SHOULD include the received RECORD_ROUTE Object in the egress node SHOULD include the received RECORD_ROUTE Object in
the reverse LSP Path message. Local node information SHOULD also be the reverse LSP Path message. Local node information SHOULD also
recorded per Standard Path message processing. be recorded per standard Path message processing.
o There are no specific requirements related to other objects. o There are no specific requirements related to other objects.
The resulting Path message is used to create the reverse LSP. From The resulting Path message is used to create the reverse LSP. From
this point on, Standard Path message processing is used in processing this point on, standard Path message processing is used in processing
the resulting Path message. the resulting Path message.
Note that the contents of a forward LSP, including a carried Note that the contents of a forward LSP, including a carried
REVERSE_LSP Object, may change over the life of an LSP and such REVERSE_LSP Object, may change over the life of an LSP, and such
changes MUST result in corresponding changes in the reverse LSP. In changes MUST result in corresponding changes in the reverse LSP. In
particular, any object or subobject that was copied during the particular, any object or subobject that was copied during the
creation of the initial reverse LSP's Path message MUST be copied creation of the initial reverse LSP's Path message MUST be copied
when modified in the forward LSP, and a trigger Path message MUST be when modified in the forward LSP, and a trigger Path message MUST be
processed. processed.
The removal of the REVERSE_LSP Object in the received Path message The removal of the REVERSE_LSP Object in the received Path message
SHOULD cause the egress node to teardown any previously established SHOULD cause the egress node to tear down any previously established
reverse LSP. reverse LSP.
When the egress node receives a PathTear message for the forward LSP When the egress node receives a PathTear message for the forward LSP
or whenever the forward LSP is torn down, the node MUST remove the or whenever the forward LSP is torn down, the node MUST remove the
associated reverse LSP using Standard PathTear message processing. associated reverse LSP using standard PathTear message processing.
Tear down of the reverse LSP for other reasons SHOULD NOT trigger Teardown of the reverse LSP for other reasons SHOULD NOT trigger
removal of the initiating LSP, but SHOULD result in the egress node removal of the initiating LSP, but it SHOULD result in the egress
sending a PathErr with Error code "Admission Control Failure (01) node sending a PathErr with Error Code "Admission Control Failure"
[RFC2205]" and Sub-code "Reverse LSP Failure" defined in this (1) [RFC2205] and Sub-code "Reverse LSP Failure" (6) defined in this
document. document.
5.2.1. Compatibility For REVERSE_LSP Object 5.2.1. Compatibility for REVERSE_LSP Object
The REVERSE_LSP Object is defined with class numbers in the form The REVERSE_LSP Object is defined with class numbers in the form
11bbbbbb, which ensures compatibility with non-supporting nodes. Per 11bbbbbb, which ensures compatibility with non-supporting nodes. Per
[RFC2205], such nodes will ignore the object but forward it without [RFC2205], such nodes will ignore the object but forward it without
modification. modification.
6. IANA Considerations 6. IANA Considerations
IANA is requested to administer assignment of new values for IANA has registered values for the namespace defined in this document
namespace defined in this document and summarized in this section. and summarized in this section.
6.1. Association Types 6.1. Association Types
IANA maintains the "Generalized Multi-Protocol Label Switching IANA maintains the "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Parameters" registry (see (GMPLS) Signaling Parameters" registry (see
http://www.iana.org/assignments/gmpls-sig-parameters). "Association <http://www.iana.org/assignments/gmpls-sig-parameters>). The
Type" subregistry is included in this registry. "Association Type" subregistry is included in this registry.
This registry will be updated by new Association Types for This registry has been updated by new Association Types for
ASSOCIATION and Extended ASSOCIATION Objects defined in this document ASSOCIATION and Extended ASSOCIATION Objects defined in this document
as follows: as follows:
Value Name Reference Value Name Reference
3 Double Sided Associated Bidirectional LSP (D) Section 4.2 3 Double-Sided Associated Bidirectional LSP (D) Section 4.2
4 Single Sided Associated Bidirectional LSP (A) Section 4.2 4 Single-Sided Associated Bidirectional LSP (A) Section 4.2
Specified Association Type values are temporary early allocations as
per RFC7120.
