draft-ietf-idr-bgp-ls-segment-routing-ext-14.txt   draft-ietf-idr-bgp-ls-segment-routing-ext-15.txt 
Inter-Domain Routing S. Previdi Inter-Domain Routing S. Previdi
Internet-Draft Huawei Technologies Internet-Draft Huawei Technologies
Intended status: Standards Track K. Talaulikar, Ed. Intended status: Standards Track K. Talaulikar, Ed.
Expires: November 9, 2019 C. Filsfils Expires: December 1, 2019 C. Filsfils
Cisco Systems, Inc. Cisco Systems, Inc.
H. Gredler H. Gredler
RtBrick Inc. RtBrick Inc.
M. Chen M. Chen
Huawei Technologies Huawei Technologies
May 8, 2019 May 30, 2019
BGP Link-State extensions for Segment Routing BGP Link-State extensions for Segment Routing
draft-ietf-idr-bgp-ls-segment-routing-ext-14 draft-ietf-idr-bgp-ls-segment-routing-ext-15
Abstract Abstract
Segment Routing (SR) allows for a flexible definition of end-to-end Segment Routing (SR) allows for a flexible definition of end-to-end
paths by encoding paths as sequences of topological sub-paths, called paths by encoding paths as sequences of topological sub-paths, called
"segments". These segments are advertised by routing protocols e.g. "segments". These segments are advertised by routing protocols e.g.
by the link state routing protocols (IS-IS, OSPFv2 and OSPFv3) within by the link state routing protocols (IS-IS, OSPFv2 and OSPFv3) within
IGP topologies. IGP topologies.
This draft defines extensions to the BGP Link-state address-family in This document defines extensions to the BGP Link-state address-family
order to carry segment routing information via BGP. in order to carry segment routing information via BGP.
Requirements Language 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 BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
Status of This Memo Status of This Memo
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 9, 2019. This Internet-Draft will expire on December 1, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. BGP-LS Extensions for Segment Routing . . . . . . . . . . . . 4 2. BGP-LS Extensions for Segment Routing . . . . . . . . . . . . 4
2.1. Node Attributes TLVs . . . . . . . . . . . . . . . . . . 5 2.1. Node Attributes TLVs . . . . . . . . . . . . . . . . . . 5
2.1.1. SID/Label Sub-TLV . . . . . . . . . . . . . . . . . . 5 2.1.1. SID/Label Sub-TLV . . . . . . . . . . . . . . . . . . 5
2.1.2. SR Capabilities TLV . . . . . . . . . . . . . . . . . 6 2.1.2. SR Capabilities TLV . . . . . . . . . . . . . . . . . 6
2.1.3. SR Algorithm TLV . . . . . . . . . . . . . . . . . . 7 2.1.3. SR Algorithm TLV . . . . . . . . . . . . . . . . . . 8
2.1.4. SR Local Block TLV . . . . . . . . . . . . . . . . . 8 2.1.4. SR Local Block TLV . . . . . . . . . . . . . . . . . 8
2.1.5. SRMS Preference TLV . . . . . . . . . . . . . . . . . 10 2.1.5. SRMS Preference TLV . . . . . . . . . . . . . . . . . 10
2.2. Link Attribute TLVs . . . . . . . . . . . . . . . . . . . 10 2.2. Link Attribute TLVs . . . . . . . . . . . . . . . . . . . 11
2.2.1. Adjacency SID TLV . . . . . . . . . . . . . . . . . . 11 2.2.1. Adjacency SID TLV . . . . . . . . . . . . . . . . . . 11
2.2.2. LAN Adjacency SID TLV . . . . . . . . . . . . . . . . 12 2.2.2. LAN Adjacency SID TLV . . . . . . . . . . . . . . . . 12
2.2.3. L2 Bundle Member Attribute TLV . . . . . . . . . . . 14 2.2.3. L2 Bundle Member Attribute TLV . . . . . . . . . . . 14
2.3. Prefix Attribute TLVs . . . . . . . . . . . . . . . . . . 16 2.3. Prefix Attribute TLVs . . . . . . . . . . . . . . . . . . 16
2.3.1. Prefix SID TLV . . . . . . . . . . . . . . . . . . . 17 2.3.1. Prefix SID TLV . . . . . . . . . . . . . . . . . . . 17
2.3.2. Prefix Attribute Flags TLV . . . . . . . . . . . . . 18 2.3.2. Prefix Attribute Flags TLV . . . . . . . . . . . . . 18
2.3.3. Source Router Identifier (Source Router-ID) TLV . . . 19 2.3.3. Source Router Identifier (Source Router-ID) TLV . . . 19
2.3.4. Range TLV . . . . . . . . . . . . . . . . . . . . . . 19 2.3.4. Range TLV . . . . . . . . . . . . . . . . . . . . . . 19
2.4. Equivalent IS-IS Segment Routing TLVs/Sub-TLVs . . . . . 21 2.4. Equivalent IS-IS Segment Routing TLVs/Sub-TLVs . . . . . 21
2.5. Equivalent OSPFv2/OSPFv3 Segment Routing TLVs/Sub-TLVs . 22 2.5. Equivalent OSPFv2/OSPFv3 Segment Routing TLVs/Sub-TLVs . 22
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7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 28 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 28
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 28 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.1. Normative References . . . . . . . . . . . . . . . . . . 28 8.1. Normative References . . . . . . . . . . . . . . . . . . 28
8.2. Informative References . . . . . . . . . . . . . . . . . 30 8.2. Informative References . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 30 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 30
1. Introduction 1. Introduction
Segment Routing (SR) allows for a flexible definition of end-to-end Segment Routing (SR) allows for a flexible definition of end-to-end
paths by combining sub-paths called "segments". A segment can paths by combining sub-paths called "segments". A segment can
represent any instruction, topological or service-based. A segment represent any instruction; topological or service-based. A segment
can have a local semantic to an SR node or global within a domain. can have a local semantic to an SR node or global semantic within a
Within IGP topologies an SR path is encoded as a sequence of domain. Within IGP topologies, an SR path is encoded as a sequence
topological sub-paths, called "IGP segments". These segments are of topological sub-paths, called "IGP segments". These segments are
advertised by the link-state routing protocols (IS-IS, OSPFv2 and advertised by the link-state routing protocols (IS-IS, OSPFv2 and
OSPFv3). OSPFv3).
