rfc9514.original   rfc9514.txt 
Inter-Domain Routing G. Dawra Internet Engineering Task Force (IETF) G. Dawra
Internet-Draft LinkedIn Request for Comments: 9514 LinkedIn
Intended status: Standards Track C. Filsfils Category: Standards Track C. Filsfils
Expires: 21 August 2023 K. Talaulikar, Ed. ISSN: 2070-1721 K. Talaulikar, Ed.
Cisco Systems Cisco Systems
M. Chen M. Chen
Huawei Huawei
D. Bernier D. Bernier
Bell Canada Bell Canada
B. Decraene B. Decraene
Orange Orange
17 February 2023 November 2023
BGP Link State Extensions for SRv6 Border Gateway Protocol - Link State (BGP-LS) Extensions for Segment
draft-ietf-idr-bgpls-srv6-ext-14 Routing over IPv6 (SRv6)
Abstract Abstract
Segment Routing over IPv6 (SRv6) allows for a flexible definition of Segment Routing over IPv6 (SRv6) allows for a flexible definition of
end-to-end paths within various topologies by encoding paths as end-to-end paths within various topologies by encoding paths as
sequences of topological or functional sub-paths, called "segments". sequences of topological or functional sub-paths called "segments".
These segments are advertised by various protocols such as BGP, IS-IS These segments are advertised by various protocols such as BGP, IS-
and OSPFv3. IS, and OSPFv3.
This document defines extensions to BGP Link-state (BGP-LS) to This document defines extensions to BGP - Link State (BGP-LS) to
advertise SRv6 segments along with their behaviors and other advertise SRv6 segments along with their behaviors and other
attributes via BGP. The BGP-LS address-family solution for SRv6 attributes via BGP. The BGP-LS address-family solution for SRv6
described in this document is similar to BGP-LS for SR for the MPLS described in this document is similar to BGP-LS for SR for the MPLS
data-plane defined in a separate document. data plane, which is defined in RFC 9085.
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.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on 21 August 2023. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9514.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language
2. BGP-LS Extensions for SRv6 . . . . . . . . . . . . . . . . . 4 2. BGP-LS Extensions for SRv6
3. SRv6 Node Attributes . . . . . . . . . . . . . . . . . . . . 5 3. SRv6 Node Attributes
3.1. SRv6 Capabilities TLV . . . . . . . . . . . . . . . . . . 5 3.1. SRv6 Capabilities TLV
3.2. SRv6 Node MSD Types . . . . . . . . . . . . . . . . . . . 6 3.2. SRv6 Node MSD Types
4. SRv6 Link Attributes . . . . . . . . . . . . . . . . . . . . 7 4. SRv6 Link Attributes
4.1. SRv6 End.X SID TLV . . . . . . . . . . . . . . . . . . . 7 4.1. SRv6 End.X SID TLV
4.2. SRv6 LAN End.X SID TLV . . . . . . . . . . . . . . . . . 9 4.2. SRv6 LAN End.X SID TLV
4.3. SRv6 Link MSD Types . . . . . . . . . . . . . . . . . . . 11 4.3. SRv6 Link MSD Types
5. SRv6 Prefix Attributes . . . . . . . . . . . . . . . . . . . 11 5. SRv6 Prefix Attributes
5.1. SRv6 Locator TLV . . . . . . . . . . . . . . . . . . . . 11 5.1. SRv6 Locator TLV
6. SRv6 SID NLRI . . . . . . . . . . . . . . . . . . . . . . . . 13 6. SRv6 SID NLRI
6.1. SRv6 SID Information TLV . . . . . . . . . . . . . . . . 14 6.1. SRv6 SID Information TLV
7. SRv6 SID Attributes . . . . . . . . . . . . . . . . . . . . . 15 7. SRv6 SID Attributes
7.1. SRv6 Endpoint Behavior TLV . . . . . . . . . . . . . . . 15 7.1. SRv6 Endpoint Behavior TLV
7.2. SRv6 BGP Peer Node SID TLV . . . . . . . . . . . . . . . 16 7.2. SRv6 BGP PeerNode SID TLV
8. SRv6 SID Structure TLV . . . . . . . . . . . . . . . . . . . 18 8. SRv6 SID Structure TLV
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 9. IANA Considerations
9.1. BGP-LS NLRI-Types . . . . . . . . . . . . . . . . . . . . 19 9.1. BGP-LS NLRI Types
9.2. BGP-LS TLVs . . . . . . . . . . . . . . . . . . . . . . . 19 9.2. BGP-LS NLRI and Attribute TLVs
9.3. SRv6 BGP EPE SID Flags . . . . . . . . . . . . . . . . . 19 9.3. SRv6 BGP EPE SID Flags
10. Manageability Considerations . . . . . . . . . . . . . . . . 20 10. Manageability Considerations
11. Security Considerations . . . . . . . . . . . . . . . . . . . 21 11. Security Considerations
12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 21 12. References
13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 22 12.1. Normative References
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 22 12.2. Informative References
14.1. Normative References . . . . . . . . . . . . . . . . . . 22 Appendix A. Differences with BGP-EPE for SR-MPLS
14.2. Informative References . . . . . . . . . . . . . . . . . 24 Acknowledgements
Appendix A. Differences with BGP-EPE for SR-MPLS . . . . . . . . 24 Contributors
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25 Authors' Addresses
1. Introduction 1. Introduction
SRv6 refers to Segment Routing instantiated on the IPv6 data-plane SRv6 refers to Segment Routing instantiated on the IPv6 data plane
[RFC8402]. An SRv6 Segment is often referred to by its SRv6 Segment [RFC8402]. An SRv6 segment is often referred to by its SRv6 Segment
Identifier (SID). Identifier (SID).
The network programming paradigm [RFC8986] is central to SRv6. It The network programming paradigm [RFC8986] is central to SRv6. It
describes how different behaviors can be bound to SIDs and how a describes how different behaviors can be bound to SIDs and how a
network program can be expressed as a combination of SIDs. network program can be expressed as a combination of SIDs.
An SRv6-capable node maintains all the SRv6 segments explicitly An SRv6-capable node maintains all the SRv6 segments explicitly
instantiated locally. instantiated locally.
The IS-IS and OSPFv3 link-state routing protocols have been extended The IS-IS and OSPFv3 link-state routing protocols have been extended
to advertise some of these SRv6 SIDs and SRv6-related information to advertise some of these SRv6 SIDs and SRv6-related information
[I-D.ietf-lsr-isis-srv6-extensions], [RFC9352] [RFC9513]. Other SRv6 SIDs may be instantiated on a node
[I-D.ietf-lsr-ospfv3-srv6-extensions]. Other SRv6 SIDs may be via other mechanisms for topological or service functionalities.
instantiated on a node via other mechanisms for topological or
service functionalities.
The advertisement of SR related information along with the topology The advertisement of SR-related information along with the topology
for the MPLS data-plane instantiation (SR-MPLS) is specified in is specified in [RFC9085] for the MPLS data plane instantiation (SR-
[RFC9085] and for the BGP Egress Peer Engineering (EPE) is specified MPLS) and in [RFC9086] for BGP Egress Peer Engineering (EPE). On
in [RFC9086]. On similar lines, introducing the SRv6 related similar lines, introducing the SRv6-related information in BGP-LS
information in BGP-LS allows consumer applications that require allows consumer applications that require topological visibility to
topological visibility to also receive the SRv6 SIDs from nodes also receive the SRv6 SIDs from nodes across an IGP domain or even
across an IGP domain or even across Autonomous Systems (AS), as across Autonomous Systems (ASes) as required. This allows
required. This allows applications to leverage the SRv6 capabilities applications to leverage the SRv6 capabilities for network
for network programming. programming.
The identifying key of each Link-State object, namely a node, link, The identifying key of each link-state object, namely a node, link,
or prefix, is encoded in the Network-Layer Reachability Information or prefix, is encoded in the Network Layer Reachability Information
(NLRI) and the properties of the object are encoded in the BGP-LS (NLRI), and the properties of the object are encoded in the BGP-LS
Attribute [RFC7752]. Attribute [RFC7752].
This document describes extensions to BGP-LS to advertise the SRv6 This document describes extensions to BGP-LS to advertise the SRv6
SIDs and other SRv6 information from all the SRv6 capable nodes in SIDs and other SRv6 information from all the SRv6-capable nodes in
the IGP domain when sourced from link-state routing protocols and the IGP domain when sourced from link-state routing protocols and
directly from individual SRv6 capable nodes (e.g. when sourced from directly from individual SRv6-capable nodes (e.g., when sourced from
BGP for EPE). BGP for EPE).
1.1. Requirements Language 1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2. BGP-LS Extensions for SRv6 2. BGP-LS Extensions for SRv6
BGP-LS [RFC7752] defines the Node, Link, and Prefix Link-State BGP-LS [RFC7752] defines the Node, Link, and Prefix Link-State NLRI
Network Layer Reachability Information (NLRI) types and the types and the advertisement of their attributes via BGP.
advertisement of their attributes via BGP.