6.2. REVERSE_LSP Object 6.2. REVERSE_LSP Object
IANA maintains the "RSVP Parameters" registry (see IANA maintains the "Resource Reservation Protocol (RSVP) Parameters"
http://www.iana.org/assignments/rsvp-parameters/rsvp-parameters.xml). registry (see <http://www.iana.org/assignments/rsvp-parameters>).
Class Names, Class Numbers, and Class Types subregistry is included The "Class Names, Class Numbers, and Class Types" subregistry is
in this registry. included in this registry.
This registry will be extended for new Class Number (Class-Num) and This registry has been extended for new Class Number (Class-Num) and
Class Type (C-type) for RSVP REVERSE_LSP Object requested in the Class Type (C-type) for RSVP REVERSE_LSP Object requested in the
11bbbbbb range defined in this document as follows: 11bbbbbb range defined in this document as follows:
Class Number Class Name Reference Class Number Class Name Reference
203 REVERSE_LSP Section 4.4 203 REVERSE_LSP Section 4.4
o REVERSE_LSP : Class Type or C-type = 1 o REVERSE_LSP : Class Type or C-type = 1
Specified REVERSE_LSP Class Number and Class Type values are
temporary early allocations as per RFC7120.
6.3. Reverse LSP Failure PathErr Sub-code 6.3. Reverse LSP Failure PathErr Sub-code
IANA maintains the "RSVP Parameters" registry (see IANA maintains the "Resource Reservation Protocol (RSVP) Parameters"
http://www.iana.org/assignments/rsvp-parameters/rsvp-parameters.xml). registry (see <http://www.iana.org/assignments/rsvp-parameters>).
Error Codes and Globally-Defined Error Value Sub-Codes subregistry is The "Error Codes and Globally-Defined Error Value Sub-Codes"
included in this registry. subregistry is included in this registry.
This registry will be extended for the new PathErr Sub-code defined This registry has been extended for the new PathErr Sub-code defined
in this document as follows: in this document as follows:
Error Code = 01: "Admission Control Failure" (see [RFC2205]) Error Code = 01: "Admission Control Failure" (see [RFC2205])
o "Admission Control Failure/Reverse LSP Failure" (TBA) o "Reverse LSP Failure" (6)
There are no other IANA considerations introduced by this document.
7. Security Considerations 7. Security Considerations
This document introduces two new Association Types for the (Extended) This document introduces two new Association Types for the (Extended)
ASSOCIATION Object, double sided associated bidirectional LSP and ASSOCIATION Object, Double-Sided Associated Bidirectional LSP and
single sided associated bidirectional LSP. The introduction of these Single-Sided Associated Bidirectional LSP. These types, by
types, by themselves, introduce no additional information to themselves, introduce no additional information to signaling.
signaling. Related security considerations are already covered for Related security considerations are already covered for this in RFC
this in RFC6780. 6780.
The REVERSE_LSP Object is carried in the Path message of a forward The REVERSE_LSP Object is carried in the Path message of a forward
LSP of the single sided associated bidirectional LSP. It can carry LSP of the single-sided associated bidirectional LSP. It can carry
parameters for the reverse LSP. This does allow for additional parameters for the reverse LSP. This does allow for additional
information to be conveyed, but this information is not fundamentally information to be conveyed, but this information is not fundamentally
different from the information that is already carried in a different from the information that is already carried in a
bidirectional LSP message. The processing of such messages are bidirectional LSP message. The processing of such messages is
already subject to local policy, as well as security considerations already subject to local policy as well as security considerations
discussions. For a general discussion on MPLS and GMPLS related discussions. For a general discussion on MPLS- and GMPLS-related
security issues, see the MPLS/GMPLS security framework [RFC5920]. security issues, see the MPLS/GMPLS security framework [RFC5920].