[RFC8402] defines the Link-State IGP segments - Prefix, Node, Anycast [RFC8402] defines the Link-State IGP segments - Prefix, Node, Anycast
and Adjacency segments. Prefix segments, by default, represent an and Adjacency segments. Prefix segments, by default, represent an
ECMP-aware shortest-path to a prefix, as per the state of the IGP ECMP-aware shortest-path to a prefix, as per the state of the IGP
topology. Adjacency segments represent a hop over a specific topology. Adjacency segments represent a hop over a specific
adjacency between two nodes in the IGP. A prefix segment is adjacency between two nodes in the IGP. A prefix segment is
typically a multi-hop path while an adjacency segment, in most of the typically a multi-hop path while an adjacency segment, in most of the
cases, is a one-hop path. Node and Anycast Segments are variations cases, is a one-hop path. Node and anycast segments are variations
of the Prefix Segment with their specific characteristics. of the prefix segment with their specific characteristics.
When Segment Routing is enabled in an IGP domain, segments are When Segment Routing is enabled in an IGP domain, segments are
advertised in the form of Segment Identifiers (SIDs). The IGP link- advertised in the form of Segment Identifiers (SIDs). The IGP link-
state routing protocols have been extended to advertise SIDs and state routing protocols have been extended to advertise SIDs and
other SR-related information. IGP extensions are described in: IS-IS other SR-related information. IGP extensions are described in: IS-IS
[I-D.ietf-isis-segment-routing-extensions], OSPFv2 [I-D.ietf-isis-segment-routing-extensions], OSPFv2
[I-D.ietf-ospf-segment-routing-extensions] and OSPFv3 [I-D.ietf-ospf-segment-routing-extensions] and OSPFv3
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. Using these [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. Using these
extensions, Segment Routing can be enabled within an IGP domain. extensions, Segment Routing can be enabled within an IGP domain.
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+-----------+ +-----------+ +-----------+ +-----------+ +-----------+ +-----------+
| BGP | | BGP | | BGP | | BGP | | BGP | | BGP |
| Speaker | | Speaker | . . . | Speaker | | Speaker | | Speaker | . . . | Speaker |
+-----------+ +-----------+ +-----------+ +-----------+ +-----------+ +-----------+
^ ^ ^ ^ ^ ^
| | | | | |
IGP IGP IGP IGP IGP IGP
Figure 1: Link State info collection Figure 1: Link State info collection
Figure 1 describes a typical deployment scenario. In each IGP area, Figure 1 denotes a typical deployment scenario. In each IGP area,
one or more nodes are configured with BGP-LS. These BGP speakers one or more nodes are configured with BGP-LS. These BGP speakers
form an IBGP mesh by connecting to one or more route-reflectors. form an IBGP mesh by connecting to one or more route-reflectors.
This way, all BGP speakers (specifically the route-reflectors) obtain This way, all BGP speakers (specifically the route-reflectors) obtain
Link-State information from all IGP areas (and from other ASes from Link-State information from all IGP areas (and from other ASes from
EBGP peers). An external component connects to the route-reflector EBGP peers). An external component connects to the route-reflector
to obtain this information (perhaps moderated by a policy regarding to obtain this information (perhaps moderated by a policy regarding
what information is or isn't advertised to the external component) as what information is or isn't advertised to the external component) as
described in [RFC7752]. described in [RFC7752].
This document describes extensions to BGP-LS to advertise the SR This document describes extensions to BGP-LS to advertise the SR
information. An external component (e.g., a controller) then can information. An external component (e.g., a controller) can collect
collect SR information from across an SR domain (as described in SR information from across an SR domain (as described in [RFC8402])
[RFC8402]) and construct the end-to-end path (with its associated and construct the end-to-end path (with its associated SIDs) that
SIDs) that need to be applied to an incoming packet to achieve the need to be applied to an incoming packet to achieve the desired end-
desired end-to-end forwarding. The SR domain may be comprised of a to-end forwarding. The SR domain may be comprised of a single AS or
single AS or multiple ASes. multiple ASes.