When a BGP-LS router advertises topology information that it sources When a BGP-LS router advertises topology information that it sources
from the underlying link-state routing protocol, then it derives the from the underlying link-state routing protocol, it derives the
corresponding SRv6 information from the SRv6 extensions for IS-IS corresponding SRv6 information from the SRv6 extensions for IS-IS
[I-D.ietf-lsr-isis-srv6-extensions] or OSPFv3 [RFC9352] or OSPFv3 [RFC9513] as applicable. In practice, this
[I-D.ietf-lsr-ospfv3-srv6-extensions], as applicable. In practice, derivation comprises a simple copy of the relevant fields from the
this derivation comprises a simple copy of the relevant fields from IS-IS or OSPFv3 TLV/sub-TLV into the fields of the corresponding BGP-
the IS-IS/OSPFv3 TLV/sub-TLV into the fields of the corresponding LS TLV/sub-TLV. When a BGP-LS router advertises topology information
BGP-LS TLV/sub-TLV. When a BGP-LS router advertises topology from the BGP routing protocol (e.g., for EPE) or advertises SRv6 SIDs
information from the BGP routing protocol (e.g., for EPE) or when it associated with a node using Direct as the Protocol-ID, it derives
advertises SRv6 SIDs associated with a node using Direct as the the SRv6 information from the local node. Such information is
Protocol-ID, then it derives the SRv6 information from the local advertised only on behalf of the local router, in contrast to the
node. Such information is advertised only on behalf of the local advertisement of information from all nodes of an IGP domain when
router, in contrast to the advertisement of information from all sourced from a link-state routing protocol.
nodes of an IGP domain when sourced from a link-state routing
protocol.
The SRv6 information pertaining to a node is advertised via the BGP- The SRv6 information pertaining to a node is advertised via the BGP-
LS Node NLRI and using the BGP-LS Attribute TLVs as follows: LS Node NLRI using the BGP-LS Attribute TLVs as follows:
* SRv6 Capabilities of the node are advertised via the SRv6 * The SRv6 capabilities of the node are advertised via the SRv6
Capabilities TLV (Section 3.1). Capabilities TLV (Section 3.1).
* Maximum SID Depth (MSD) types introduced for SRv6 are advertised * Maximum SID Depth (MSD) types introduced for SRv6 are advertised
(Section 3.2) using the Node MSD TLV specified in [RFC8814] (Section 3.2) using the Node MSD TLV specified in [RFC8814].
* Algorithm support for SRv6 is advertised via the SR-Algorithm TLV * Algorithm support for SRv6 is advertised via the SR-Algorithm TLV
specified in [RFC9085]. specified in [RFC9085].
The SRv6 information pertaining to a link is advertised via the BGP- The SRv6 information pertaining to a link is advertised via the BGP-
LS Link NLRI and using the BGP-LS Attribute TLVs as follows: LS Link NLRI using the BGP-LS Attribute TLVs as follows:
* SRv6 SID of the IGP Adjacency SID or the BGP EPE Peer Adjacency * The SRv6 SID of the IGP Adjacency SID or the BGP EPE Peer
SID [RFC8402] is advertised via the SRv6 End.X SID TLV introduced Adjacency SID [RFC8402] is advertised via the SRv6 End.X SID TLV
in this document (Section 4.1). introduced in this document (Section 4.1).
* SRv6 SID of the IGP Adjacency SID to a non-Designated Router (DR) * The SRv6 SID of the IGP Adjacency SID to a non-Designated Router
or non-Designated Intermediate-System (DIS) [RFC8402] is (DR) or non-Designated Intermediate System (DIS) [RFC8402] is
advertised via the SRv6 LAN End.X SID TLV introduced in this advertised via the SRv6 LAN End.X SID TLV introduced in this
document (Section 4.2). document (Section 4.2).
* MSD types introduced for SRv6 are advertised (Section 4.3) using * MSD types introduced for SRv6 are advertised (Section 4.3) using
the Link MSD TLV specified in [RFC8814]. the Link MSD TLV specified in [RFC8814].
The SRv6 information pertaining to a prefix is advertised via the The SRv6 information pertaining to a prefix is advertised via the
BGP-LS Prefix NLRI and using the BGP-LS Attribute TLVs as follows: BGP-LS Prefix NLRI using the BGP-LS Attribute TLVs as follows:
* SRv6 Locator is advertised via the SRv6 Locator TLV introduced in * The SRv6 Locator is advertised via the SRv6 Locator TLV introduced
this document (Section 5.1). in this document (Section 5.1).
* The attributes of the SRv6 Locator are advertised via the Prefix * The attributes of the SRv6 Locator are advertised via the Prefix
Attribute Flags TLV specified in [RFC9085]. Attribute Flags TLV specified in [RFC9085].
The SRv6 SIDs associated with the node are advertised using the BGP- The SRv6 SIDs associated with the node are advertised using the BGP-
LS SRv6 SID NLRI introduced in this document (Section 6). This LS SRv6 SID NLRI introduced in this document (Section 6). This
enables the BGP-LS encoding to scale to cover a potentially large set enables the BGP-LS encoding to scale to cover a potentially large set
of SRv6 SIDs instantiated on a node with the granularity of of SRv6 SIDs instantiated on a node with the granularity of
individual SIDs and without affecting the size and scalability of the individual SIDs and without affecting the size and scalability of the
BGP-LS updates. Had the SRv6 SIDs been advertised within the BGP-LS BGP-LS updates. If the SRv6 SIDs had been advertised within the BGP-
Link Attribute associated with the existing Node NLRI, the BGP-LS LS Link Attribute associated with the existing Node NLRI, the BGP-LS
update would have grown rather large with the increase in SRv6 SIDs update would have grown rather large with the increase in SRv6 SIDs
on the node and would have also required a large update message to be on the node and would have also required a large update message to be
generated for any change to even a single SRv6 SID. BGP-LS Attribute generated for any change, even a change to a single SRv6 SID. BGP-LS
TLVs for the SRv6 SID NLRI are introduced in this document as Attribute TLVs for the SRv6 SID NLRI are introduced in this document
follows: as follows:
* The endpoint behavior of the SRv6 SID is advertised via the SRv6 * The Endpoint behavior of the SRv6 SID is advertised via the SRv6
Endpoint Behavior TLV (Section 7.1). Endpoint Behavior TLV (Section 7.1).
* The BGP EPE Peer Node context for a PeerNode SID, and the Peer Set * The BGP EPE Peer Node context for a PeerNode SID and the Peer Set
context for a PeerSet SID [RFC8402] are advertised via the SRv6 context for a PeerSet SID [RFC8402] are advertised via the SRv6
BGP EPE Peer Node SID TLV (Section 7.2), BGP PeerNode SID TLV (Section 7.2).
Subsequent sections of this document specify the encoding and usage Subsequent sections of this document specify the encoding and usage
of these extensions. All the TLVs introduced follow the formats and of these extensions. All the TLVs introduced follow the formats and
common field definitions provided in [RFC7752]. common field definitions provided in [RFC7752].
3. SRv6 Node Attributes 3. SRv6 Node Attributes
The SRv6 attributes of a node are advertised using the BGP-LS The SRv6 attributes of a node are advertised using the BGP-LS
Attribute TLVs defined in this section and associated with the BGP-LS Attribute TLVs defined in this section and associated with the BGP-LS
Node NLRI. Node NLRI.
3.1. SRv6 Capabilities TLV 3.1. SRv6 Capabilities TLV
This BGP-LS Attribute TLV is used to announce the SRv6 capabilities This BGP-LS Attribute TLV is used to announce the SRv6 capabilities
of the node along with the BGP-LS Node NLRI and indicates the SRv6 of the node along with the BGP-LS Node NLRI and indicates the SRv6
support by the node. A single instance of this TLV MUST be included support by the node. A single instance of this TLV MUST be included
in the BGP-LS attribute for each SRv6 capable node. The IS-IS SRv6 in the BGP-LS Attribute for each SRv6-capable node. The IS-IS SRv6
Capabilities sub-TLV [I-D.ietf-lsr-isis-srv6-extensions] and the Capabilities sub-TLV [RFC9352] and the OSPFv3 SRv6 Capabilities TLV
OSPFv3 SRv6 Capabilities TLV [I-D.ietf-lsr-ospfv3-srv6-extensions] [RFC9513] that map to this BGP-LS TLV are specified with the ability
that map to this BGP-LS TLV are specified with the ability to carry to carry optional sub-sub-TLVs and sub-TLVs. However, no such
optional sub-sub-TLVs/sub-TLVs. However, no such extensions are extensions are currently defined. Moreover, the SRv6 Capabilities
currently defined. Moreover, the SRv6 Capabilities TLV defined below TLV defined below is not extensible. As a result, it is expected
is not extensible. As a result, it is expected that any extensions that any extensions will be introduced as top-level TLVs in the BGP-
will be introduced as top-level TLVs in the BGP-LS Attribute. LS Attribute. The SRv6 Capabilities TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Reserved | | Flags | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: SRv6 Capabilities TLV Format Figure 1: SRv6 Capabilities TLV Format
Where: where:
* Type: 1038 Type: 1038
* Length : 4. Length: 4
* Flags: 2 octet field. The flags are copied from the IS-IS SRv6 Flags: 2-octet field. The flags are copied from the IS-IS SRv6
Capabilities sub-TLV (section 2 of Capabilities sub-TLV (Section 2 of [RFC9352]) or from the OSPFv3
[I-D.ietf-lsr-isis-srv6-extensions]) or from the OSPFv3 SRv6 SRv6 Capabilities TLV (Section 2 of [RFC9513]) in the case of IS-
Capabilities TLV (section 2 of IS or OSPFv3, respectively.
[I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or
OSPFv3 respectively.
* Reserved: 2 octet that MUST be set to 0 when originated and Reserved: 2-octet field that MUST be set to 0 when originated and
ignored on receipt. ignored on receipt.