8. Acknowledgement 8. References
The authors would like to thank Lou Berger and George Swallow for
their great guidance in this work, Jie Dong for the discussion of
recovery, Lamberto Sterling for his valuable comments on the section
of asymmetric bandwidths, Attila Takacs for the discussion of the
provisioning model and Lou Berger, Daniel King and Deborah Brungard
for the review of the document. At the same time, the authors would
also like to acknowledge the contributions of Bo Wu, Xihua Fu,
Lizhong Jin for the initial discussions, and Wenjuan He for the
prototype implementation. The authors would also like to thank Siva
Sivabalan, Eric Osborne and Robert Sawaya for the discussions on the
ASSOCIATION Object. The authors would like to thank Matt Hartley for
providing useful suggestions on the document and Lou Berger for
careful editorial reviews.
9. Contributing Authors
Fan Yang
ZTE
Email: yang.fan240347@gmail.com
Weilian Jiang
ZTE
Email: jiang.weilian@gmail.com
10. References
10.1. Normative References 8.1. Normative References
[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,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, September 1997. Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
September 1997, <http://www.rfc-editor.org/info/rfc2205>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001. Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<http://www.rfc-editor.org/info/rfc3209>.
[RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching [RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label
(GMPLS) Signaling Resource ReserVation Protocol-Traffic Switching (GMPLS) Signaling Resource ReserVation Protocol-
Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
DOI 10.17487/RFC3473, January 2003,
<http://www.rfc-editor.org/info/rfc3473>.
[RFC4872] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE [RFC4872] Lang, J., Ed., Rekhter, Y., Ed., and D. Papadimitriou,
Extensions in Support of End-to-End Generalized Multi- Ed., "RSVP-TE Extensions in Support of End-to-End
Protocol Label Switching (GMPLS) Recovery", RFC 4872, May Generalized Multi-Protocol Label Switching (GMPLS)
2007. Recovery", RFC 4872, DOI 10.17487/RFC4872, May 2007,
<http://www.rfc-editor.org/info/rfc4872>.
[RFC4873] Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel, [RFC4873] Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel,
"GMPLS Segment Recovery", RFC 4873, May 2007. "GMPLS Segment Recovery", RFC 4873, DOI 10.17487/RFC4873,
May 2007, <http://www.rfc-editor.org/info/rfc4873>.
[RFC6780] Berger, L., Le Faucheur, F., and A. Narayanan, "RSVP
Association Object Extensions", RFC 6780, October 2012.
[RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF) - A Syntax [RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
Used to Form Encoding Rules in Various Routing Protocol Used to Form Encoding Rules in Various Routing Protocol
Specifications", RFC 5511, April 2009. Specifications", RFC 5511, DOI 10.17487/RFC5511, April
2009, <http://www.rfc-editor.org/info/rfc5511>.
10.2. Informative References [RFC6780] Berger, L., Le Faucheur, F., and A. Narayanan, "RSVP
ASSOCIATION Object Extensions", RFC 6780,
DOI 10.17487/RFC6780, October 2012,
<http://www.rfc-editor.org/info/rfc6780>.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation 8.2. Informative References
Element (PCE)-Based Architecture", RFC 4655, August 2006.
[RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
Computation Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<http://www.rfc-editor.org/info/rfc4655>.
[RFC5420] Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and A. [RFC5420] Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and A.
Ayyangarps, "Encoding of Attributes for MPLS LSP Ayyangarps, "Encoding of Attributes for MPLS LSP
Establishment Using Resource Reservation Protocol Traffic Establishment Using Resource Reservation Protocol Traffic
Engineering (RSVP-TE)", RFC 5420, February 2009. Engineering (RSVP-TE)", RFC 5420, DOI 10.17487/RFC5420,
February 2009, <http://www.rfc-editor.org/info/rfc5420>.