3.2. SRv6 Node MSD Types 3.2. SRv6 Node MSD Types
The Node MSD TLV [RFC8814] of the BGP-LS Attribute of the Node NLRI The Node MSD TLV [RFC8814] of the BGP-LS Attribute of the Node NLRI
is also used to advertise the limits and the Segment Routing Header is also used to advertise the limits and the Segment Routing Header
(SRH) [RFC8754] operations supported by the SRv6 capable node. The (SRH) [RFC8754] operations supported by the SRv6-capable node. The
SRv6 MSD Types specified in section 4 of SRv6 MSD types specified in Section 4 of [RFC9352] are also used with
[I-D.ietf-lsr-isis-srv6-extensions] are also used with the BGP-LS the BGP-LS Node MSD TLV, as these code points are shared between the
Node MSD TLV as these code points are shared between IS-IS, OSPF and IS-IS, OSPF, and BGP-LS protocols. The description and semantics of
BGP-LS protocols. The description and semantics of these new MSD- these new MSD types for BGP-LS are identical to those specified in
types for BGP-LS are identical as specified in [RFC9352].
[I-D.ietf-lsr-isis-srv6-extensions].
Each MSD-type is encoded in the BGP-LS Node MSD TLV as a one-octet Each MSD type is encoded in the BGP-LS Node MSD TLV as a one-octet
type followed by a one-octet value as derived from the IS-IS or type followed by a one-octet value as derived from the IS-IS or
OSPFv3 Node MSD advertisements as specified in [RFC8814]. OSPFv3 Node MSD advertisements specified in [RFC8814].
4. SRv6 Link Attributes 4. SRv6 Link Attributes
SRv6 attributes and SIDs associated with a link or adjacency are SRv6 attributes and SIDs associated with a link or adjacency are
advertised using the BGP-LS Attribute TLVs defined in this section advertised using the BGP-LS Attribute TLVs defined in this section
and associated with the BGP-LS Link NLRI. and associated with the BGP-LS Link NLRI.
4.1. SRv6 End.X SID TLV 4.1. SRv6 End.X SID TLV
The SRv6 End.X SID TLV is used to advertise the SRv6 SIDs associated The SRv6 End.X SID TLV is used to advertise the SRv6 SIDs associated
with an IGP Adjacency SID behavior that correspond to a point-to- with an IGP Adjacency SID behavior that correspond to a point-to-
point or point-to-multipoint link or adjacency of the node running point or point-to-multipoint link or adjacency of the node running
the IS-IS or OSPFv3 protocols. The information advertised via this the IS-IS or OSPFv3 protocols. The information advertised via this
TLV is derived from the IS-IS SRv6 End.X SID sub-TLV (section 8.1 of TLV is derived from the IS-IS SRv6 End.X SID sub-TLV (Section 8.1 of
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 End.X SID [RFC9352]) or the OSPFv3 SRv6 End.X SID sub-TLV (Section 9.1 of
sub-TLV (section 9.1 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) in the [RFC9513]) in the case of IS-IS or OSPFv3, respectively. This TLV
case of IS-IS or OSPFv3 respectively. This TLV can also be used to can also be used to advertise the SRv6 SID corresponding to the
advertise the SRv6 SID corresponding to the underlying layer-2 member underlying Layer 2 member links for a Layer 3 bundle interface as a
links for a layer-3 bundle interface as a sub-TLV of the L2 Bundle sub-TLV of the L2 Bundle Member Attribute TLV [RFC9085].
Member Attribute TLV [RFC9085].
This TLV is also used by BGP-LS to advertise the BGP EPE Peer This TLV is also used by BGP-LS to advertise the BGP EPE Peer
Adjacency SID for SRv6 on the same lines as specified for SR-MPLS in Adjacency SID for SRv6 on the same lines as specified for SR-MPLS in
[RFC9086]. The SRv6 SID for the BGP Peer Adjacency using End.X [RFC9086]. The SRv6 SID for the BGP Peer Adjacency using End.X
behaviors (viz. End.X, End.X with PSP, End.X with USP, and End.X behaviors (viz. End.X, End.X with PSP, End.X with USP, and End.X with
with PSP & USP) [RFC8986] indicates the cross-connect to a specific PSP & USP) [RFC8986] indicates the cross-connect to a specific Layer
layer-3 link to the specific BGP session peer (neighbor). 3 link to the specific BGP session peer (neighbor).
More than one instance of this TLV can be included in the BGP-LS More than one instance of this TLV (one for each SRv6 End.X SID) can
Attribute; one for each SRv6 End.X SID. be included in the BGP-LS Attribute.
The TLV has the following format: The TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Endpoint Behavior | Flags | Algorithm | | Endpoint Behavior | Flags | Algorithm |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Weight | Reserved | SID (16 octets) ... | | Weight | Reserved | SID (16 octets) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | Sub-TLVs (variable) . . . | SID (cont ...) | Sub-TLVs (variable) . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: SRv6 End.X TLV Format Figure 2: SRv6 End.X SID TLV Format
Where: where:
Type: 1106 Type: 1106
Length: variable Length: variable
Endpoint Behavior: 2 octet field. The Endpoint Behavior code Endpoint Behavior: 2-octet field. The Endpoint behavior code point
point for this SRv6 SID as defined in section 10.2 of [RFC8986]. for this SRv6 SID as defined in Section 10.2 of [RFC8986].
Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6 Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6
End.X SID sub-TLV (section 8.1 of End.X SID sub-TLV (Section 8.1 of [RFC9352]) or the OSPFv3 SRv6
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 End.X SID End.X SID sub-TLV (Section 9.1 of [RFC9513]) in the case of IS-IS
sub-TLV (section 9.1 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) in or OSPFv3, respectively. In the case of the BGP EPE Peer
the case of IS-IS or OSPFv3 respectively. In the case of BGP EPE Adjacency SID, the flags are as defined in Section 7.2.
Peer Adjacency SID, the flags are as defined in Section 7.2.
Algorithm: 1 octet field. Algorithm associated with the SID. Algorithm: 1-octet field. Algorithm associated with the SID.
Weight: 1 octet field. The value represents the weight of the SID Weight: 1-octet field. The value represents the weight of the SID
for the purpose of load balancing. The use of the weight is for the purpose of load balancing. The use of the weight is
defined in [RFC8402]. defined in [RFC8402].
Reserved: 1 octet field that MUST be set to 0 when originated and Reserved: 1-octet field that MUST be set to 0 when originated and
ignored on receipt. ignored on receipt.
SID: 16 octet field. This field encodes the advertised SRv6 SID SID: 16-octet field. This field encodes the advertised SRv6 SID as
as 128 bit value. a 128-bit value.
Sub-TLVs : Used to advertise sub-TLVs that provide additional Sub-TLVs: Used to advertise sub-TLVs that provide additional
attributes for the specific SRv6 SID. This document defines one attributes for the specific SRv6 SID. This document defines one
in Section 8. in Section 8.
4.2. SRv6 LAN End.X SID TLV 4.2. SRv6 LAN End.X SID TLV
For a LAN interface, an IGP node ordinarily announces only its For a LAN interface, an IGP node ordinarily announces only its
adjacency to the IS-IS pseudo-node (or the equivalent OSPF DR). The adjacency to the IS-IS pseudonode (or the equivalent OSPF DR). The
information advertised via this TLV is derived from the IS-IS SRv6 information advertised via this TLV is derived from the IS-IS SRv6
LAN End.X SID sub-TLV (section 8.2 of LAN End.X SID sub-TLV (Section 8.2 of [RFC9352]) or the OSPFv3 SRv6
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 LAN End.X LAN End.X SID sub-TLV (Section 9.2 of [RFC9513]) in the case of IS-IS
sub-TLV (section 9.2 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) in the or OSPFv3, respectively. The SRv6 LAN End.X SID TLV allows a node to
case of IS-IS or OSPFv3 respectively. The SRv6 LAN End.X SID TLV announce the SRv6 SID corresponding to its adjacencies to all other
allows a node to announce the SRv6 SID corresponding to its (i.e., non-DIS or non-DR) nodes attached to the LAN in a single
adjacencies to all other (i.e., non-DIS or non-DR) nodes attached to instance of the BGP-LS Link NLRI. Without this TLV, multiple BGP-LS
the LAN in a single instance of the BGP-LS Link NLRI. Without this Link NLRIs would need to be originated, one for each neighbor, to
TLV, multiple BGP-LS Link NLRIs would need to be originated, one for advertise the SRv6 End.X SID TLVs for those non-DIS/non-DR neighbors.
each neighbor, to advertise the SRv6 End.X SID TLVs for those non- The SRv6 SID for these IGP adjacencies using the End.X behaviors
DIS/non-DR neighbors. The SRv6 SID for these IGP adjacencies using (viz. End.X, End.X with PSP, End.X with USP, and End.X with PSP &
the End.X behaviors (viz. End.X, End.X with PSP, End.X with USP, and USP) [RFC8986] are advertised using the SRv6 LAN End.X SID TLV.
End.X with PSP & USP) [RFC8986] are advertised using the SRv6 LAN
End.X SID TLV.
More than one instance of this TLV can be included in the BGP-LS More than one instance of this TLV (one for each SRv6 LAN End.X SID)
Attribute; one for each SRv6 LAN End.X SID. can be included in the BGP-LS Attribute.
The BGP-LS IS-IS SRv6 LAN End.X SID and BGP-LS OSPFv3 SRv6 LAN End.X The BGP-LS IS-IS SRv6 LAN End.X SID and BGP-LS OSPFv3 SRv6 LAN End.X
SID TLVs have the following format: SID TLVs have the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Endpoint Behavior | Flags | Algorithm | | Endpoint Behavior | Flags | Algorithm |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Weight | Reserved | Neighbor ID - | | Weight | Reserved | Neighbor ID - |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| IS-IS System-ID (6 octets) or OSPFv3 Router-ID (4 octets) | | IS-IS System-ID (6 octets) or OSPFv3 Router-ID (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (16 octets) ... | | SID (16 octets) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (variable) . . . | Sub-TLVs (variable) . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: SRv6 LAN End.X SID TLV Format Figure 3: SRv6 LAN End.X SID TLV Format
Where: where:
* Type: 1107 in case of IS-IS and 1108 in case of OSPFv3 Type: 1107 for IS-IS and 1108 for OSPFv3
* Length: variable Length: variable
* Endpoint Behavior: 2 octet field. The Endpoint Behavior code Endpoint Behavior: 2-octet field. The Endpoint behavior code point
point for this SRv6 SID as defined in section 10.2 of [RFC8986]. for this SRv6 SID as defined in Section 10.2 of [RFC8986].
* Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6 Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6
LAN End.X SID sub-TLV (section 8.2 of LAN End.X SID sub-TLV (Section 8.2 of [RFC9352]) or the OSPFv3
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 LAN End.X SRv6 LAN End.X SID sub-TLV (Section 9.2 of [RFC9513]) in the case
SID sub-TLV (section 9.2 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) of IS-IS or OSPFv3, respectively.
in the case of IS-IS or OSPFv3 respectively.
* Algorithm: 1 octet field. Algorithm associated with the SID. Algorithm: 1-octet field. Algorithm associated with the SID.
* Weight: 1 octet field. The value represents the weight of the SID Weight: 1-octet field. The value represents the weight of the SID
for the purpose of load balancing. for the purpose of load balancing.
* Reserved: 1 octet field that MUST be set to 0 when originated and Reserved: 1-octet field that MUST be set to 0 when originated and
ignored on receipt. ignored on receipt.
* Neighbor ID : 6 octets of Neighbor System-ID in IS-IS SRv6 LAN Neighbor ID: 6 octets of Neighbor System-ID in the IS-IS SRv6 LAN
End.X SID TLV or 4 octets of Neighbor Router-id in the OSPFv3 SRv6 End.X SID TLV or 4 octets of Neighbor Router-ID in the OSPFv3 SRv6
LAN End.X SID TLV. LAN End.X SID TLV.
* SID: 16 octet field. This field encodes the advertised SRv6 SID SID: 16-octet field. This field encodes the advertised SRv6 SID as
as 128 bit value. a 128-bit value.
* Sub-TLVs : Used to advertise sub-TLVs that provide additional Sub-TLVs: Used to advertise sub-TLVs that provide additional
attributes for the specific SRv6 SID. This document defines one attributes for the specific SRv6 SID. This document defines one
in Section 8. in Section 8.
4.3. SRv6 Link MSD Types 4.3. SRv6 Link MSD Types
The Link MSD TLV [RFC8814] of the BGP-LS Attribute of the Link NLRI The Link MSD TLV [RFC8814] of the BGP-LS Attribute of the Link NLRI
is also used to advertise the limits and the SRH operations supported is also used to advertise the limits and the SRH operations supported
on the specific link by the SRv6 capable node. The SRv6 MSD Types on the specific link by the SRv6-capable node. The SRv6 MSD types
specified in section 4 of[I-D.ietf-lsr-isis-srv6-extensions] are also specified in Section 4 of [RFC9352] are also used with the BGP-LS
used with the BGP-LS Link MSD TLV as these code points are shared Link MSD TLV, as these code points are shared between the IS-IS,
between IS-IS, OSPF, and BGP-LS protocols. The description and OSPF, and BGP-LS protocols. The description and semantics of these
semantics of these new MSD types for BGP-LS are identical as new MSD types for BGP-LS are identical as specified in [RFC9352].
specified in [I-D.ietf-lsr-isis-srv6-extensions].
Each MSD-type is encoded in the BGP-LS Link MSD TLV as a one-octet Each MSD type is encoded in the BGP-LS Link MSD TLV as a one-octet
type followed by a one-octet value as derived from the IS-IS or type followed by a one-octet value as derived from the IS-IS or
OSPFv3 Link MSD advertisements as specified in [RFC8814]. OSPFv3 Link MSD advertisements specified in [RFC8814].
5. SRv6 Prefix Attributes 5. SRv6 Prefix Attributes
SRv6 attributes with an IPv6 prefix are advertised using the BGP-LS SRv6 attributes with an IPv6 prefix are advertised using the BGP-LS
Attribute TLVs defined in this section and associated with the BGP-LS Attribute TLVs defined in this section and associated with the BGP-LS
Prefix NLRI. Prefix NLRI.
5.1. SRv6 Locator TLV 5.1. SRv6 Locator TLV
As specified in [RFC8986], an SRv6 SID comprises Locator, Function As specified in [RFC8986], an SRv6 SID comprises locator, function,
and Argument parts. and argument parts.
A node is provisioned with one or more Locators supported by that A node is provisioned with one or more locators supported by that
node. Locators are covering prefixes for the set of SIDs provisioned node. Locators are covering prefixes for the set of SIDs provisioned
on that node. Each Locator is advertised as a BGP-LS Prefix NLRI on that node. Each locator is advertised as a BGP-LS Prefix NLRI
object along with the SRv6 Locator TLV in its BGP-LS Attribute. object along with the SRv6 Locator TLV in its BGP-LS Attribute.
The information advertised via this TLV is derived from the IS-IS The information advertised via this TLV is derived from the IS-IS
SRv6 Locator TLV (section 7.1 of [I-D.ietf-lsr-isis-srv6-extensions]) SRv6 Locator TLV (Section 7.1 of [RFC9352]) or the OSPFv3 SRv6
or the OSPFv3 SRv6 Locator TLV (section 7.1 of Locator TLV (Section 7.1 of [RFC9513]) in the case of IS-IS or
[I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or OSPFv3 OSPFv3, respectively.
respectively.
The IPv6 Prefix matching the Locator may be also advertised as prefix The IPv6 Prefix matching the locator may also be advertised as prefix
reachability by the underlying routing protocol. In this case, the reachability by the underlying routing protocol. In this case, the
Prefix NLRI would be also associated with the Prefix Metric TLV Prefix NLRI would also be associated with the Prefix Metric TLV
[RFC7752] that carries the routing metric for this prefix. A Prefix [RFC7752] that carries the routing metric for this prefix. A Prefix
NLRI, that has been advertised with a SRv6 Locator TLV, is also NLRI that has been advertised with a SRv6 Locator TLV is also
considered a normal routing prefix (i.e., prefix reachability) only considered a normal routing prefix (i.e., prefix reachability) only
when there is also an IGP metric TLV (TLV 1095) associated it. when there is also an IGP Metric TLV (TLV 1095) associated it.
Otherwise, it is considered only as an SRv6 Locator advertisement. Otherwise, it is only considered an SRv6 Locator advertisement.
The SRv6 Locator TLV has the following format: The SRv6 Locator TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Algorithm | Reserved | | Flags | Algorithm | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metric | | Metric |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (variable) . . . | Sub-TLVs (variable) . . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: SRv6 Locator TLV Format Figure 4: SRv6 Locator TLV Format
Where: where:
Type: 1162 Type: 1162
Length: variable Length: variable
Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6 Flags: 1 octet of flags. The flags are copied from the IS-IS SRv6
Locator TLV (section 7.1 of [I-D.ietf-lsr-isis-srv6-extensions]) Locator TLV (Section 7.1 of [RFC9352]) or the OSPFv3 SRv6 Locator
or the OSPFv3 SRv6 Locator TLV (section 7.1 of TLV (Section 7.1 of [RFC9513]) in the case of IS-IS or OSPFv3,
[I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or respectively.
OSPFv3 respectively.
Algorithm: 1 octet field. Algorithm associated with the SID. Algorithm: 1-octet field. Algorithm associated with the SID.
Reserved: 2 octet field. The value MUST be set to 0 when Reserved: 2-octet field. The value MUST be set to 0 when originated
originated and ignored on receipt. and ignored on receipt.
Metric: 4 octet field. The value of the metric for the Locator Metric: 4-octet field. The value of the metric for the locator
copied from the IS-IS SRv6 Locator TLV (section 7.1 of copied from the IS-IS SRv6 Locator TLV (Section 7.1 of [RFC9352])
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 Locator or the OSPFv3 SRv6 Locator TLV (Section 7.1 of [RFC9513]) in the
TLV (section 7.1 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or OSPFv3, respectively.
case of IS-IS or OSPFv3 respectively.
Sub-TLVs : Used to advertise sub-TLVs that provide additional Sub-TLVs: Used to advertise sub-TLVs that provide additional
attributes for the given SRv6 Locator. Currently, none are attributes for the given SRv6 Locator. Currently, none are
defined. defined.
6. SRv6 SID NLRI 6. SRv6 SID NLRI
The "Link-State NLRI" defined in [RFC7752] is extended to carry the The Link-State NLRI defined in [RFC7752] is extended to carry the
SRv6 SID information. SRv6 SID information.
A new "Link-State NLRI Type" is defined for SRv6 SID information as This document defines the following new Link-State NLRI type for SRv6
follows: SID information: SRv6 SID NLRI (type 6).
* Link-State NLRI Type: SRv6 SID NLRI (value 6).
The SRv6 SIDs associated with the node are advertised using the BGP- The SRv6 SIDs associated with the node are advertised using the BGP-
LS SRv6 SID NLRI. LS SRv6 SID NLRI.