[RFC5654] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., [RFC5654] Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed.,
and S. Ueno, "Requirements of an MPLS Transport Profile", Sprecher, N., and S. Ueno, "Requirements of an MPLS
RFC 5654, September 2009. Transport Profile", RFC 5654, DOI 10.17487/RFC5654,
September 2009, <http://www.rfc-editor.org/info/rfc5654>.
[RFC5920] Fang, L., "Security Framework for MPLS and GMPLS [RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, July 2010. Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
<http://www.rfc-editor.org/info/rfc5920>.
[RFC6370] Bocci, M., Swallow, G., and E. Gray, "MPLS Transport [RFC6370] Bocci, M., Swallow, G., and E. Gray, "MPLS Transport
Profile (MPLS-TP) Identifiers", RFC 6370, September 2011. Profile (MPLS-TP) Identifiers", RFC 6370,
DOI 10.17487/RFC6370, September 2011,
<http://www.rfc-editor.org/info/rfc6370>.
[RFC6373] Andersson, L., Berger, L., Fang, L., Bitar, N., and E. [RFC6373] Andersson, L., Ed., Berger, L., Ed., Fang, L., Ed., Bitar,
Gray, "MPLS Transport Profile (MPLS-TP) Control Plane N., Ed., and E. Gray, Ed., "MPLS Transport Profile
Framework", RFC 6373, September 2011. (MPLS-TP) Control Plane Framework", RFC 6373,
DOI 10.17487/RFC6373, September 2011,
<http://www.rfc-editor.org/info/rfc6373>.
[RFC6387] Takacs, A., Berger, L., Caviglia, D., Fedyk, D., and J. [RFC6387] Takacs, A., Berger, L., Caviglia, D., Fedyk, D., and J.
Meuric, "GMPLS Asymmetric Bandwidth Bidirectional Label Meuric, "GMPLS Asymmetric Bandwidth Bidirectional Label
Switched Paths (LSPs)", RFC 6387, September 2011. Switched Paths (LSPs)", RFC 6387, DOI 10.17487/RFC6387,
September 2011, <http://www.rfc-editor.org/info/rfc6387>.
[RFC6689] Berger, L., "Usage of The RSVP Association Object", RFC [RFC6689] Berger, L., "Usage of the RSVP ASSOCIATION Object",
6689, July 2012. RFC 6689, DOI 10.17487/RFC6689, July 2012,
<http://www.rfc-editor.org/info/rfc6689>.
Acknowledgements
The authors would like to thank Lou Berger and George Swallow for
their great guidance in this work; Jie Dong for the discussion of the
recovery LSP; Lamberto Sterling for his valuable comments about
asymmetric bandwidth signaling; Attila Takacs for the discussion of
the provisioning model; Siva Sivabalan, Eric Osborne, and Robert
Sawaya for the discussions on the ASSOCIATION Object; and Matt
Hartley for providing useful suggestions on the document. At the
same time, the authors would like to acknowledge the contributions of
Bo Wu, Xihua Fu, and Lizhong Jin for the initial discussions; Wenjuan
He for the prototype implementation; and Lou Berger, Daniel King, and
Deborah Brungard for the review of the document.
Contributors
Fan Yang
ZTE
EMail: yang.fan240347@gmail.com
Weilian Jiang
ZTE
EMail: jiang.weilian@gmail.com
Authors' Addresses Authors' Addresses
Fei Zhang (editor) Fei Zhang (editor)
Huawei Huawei
Email: zhangfei7@huawei.com EMail: zhangfei7@huawei.com
Ruiquan Jing Ruiquan Jing
China Telecom China Telecom
Email: jingrq@ctbri.com.cn EMail: jingrq@ctbri.com.cn
Rakesh Gandhi (editor) Rakesh Gandhi (editor)
Cisco Systems Cisco Systems
Email: rgandhi@cisco.com EMail: rgandhi@cisco.com
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