The format of this new NLRI type is as shown in the following figure: This new NLRI type has the following format:
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
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
| Protocol-ID | | Protocol-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | | Identifier |
| (8 octets) | | (8 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Node Descriptors (variable) // | Local Node Descriptors (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SRv6 SID Descriptors (variable) // | SRv6 SID Descriptors (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: SRv6 SID NLRI Format Figure 5: SRv6 SID NLRI Format
Where: where:
* Protocol-ID: 1-octet field that specifies the information source Protocol-ID: 1-octet field that specifies the information source
protocol [RFC7752]. protocol [RFC7752].
* Identifier: 8 octet value as defined in [RFC7752]. Identifier: 8-octet value as defined in [RFC7752].
* Local Node Descriptors TLV: set of Node Descriptor TLVs for the Local Node Descriptors TLV: Set of Node Descriptor TLVs for the
local node, as defined in [RFC7752] for IGPs, direct, and static local node as defined in [RFC7752] for IGPs, the Direct Protocol-
configuration or as defined in [RFC9086] for BGP protocol. ID, and the Static configuration Protocol-ID or as defined in
[RFC9086] for BGP.
* SRv6 SID Descriptors: set of SRv6 SID Descriptor TLVs. This field SRv6 SID Descriptors: Set of SRv6 SID Descriptor TLVs. This field
MUST contain a single SRv6 SID Information TLV (Section 6.1) and MUST contain a single SRv6 SID Information TLV (Section 6.1) and
MAY contain the Multi-Topology Identifier TLV [RFC7752]. MAY contain the Multi-Topology Identifier TLV [RFC7752].
New TLVs for advertisement within the BGP-LS Attribute [RFC7752] are New TLVs for advertisement within the BGP-LS Attribute [RFC7752] are
defined in Section 7 to carry the attributes of an SRv6 SID. defined in Section 7 to carry the attributes of an SRv6 SID.
6.1. SRv6 SID Information TLV 6.1. SRv6 SID Information TLV
An SRv6 SID that is associated with the node and advertised using the An SRv6 SID that is associated with the node and advertised using the
SRv6 SID NLRI is encoded using the SRv6 SID Information TLV. SRv6 SID NLRI is encoded using the SRv6 SID Information TLV.
When advertising the SRv6 SIDs from the IGPs, the SID information is When advertising the SRv6 SIDs from the IGPs, the SID information is
derived from the IS-IS SRv6 End SID sub-TLV (section 7.2 of derived from the IS-IS SRv6 End SID sub-TLV (Section 7.2 of
[I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 End SID sub- [RFC9352]) or the OSPFv3 SRv6 End SID sub-TLV (Section 8 of
TLV (section 8 of [I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case [RFC9513]) in the case of IS-IS or OSPFv3, respectively.
of IS-IS or OSPFv3 respectively.
The TLV carries the SRv6 SIDs corresponding to the BGP PeerNode and The TLV carries the SRv6 SIDs corresponding to the BGP PeerNode and
PeerSet SID [RFC8402] when SRv6 BGP EPE functionality is enabled in PeerSet SIDs [RFC8402] when SRv6 BGP EPE functionality is enabled in
BGP. BGP.
The TLV has the following format: The TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (16 octets) ... | | SID (16 octets) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (cont ...) | | SID (cont ...) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: SRv6 SID Information TLV Format Figure 6: SRv6 SID Information TLV Format
Where: where:
Type: 518 Type: 518
Length: 16. Length: 16
SID: 16 octet field. This field encodes the advertised SRv6 SID SID: 16-octet field. This field encodes the advertised SRv6 SID as
as 128 bit value. a 128-bit value.
7. SRv6 SID Attributes 7. SRv6 SID Attributes
This section specifies the TLVs to be carried in the BGP Link State This section specifies the TLVs to be carried in the BGP Link State
Attribute associated with the BGP-LS SRv6 SID NLRI. Attribute associated with the BGP-LS SRv6 SID NLRI.
7.1. SRv6 Endpoint Behavior TLV 7.1. SRv6 Endpoint Behavior TLV
Each SRv6 SID instantiated on an SRv6 capable node has specific Each SRv6 SID instantiated on an SRv6-capable node has specific
instructions (called behavior) bound to it. [RFC8986] describes how instructions (called "behavior") bound to it. [RFC8986] describes
behaviors are bound to a SID and also defines the initial set of how behaviors are bound to a SID and also defines the initial set of
well-known behaviors. well-known behaviors.
The SRv6 Endpoint Behavior TLV is a mandatory TLV that MUST be The SRv6 Endpoint Behavior TLV is a mandatory TLV that MUST be
included in the BGP-LS Attribute associated with the BGP-LS SRv6 SID included in the BGP-LS Attribute associated with the BGP-LS SRv6 SID
NLRI. NLRI.
When advertising the SRv6 SIDs from the IGPs, the Endpoint behavior, When advertising the SRv6 SIDs from the IGPs, the Endpoint behavior,
Flags, and Algorithm are derived from the IS-IS SRv6 End SID sub-TLV Flags, and Algorithm are derived from the IS-IS SRv6 End SID sub-TLV
(section 7.2 of [I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 (Section 7.2 of [RFC9352]) or the OSPFv3 SRv6 End SID sub-TLV
SRv6 End SID sub-TLV (section 8 of (Section 8 of [RFC9513]) in the case of IS-IS or OSPFv3,
[I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or OSPFv3
respectively. respectively.
When advertising the SRv6 SIDs corresponding to the BGP EPE When advertising the SRv6 SIDs corresponding to the BGP EPE
functionality, the Endpoint Behavior corresponds to End.X and similar functionality, the Endpoint behavior corresponds to End.X and similar
behaviors. When advertising the SRv6 SIDs that are locally behaviors. When advertising the SRv6 SIDs that are locally
instantiated on the node using Direct as the Protoocl-ID, The instantiated on the node using Direct as the Protocol-ID, the
Endpoint Behavior corresponds to any SRv6 Endpoint Behavior Endpoint behavior corresponds to any SRv6 Endpoint behavior
associated with the node. Flags are currently not defined. The associated with the node. Flags are currently not defined. The
algorithm value MUST be 0 unless an algorithm is associated locally algorithm value MUST be 0 unless an algorithm is associated locally
with the SRv6 Locator from which the SID is allocated. with the SRv6 Locator from which the SID is allocated.
The TLV has the following format: The TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Endpoint Behavior | Flags | Algorithm | | Endpoint Behavior | Flags | Algorithm |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: SRv6 Endpoint Behavior TLV Figure 7: SRv6 Endpoint Behavior TLV
Where: where:
Type: 1250 Type: 1250
Length: 4.
Endpoint Behavior: 2 octet field. The Endpoint Behavior code Length: 4
point for this SRv6 SID. Support values are those from the "SRv6
Endpoint Behaviors" IANA registry (as established via section 10.2
of [RFC8986]).
Flags: 1 octet of flags. The flags map to the IS-IS or OSPFv3 Endpoint Behavior: 2-octet field. The Endpoint behavior code point
encodings when advertising SRv6 SIDs corresponding to IGPs. For for this SRv6 SID. Values are from the "SRv6 Endpoint Behaviors"
SRv6 SIDs corresponding to BGP EPE and when advertising SRv6 SID IANA registry (Section 10.2 of [RFC8986]).
using Direct Protocol-ID, none are defined currently and they MUST
be set to 0 when originated and ignored on receipt.
Algorithm: 1 octet field. Algorithm associated with the SID. Flags: 1 octet of flags. The flags map to the IS-IS or OSPFv3
encodings when advertising SRv6 SIDs corresponding to IGPs. No
flags are currently defined for SRv6 SIDs corresponding to BGP EPE
or for advertisement of a SRv6 SID using Direct as the Protocol-
ID. Undefined flags MUST be set to 0 when originating and ignored
on receipt.
7.2. SRv6 BGP Peer Node SID TLV Algorithm: 1-octet field. Algorithm associated with the SID.
The BGP PeerNode SID and PeerSet SID for SR-MPLS are specified in 7.2. SRv6 BGP PeerNode SID TLV
The BGP PeerNode and PeerSet SIDs for SR-MPLS are specified in
[RFC9086]. Similar Peer Node and Peer Set functionality can be [RFC9086]. Similar Peer Node and Peer Set functionality can be
realized with SRv6 using SIDs with END.X behavior. Refer to realized with SRv6 using SIDs with END.X behavior. Refer to
Appendix A for some differences between the signaling of these SIDs Appendix A for some differences between the signaling of these SIDs
in SR-MPLS and SRv6. The SRv6 BGP Peer Node SID TLV is a mandatory in SR-MPLS and SRv6. The SRv6 BGP PeerNode SID TLV is a mandatory
TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI advertised TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI advertised
by BGP for the EPE functionality. This TLV MUST be included along by BGP for the EPE functionality. This TLV MUST be included along
with SRv6 SIDs that are associated with the BGP PeerNode or PeerSet with SRv6 SIDs that are associated with the BGP PeerNode or PeerSet
functionality. functionality.
The TLV has the following format: The TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Weight | Reserved | | Flags | Weight | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer AS Number | | Peer AS Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer BGP Identifier | | Peer BGP Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: SRv6 BGP Peer Node SID TLV Format Figure 8: SRv6 BGP PeerNode SID TLV Format
Where: where:
* Type: 1251 Type: 1251
* Length: 12 Length: 12
* Flags: 1 octet of flags with the following definition:
0 1 2 3 4 5 6 7 Flags: 1 octet of flags with the following definitions:
+-+-+-+-+-+-+-+-+
|B|S|P| | 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
|B|S|P| |
+-+-+-+-+-+-+-+-+
Figure 9: SRv6 BGP EPE SID Flags Format Figure 9: SRv6 BGP EPE SID Flags Format
- B-Flag: Backup Flag. If set, the SID is eligible to be B-Flag: Backup Flag. If set, the SID is eligible to be protected
protected using fast reroute (FRR). The computation of the using Fast Reroute (FRR). The computation of the backup
backup forwarding path and its association with the forwarding forwarding path and its association with the forwarding entry
entry for the Peer BGP Identifier is implementation specific. for the Peer BGP Identifier are implementation specific.
- S-Flag: Set Flag. When set, the S-Flag indicates that the SID S-Flag: Set Flag. When set, the S-Flag indicates that the SID
refers to a set of BGP peering sessions (i.e., BGP Peer Set SID refers to a set of BGP peering sessions (i.e., BGP Peer Set SID
functionality) and therefore MAY be assigned to one or more functionality) and therefore MAY be assigned to one or more
End.X SIDs associated with BGP peer sessions. End.X SIDs associated with BGP peering sessions.
- P-Flag: Persistent Flag: When set, the P-Flag indicates that P-Flag: Persistent Flag. When set, the P-Flag indicates that the
the SID is persistently allocated, i.e., the value remains SID is persistently allocated, i.e., the value remains
consistent across router restart and/or session flap. consistent across router restart and/or session flap.
- Other bits are reserved for future use and MUST be set to 0 Other bits are reserved for future use and MUST be set to 0
when originated and ignored on receipt. when originated and ignored on receipt. The flags defined
above are also used with the SRv6 End.X SID TLV when
The flags defined above are also used with the SRv6 End.X SID TLV advertising the SRv6 BGP Peer Adjacency SID (Section 4.1).
when advertising SRv6 BGP Peer Adjacency SID (Section 4.1).
* Weight: 1 octet field. The value represents the weight of the SID Weight: 1-octet field. The value represents the weight of the SID
for the purpose of load balancing. The use of the weight is for the purpose of load balancing. The use of the weight is
defined in [RFC8402]. defined in [RFC8402].
* Reserved: 2 octet field. The value MUST be set to 0 when Reserved: 2-octet field. The value MUST be set to 0 when originated
originated and ignored on receipt. and ignored on receipt.
* Peer AS Number : 4 octets of BGP AS number of the peer router. Peer AS Number: 4 octets of the BGP AS number of the peer router.
* Peer BGP Identifier : 4 octets of the BGP Identifier (BGP Router- Peer BGP Identifier: 4 octets of the BGP Identifier (BGP Router-ID)
ID) of the peer router. of the peer router.
For an SRv6 BGP EPE Peer Node SID, one instance of this TLV is For an SRv6 BGP EPE PeerNode SID, one instance of this TLV is
associated with the SRv6 SID. For SRv6 BGP EPE Peer Set SID, associated with the SRv6 SID. For an SRv6 BGP EPE PeerSet SID,
multiple instances of this TLV (one for each peer in the “peer set”) multiple instances of this TLV (one for each peer in the "peer set")
are associated with the SRv6 SID and the S-Flag is SET. are associated with the SRv6 SID and the S-Flag is set.
8. SRv6 SID Structure TLV 8. SRv6 SID Structure TLV
The SRv6 SID Structure TLV is used to advertise the length of each The SRv6 SID Structure TLV is used to advertise the length of each
individual part of the SRv6 SID as defined in [RFC8986]. It is an individual part of the SRv6 SID as defined in [RFC8986]. It is an
optional TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI and optional TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI and
as a sub-TLV of the SRv6 End.X SID, IS-IS SRv6 LAN End.X SID, and as a sub-TLV of the SRv6 End.X SID, IS-IS SRv6 LAN End.X SID, and
OSPFv3 SRv6 LAN End.X SID TLVs. OSPFv3 SRv6 LAN End.X SID TLVs.
When advertising SRv6 SIDs from the IGPs, the SRv6 SID Structure When advertising SRv6 SIDs from the IGPs, the SRv6 SID Structure
information is derived from the IS-IS SRv6 SID Structure sub-sub-TLV information is derived from the IS-IS SRv6 SID Structure sub-sub-TLV
(section 9 of [I-D.ietf-lsr-isis-srv6-extensions]) or the OSPFv3 SRv6 (Section 9 of [RFC9352]) or the OSPFv3 SRv6 SID Structure sub-TLV
SID Structure sub-TLV (section 10 of (Section 10 of [RFC9513]) in the case of IS-IS or OSPFv3,
[I-D.ietf-lsr-ospfv3-srv6-extensions]) in the case of IS-IS or OSPFv3
respectively. respectively.
When advertising the SRv6 SIDs corresponding to the BGP EPE When advertising the SRv6 SIDs corresponding to the BGP EPE
functionality or for advertising SRv6 SIDs using Direct Protocol-ID, functionality or for advertising SRv6 SIDs using Direct as the
the SRv6 SID Structure information is derived from the locally Protocol-ID, the SRv6 SID Structure information is derived from the
provisioned SRv6 SID. locally provisioned SRv6 SID.
The TLV has the following format: The TLV has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LB Length | LN Length | Fun. Length | Arg. Length | | LB Length | LN Length | Fun. Length | Arg. Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: SRv6 SID Structure TLV Figure 10: SRv6 SID Structure TLV
Where: where:
Type: 1252 Type: 1252
Length: 4 Length: 4
LB Length: 1 octet field. SRv6 SID Locator Block length in bits. LB Length: 1-octet field. SRv6 SID Locator Block length in bits.
LN Length: 1 octet field. SRv6 SID Locator Node length in bits. LN Length: 1-octet field. SRv6 SID Locator Node length in bits.
Fun. Length: 1 octet field. SRv6 SID Function length in bits. Fun. Length: 1-octet field. SRv6 SID Function length in bits.
Arg. Length: 1 octet field. SRv6 SID Argument length in bits. Arg. Length: 1-octet field. SRv6 SID Argument length in bits.
The sum of the LB Length, LN Length, Func. Length, and Arg. Length The sum of the LB Length, LN Length, Fun. Length, and Arg. Length
MUST be less than or equal to 128. MUST be less than or equal to 128.
9. IANA Considerations 9. IANA Considerations
This document requests assigning code points from the IANA "Border Per this document, IANA has allocated code points in the "Border
Gateway Protocol - Link State (BGP-LS) Parameters" registry group as Gateway Protocol - Link State (BGP-LS) Parameters" registry group, as
described in the subsections below. described in the subsections below.
9.1. BGP-LS NLRI-Types 9.1. BGP-LS NLRI Types
The following code points have been assigned by IANA from the IANA has assigned the following code points in the "BGP-LS NLRI
registry called "BGP-LS NLRI-Types": Types" registry:
+------+----------------------------+---------------+ +======+===============+===========+
| Type | NLRI Type | Reference | | Type | NLRI Type | Reference |
+------+----------------------------+---------------+ +======+===============+===========+
| 6 | SRv6 SID NLRI | this document | | 6 | SRv6 SID NLRI | RFC 9514 |
+------+----------------------------+---------------+ +------+---------------+-----------+
Figure 11: SRv6 SID NLRI Type Code Point Table 1: Addition to BGP-LS NLRI
Types Registry
9.2. BGP-LS TLVs 9.2. BGP-LS NLRI and Attribute TLVs
The following TLV code points have been assigned by IANA from the IANA has assigned the following TLV code points in the "BGP-LS NLRI
registry called "BGP-LS Node Descriptor, Link Descriptor, Prefix and Attribute TLVs" registry:
Descriptor, and Attribute TLVs":
+----------+----------------------------------------+---------------+ +================+===========================+===========+
| TLV Code | Description | Value defined | | TLV Code Point | Description | Reference |
| Point | | in | +================+===========================+===========+
+----------+----------------------------------------+---------------+ | 518 | SRv6 SID Information | RFC 9514 |
| 518 | SRv6 SID Information | this document | +----------------+---------------------------+-----------+
| 1038 | SRv6 Capabilities | this document | | 1038 | SRv6 Capabilities | RFC 9514 |
| 1106 | SRv6 End.X SID | this document | +----------------+---------------------------+-----------+
| 1107 | IS-IS SRv6 LAN End.X SID | this document | | 1106 | SRv6 End.X SID | RFC 9514 |
| 1108 | OSPFv3 SRv6 LAN End.X SID | this document | +----------------+---------------------------+-----------+
| 1162 | SRv6 Locator | this document | | 1107 | IS-IS SRv6 LAN End.X SID | RFC 9514 |
| 1250 | SRv6 Endpoint Behavior | this document | +----------------+---------------------------+-----------+
| 1251 | SRv6 BGP Peer Node SID | this document | | 1108 | OSPFv3 SRv6 LAN End.X SID | RFC 9514 |
| 1252 | SRv6 SID Structure | this document | +----------------+---------------------------+-----------+
+----------+----------------------------------------+---------------+ | 1162 | SRv6 Locator | RFC 9514 |
+----------------+---------------------------+-----------+
| 1250 | SRv6 Endpoint Behavior | RFC 9514 |
+----------------+---------------------------+-----------+
| 1251 | SRv6 BGP PeerNode SID | RFC 9514 |
+----------------+---------------------------+-----------+
| 1252 | SRv6 SID Structure | RFC 9514 |
+----------------+---------------------------+-----------+
Figure 12: SRv6 BGP-LS Attribute TLV Code Points Table 2: Additions to BGP-LS NLRI and Attribute TLVs
Registry
9.3. SRv6 BGP EPE SID Flags 9.3. SRv6 BGP EPE SID Flags
This document requests the creation of a new registry called "SRv6 Per this document, IANA has created a new registry called "SRv6 BGP
BGP EPE SID Flags" under the "Border Gateway Protocol - Link State EPE SID Flags" under the "Border Gateway Protocol - Link State (BGP-
(BGP-LS) Parameters" registry group. The allocation policy of this LS) Parameters" registry group. The allocation policy of this
registry is "Standards Action" according to [RFC8126]. registry is "Standards Action" according to [RFC8126].
The following flags are defined: The initial contents of the registry are as follows:
Bit Description Reference +=====+==========================+===========+
--------------------------------------------------- | Bit | Description | Reference |
0 Backup Flag (B-Flag) This document +=====+==========================+===========+
1 Set Flag (S-Flag) This document | 0 | Backup Flag (B-Flag) | RFC 9514 |
2 Persistent Flag (P-Flag) This document +-----+--------------------------+-----------+
3-7 Unassigned | 1 | Set Flag (S-Flag) | RFC 9514 |
+-----+--------------------------+-----------+
| 2 | Persistent Flag (P-Flag) | RFC 9514 |
+-----+--------------------------+-----------+
| 3-7 | Unassigned | |
+-----+--------------------------+-----------+
Figure 13: SRv6 BGP EPE SID Flags Table 3: New SRv6 BGP EPE SID Flags Registry
10. Manageability Considerations 10. Manageability Considerations
This section is structured as recommended in [RFC5706]. This section is structured as recommended in [RFC5706].
The new protocol extensions introduced in this document augment the The new protocol extensions introduced in this document augment the
existing IGP topology information that is distributed via [RFC7752]. existing IGP topology information that is distributed via [RFC7752].
Procedures and protocol extensions defined in this document do not Procedures and protocol extensions defined in this document do not
affect the BGP protocol operations and management other than as affect the BGP protocol operations and management other than as
discussed in the Manageability Considerations section of [RFC7752]. discussed in Section 6 (Manageability Considerations) of [RFC7752].
Specifically, the malformed attribute tests for syntactic checks in Specifically, the malformed attribute tests for syntactic checks in
the Fault Management section of [RFC7752] now encompass the new BGP- Section 6.2.2 (Fault Management) of [RFC7752] now encompass the new
LS extensions defined in this document. The semantic or content BGP-LS extensions defined in this document. The semantic or content
checking for the TLVs specified in this document and their checking for the TLVs specified in this document and their
association with the BGP-LS NLRI types or their BGP-LS Attribute is association with the BGP-LS NLRI types or their BGP-LS Attribute are
left to the consumer of the BGP-LS information (e.g., an application left to the consumer of the BGP-LS information (e.g., an application
or a controller) and not the BGP protocol. or a controller) and not BGP.
The SR information introduced in BGP-LS by this specification may be The SR information introduced in BGP-LS by this specification may be
used by BGP-LS consumer applications like an SR path computation used by BGP-LS consumer applications like an SR Path Computation
engine (PCE) to learn the SRv6 capabilities of the nodes in the Engine (PCE) to learn the SRv6 capabilities of the nodes in the
topology and the mapping of SRv6 segments to those nodes. This can topology and the mapping of SRv6 segments to those nodes. This can
enable the SR PCE to perform path computations based on SR for enable the SR PCE to perform path computations based on SR for
traffic engineering use-cases and to steer traffic on paths different traffic-engineering use cases and to steer traffic on paths different
from the underlying IGP based distributed best path computation. from the underlying IGP-based distributed best path computation.
Errors in the encoding or decoding of the SRv6 information may result Errors in the encoding or decoding of the SRv6 information may result
in the unavailability of such information to the SR PCE or incorrect in the unavailability of such information to the SR PCE or incorrect
information being made available to it. This may result in the SR information being made available to it. This may result in the SR
PCE not being able to perform the desired SR-based optimization PCE not being able to perform the desired SR-based optimization
functionality or to perform it in an unexpected or inconsistent functionality or performing it in an unexpected or inconsistent
manner. The handling of such errors by applications like SR PCE may manner. The handling of such errors by applications like SR PCE may
be implementation-specific and out of the scope of this document. be implementation specific and out of the scope of this document.
The manageability considerations related to BGP EPE functionality are The manageability considerations related to BGP EPE functionality are
discussed in [RFC9086] in the context of SR-MPLS and they also apply discussed in [RFC9086] in the context of SR-MPLS; they also apply to
to this document in the context of SRv6. this document in the context of SRv6.
The extensions, specified in this document, do not introduce any new The extensions specified in this document do not introduce any new
configuration or monitoring aspects in BGP or BGP-LS other than as configuration or monitoring aspects in BGP or BGP-LS other than as
discussed in [RFC7752]. The manageability aspects of the underlying discussed in [RFC7752]. The manageability aspects of the underlying
SRv6 features are covered by [I-D.ietf-spring-srv6-yang]. SRv6 features are covered by [SRV6-YANG].
11. Security Considerations 11. Security Considerations
The new protocol extensions introduced in this document augment the The new protocol extensions introduced in this document augment the
existing IGP topology information that is distributed via [RFC7752]. existing IGP topology information that is distributed via [RFC7752].
The advertisement of the SRv6 link-state information defined in this The advertisement of the SRv6 link-state information defined in this
document presents a similar risk as associated with the existing set document presents a similar risk as associated with the existing
of link-state information as described in [RFC7752]. The Security link-state information as described in [RFC7752]. Section 8
Considerations section of [RFC7752] also applies to these extensions. (Security Considerations) of [RFC7752] also applies to these
The procedures and new TLVs defined in this document, by themselves, extensions. The procedures and new TLVs defined in this document, by
do not affect the BGP-LS security model discussed in [RFC7752]. themselves, do not affect the BGP-LS security model discussed in
[RFC7752].
The extensions introduced in this document are used to propagate IGP The extensions introduced in this document are used to propagate IGP-
defined information ([I-D.ietf-lsr-isis-srv6-extensions] and defined information [RFC9352] [RFC9513]. These extensions represent
[I-D.ietf-lsr-ospfv3-srv6-extensions]). These extensions represent
the advertisement of SRv6 information associated with the IGP node, the advertisement of SRv6 information associated with the IGP node,
link, and prefix. The IGP instances originating these TLVs are link, and prefix. The IGP instances originating these TLVs are
assumed to support all the required security and authentication assumed to support all the required security and authentication
mechanisms (as described in [I-D.ietf-lsr-isis-srv6-extensions] and mechanisms (as described in [RFC9352] and [RFC9513]).
[I-D.ietf-lsr-ospfv3-srv6-extensions]).
The security considerations related to BGP EPE functionality are The security considerations related to BGP EPE functionality are
discussed in [RFC9086] in the context of SR-MPLS and they also apply discussed in [RFC9086] in the context of SR-MPLS, and they also apply
to this document in the context of SRv6. to this document in the context of SRv6.
BGP-LS SRv6 extensions enable traffic engineering use-cases within BGP-LS SRv6 extensions enable traffic-engineering use cases within
the Segment Routing domain. SR operates within a trusted domain the SR domain. SR operates within a trusted domain [RFC8402], and
[RFC8402] and its security considerations also apply to BGP-LS its security considerations also apply to BGP-LS sessions when
sessions when carrying SR information. The SR traffic engineering carrying SR information. The SR traffic-engineering policies using
policies using the SIDs advertised via BGP-LS are expected to be used the SIDs advertised via BGP-LS are expected to be used entirely
entirely within this trusted SR domain (e.g., between multiple AS or within this trusted SR domain (e.g., between multiple AS or IGP
IGP domains within a single provider network). Therefore, precaution domains within a single provider network). Therefore, precaution is
is necessary to ensure that the link-state information (including necessary to ensure that the link-state information (including SRv6
SRv6 information) advertised via BGP-LS sessions is securely limited information) advertised via BGP-LS sessions is securely limited to
to consumers within this trusted SR domain. BGP peering sessions for consumers within this trusted SR domain. BGP peering sessions for
address-families other than Link-State may be set up to routers address families other than Link State may be set up to routers
outside the SR domain. The isolation of BGP-LS peering sessions is outside the SR domain. The isolation of BGP-LS peering sessions is
RECOMMENDED to ensure that BGP-LS topology information (including the RECOMMENDED to ensure that BGP-LS topology information (including the
newly added SR information) is not advertised to an external BGP newly added SR information) is not advertised to an external BGP
peering session outside the SR domain. peering session outside the SR domain.
12. Contributors 12. References
James Uttaro
AT&T
USA
Email: ju1738@att.com
Hani Elmalky
Ericsson
USA
Email: hani.elmalky@gmail.com
Arjun Sreekantiah
Individual
USA
Email: arjunhrs@gmail.com
Les Ginsberg
Cisco Systems
USA
Email: ginsberg@cisco.com
Shunwan Zhuang
Huawei
China
Email: zhuangshunwan@huawei.com
13. Acknowledgements
The authors would like to thank Peter Psenak, Arun Babu, Pablo
Camarillo, Francois Clad, Peng Shaofu, Cheng Li, Dhruv Dhody, Tom
Petch, and Dan Romascanu for their review of this document and their
comments. The authors would also like to thank Susan Hares for her
shepherd review and Adrian Farrel for his detailed Routing
Directorate review.
14. References
14.1. Normative References
[I-D.ietf-lsr-isis-srv6-extensions]
Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and
Z. Hu, "IS-IS Extensions to Support Segment Routing over
IPv6 Dataplane", Work in Progress, Internet-Draft, draft-
ietf-lsr-isis-srv6-extensions-19, 14 November 2022,
<https://www.ietf.org/archive/id/draft-ietf-lsr-isis-srv6-
extensions-19.txt>.
[I-D.ietf-lsr-ospfv3-srv6-extensions] 12.1. Normative References
Li, Z., Hu, Z., Talaulikar, K., and P. Psenak, "OSPFv3
Extensions for SRv6", Work in Progress, Internet-Draft,
draft-ietf-lsr-ospfv3-srv6-extensions-09, 14 January 2023,
<https://www.ietf.org/archive/id/draft-ietf-lsr-
ospfv3-srv6-extensions-09.txt>.
[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>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752, Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016, DOI 10.17487/RFC7752, March 2016,
skipping to change at page 24, line 17 skipping to change at line 1010
(BGP-LS) Extensions for Segment Routing", RFC 9085, (BGP-LS) Extensions for Segment Routing", RFC 9085,
DOI 10.17487/RFC9085, August 2021, DOI 10.17487/RFC9085, August 2021,
<https://www.rfc-editor.org/info/rfc9085>. <https://www.rfc-editor.org/info/rfc9085>.
[RFC9086] Previdi, S., Talaulikar, K., Ed., Filsfils, C., Patel, K., [RFC9086] Previdi, S., Talaulikar, K., Ed., Filsfils, C., Patel, K.,
Ray, S., and J. Dong, "Border Gateway Protocol - Link Ray, S., and J. Dong, "Border Gateway Protocol - Link
State (BGP-LS) Extensions for Segment Routing BGP Egress State (BGP-LS) Extensions for Segment Routing BGP Egress
Peer Engineering", RFC 9086, DOI 10.17487/RFC9086, August Peer Engineering", RFC 9086, DOI 10.17487/RFC9086, August
2021, <https://www.rfc-editor.org/info/rfc9086>. 2021, <https://www.rfc-editor.org/info/rfc9086>.
14.2. Informative References [RFC9352] Psenak, P., Ed., Filsfils, C., Bashandy, A., Decraene, B.,
and Z. Hu, "IS-IS Extensions to Support Segment Routing
over the IPv6 Data Plane", RFC 9352, DOI 10.17487/RFC9352,
February 2023, <https://www.rfc-editor.org/info/rfc9352>.
[I-D.ietf-spring-srv6-yang] [RFC9513] Li, Z., Hu, Z., Talaulikar, K., Ed., and P. Psenak,
Raza, S., Agarwal, S., Liu, X., Hu, Z., Hussain, I., Shah, "OSPFv3 Extensions for Segment Routing over IPv6 (SRv6)",
H. C., Voyer, D., Matsushima, S., Horiba, K., RFC 9513, DOI 10.17487/RFC9513, November 2023,
Rajamanickam, J., and A. Abdelsalam, "YANG Data Model for <https://www.rfc-editor.org/info/rfc9513>.
SRv6 Base and Static", Work in Progress, Internet-Draft,
draft-ietf-spring-srv6-yang-02, 23 September 2022, 12.2. Informative References
<https://www.ietf.org/archive/id/draft-ietf-spring-srv6-
yang-02.txt>.
[RFC5706] Harrington, D., "Guidelines for Considering Operations and [RFC5706] Harrington, D., "Guidelines for Considering Operations and
Management of New Protocols and Protocol Extensions", Management of New Protocols and Protocol Extensions",
RFC 5706, DOI 10.17487/RFC5706, November 2009, RFC 5706, DOI 10.17487/RFC5706, November 2009,
<https://www.rfc-editor.org/info/rfc5706>. <https://www.rfc-editor.org/info/rfc5706>.
[RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J., [RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020, (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
<https://www.rfc-editor.org/info/rfc8754>. <https://www.rfc-editor.org/info/rfc8754>.
[SRV6-YANG]
Raza, S., Agarwal, S., Liu, X., Hu, Z., Hussain, I., Shah,
H. C., Voyer, D., Matsushima, S., Horiba, K.,
Rajamanickam, J., and A. Abdelsalam, "YANG Data Model for
SRv6 Base and Static", Work in Progress, Internet-Draft,
draft-ietf-spring-srv6-yang-02, 23 September 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-spring-
srv6-yang-02>.
Appendix A. Differences with BGP-EPE for SR-MPLS Appendix A. Differences with BGP-EPE for SR-MPLS
The signaling of SRv6 SIDs corresponding to BGP-EPE functionality as The signaling of SRv6 SIDs corresponding to BGP-EPE functionality as
defined in this document differ from the signaling of SR-MPLS BGP-EPE defined in this document differs from the signaling of SR-MPLS BGP-
SIDs as specified in [RFC9086]. This section provides a high-level EPE SIDs as specified in [RFC9086]. This section provides a high-
overview of the same. level overview of the same.
There is no difference in the advertisement of the BGP Peer Adjacency There is no difference in the advertisement of the BGP Peer Adjacency
SID in both SR-MPLS and SRv6 and it is advertised as an attribute of SID in both SR-MPLS and SRv6, and it is advertised as an attribute of
the Link NLRI which identifies a specific Layer 3 interface on the the Link NLRI, which identifies a specific Layer 3 interface on the
BGP Speaker. The difference is in the advertisement of the BGP Peer BGP Speaker. The difference is in the advertisement of the BGP
Node and Peer Set SIDs. PeerNode and PeerSet SIDs.
In case of SR-MPLS, an additional Link NLRI is required to be In the case of SR-MPLS, an additional Link NLRI is required to be
advertised corresponding to each BGP Peering session on the node. advertised corresponding to each BGP peering session on the node.
Note that, this is not the same Link NLRI associated with the actual Note that this is not the same Link NLRI associated with the actual
layer 3 interface even when the peering is set up using the interface Layer 3 interface even when the peering is set up using the interface
IP addresses. These BGP-LS Link NLRIs are not really links in the IP addresses. These BGP-LS Link NLRIs are not really links in the
conventional link-state routing data model but instead identify BGP conventional link-state routing data model but instead identify BGP
peering sessions. The BGP Peer Node and/or Peer Set SIDs associated peering sessions. The BGP PeerNode and/or PeerSet SIDs associated
with that peering session are advertised as attributes associated with that peering session are advertised as attributes associated
with this peering Link NLRI. In the case of SRv6, each BGP Peer Node with this peering Link NLRI. In the case of SRv6, each BGP PeerNode
or Peer Set SID is considered to be associated with the BGP Speaker or PeerSet SID is considered to be associated with the BGP Speaker
node and is advertised using the BGP-LS SRv6 SID NLRI while the Node and is advertised using the BGP-LS SRv6 SID NLRI, while the
peering session information is advertised as attributes associated peering session information is advertised as attributes associated
with it. with it.
The advertisement of the BGP Peer Set SID for SR-MPLS is done by The advertisement of the BGP PeerSet SID for SR-MPLS is done by
including that SID as an attribute in all the Link NLRIs including that SID as an attribute in all the Link NLRIs
corresponding to the peering sessions that are part of the "set". corresponding to the peering sessions that are part of the "set".
The advertisement of the BGP Peer Set SID for SRv6 is advertised The advertisement of the BGP PeerSet SID for SRv6 is advertised using
using a single SRv6 SID NLRI and all the peers associated with that a single SRv6 SID NLRI, and all the peers associated with that "set"
"set" are indicated as attributes associated with the NLRI. are indicated as attributes associated with the NLRI.
Acknowledgements
The authors would like to thank Peter Psenak, Arun Babu, Pablo
Camarillo, Francois Clad, Peng Shaofu, Cheng Li, Dhruv Dhody, Tom
Petch, and Dan Romascanu for their review of this document and their
comments. The authors would also like to thank Susan Hares for her
shepherd review and Adrian Farrel for his detailed Routing Area
Directorate review.
Contributors
James Uttaro
AT&T
United States of America
Email: ju1738@att.com
Hani Elmalky
Ericsson
United States of America
Email: hani.elmalky@gmail.com
Arjun Sreekantiah
Individual
United States of America
Email: arjunhrs@gmail.com
Les Ginsberg
Cisco Systems
United States of America
Email: ginsberg@cisco.com
Shunwan Zhuang
Huawei
China
Email: zhuangshunwan@huawei.com
Authors' Addresses Authors' Addresses
Gaurav Dawra Gaurav Dawra
LinkedIn LinkedIn
United States of America United States of America
Email: gdawra.ietf@gmail.com Email: gdawra.ietf@gmail.com
Clarence Filsfils Clarence Filsfils
Cisco Systems Cisco Systems
Belgium Belgium
Email: cfilsfil@cisco.com Email: cfilsfil@cisco.com
Ketan Talaulikar (editor) Ketan Talaulikar (editor)
Cisco Systems Cisco Systems
India India
Email: ketant.ietf@gmail.com Email: ketant.ietf@gmail.com
Mach Chen Mach(Guoyi) Chen
Huawei Huawei
China China
Email: mach.chen@huawei.com Email: mach.chen@huawei.com
Daniel Bernier Daniel Bernier
Bell Canada Bell Canada
Canada Canada
Email: daniel.bernier@bell.ca Email: daniel.bernier@bell.ca
Bruno Decraene Bruno Decraene
Orange Orange
France France
Email: bruno.decraene@orange.com Email: bruno.decraene@orange.com
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