2. BGP-LS Extensions for Segment Routing 2. BGP-LS Extensions for Segment Routing
This document defines SR extensions to BGP-LS and specifies the TLVs This document defines SR extensions to BGP-LS and specifies the TLVs
and sub-TLVs for advertising SR information within the BGP-LS and sub-TLVs for advertising SR information within the BGP-LS
Attribute. Section 2.4 and Section 2.5 lists the equivalent TLVs and Attribute. Section 2.4 and Section 2.5 lists the equivalent TLVs and
sub-TLVs in IS-IS, OSPFv2 and OSPFv3 protocols. sub-TLVs in IS-IS, OSPFv2 and OSPFv3 protocols.
BGP-LS [RFC7752] defines the BGP-LS NLRI that can be a Node NLRI, a BGP-LS [RFC7752] defines the BGP-LS NLRI that can be a Node NLRI, a
Link NLRI or a Prefix NLRI. BGP-LS [RFC7752] defines the TLVs that Link NLRI or a Prefix NLRI. BGP-LS [RFC7752] defines the TLVs that
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[I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-segment-routing-extensions] and
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. [I-D.ietf-ospf-ospfv3-segment-routing-extensions].
The TLV and has the following format: The TLV and 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/Label (variable) | | SID/Label (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: SID/Label sub-TLV Format Figure 2: SID/Label sub-TLV Format
Where: Where:
Type: 1161 Type: 1161
Length: Either 3 or 4 depending whether the value is encoded as a Length: Variable. Either 3 or 4 depending whether the value is
label or an index/SID. encoded as a label or as an index/SID.
SID/Label: If length is set to 3, then the 20 rightmost bits SID/Label: If length is set to 3, then the 20 rightmost bits
represent a label (the total TLV size is 7). If length is set to represent a label (the total TLV size is 7) and the 4 leftmost
4, then the value represents a 32 bit SID (the total TLV size is bits are set to 0. If length is set to 4, then the value
8). represents a 32 bit SID (the total TLV size is 8).
2.1.2. SR Capabilities TLV 2.1.2. SR Capabilities TLV
The SR Capabilities TLV is used in order to advertise the node's SR The SR Capabilities TLV is used in order to advertise the node's SR
Capabilities including its Segment Routing Global Base (SRGB) Capabilities including its Segment Routing Global Base (SRGB)
range(s). In the case of IS-IS, the capabilities also include the range(s). In the case of IS-IS, the capabilities also include the
IPv4 and IPv6 support for the SR-MPLS forwarding plane. This IPv4 and IPv6 support for the SR-MPLS forwarding plane. This
information is derived from the protocol specific advertisements. information is derived from the protocol specific advertisements.
o IS-IS, as defined by the SR Capabilities sub-TLV in o IS-IS, as defined by the SR Capabilities sub-TLV in
skipping to change at page 7, line 14 skipping to change at page 7, line 14
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Range Size | | Range Size 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// SID/Label sub-TLV (variable) // | SID/Label sub-TLV 1 (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Range Size N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID/Label sub-TLV N (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: SR Capabilities TLV Format Figure 3: SR Capabilities TLV Format
Where: Where:
Type: 1034 Type: 1034
Length: Variable. Minimum length is 12. Length: Variable. Minimum length is 12.
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[I-D.ietf-ospf-segment-routing-extensions]. OSPFv3 leverages the [I-D.ietf-ospf-segment-routing-extensions]. OSPFv3 leverages the
same TLV as defined for OSPFv2. same TLV as defined for OSPFv2.
The SR Algorithm TLV has the following format: The SR Algorithm 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Algorithm 1 | Algorithm... | Algorithm N | | | Algorithm 1 | Algorithm... | Algorithm N |
+- -+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
Figure 4: SR Algorithm TLV Format Figure 4: SR Algorithm TLV Format
Where: Where:
Type: 1035 Type: 1035
Length: Variable. Minimum length is 1 and maximum can be 256. Length: Variable. Minimum length is 1 and maximum can be 256.
Algorithm: 1 octet identifying the algorithm. Algorithm: One or more fields of 1 octet each identifying the
algorithm.
2.1.4. SR Local Block TLV 2.1.4. SR Local Block TLV
The SR Local Block (SRLB) TLV contains the range(s) of labels the The SR Local Block (SRLB) TLV contains the range(s) of labels the
node has reserved for local SIDs. Local SIDs are used, e.g., in IGP node has reserved for local SIDs. Local SIDs are used, e.g., in IGP
(IS-IS, OSPF) for Adjacency-SIDs, and may also be allocated by (IS-IS, OSPF) for Adjacency-SIDs, and may also be allocated by
components other than IGP protocols. As an example, an application components other than IGP protocols. As an example, an application
or a controller may instruct a node to allocate a specific local SID. or a controller may instruct a node to allocate a specific local SID.
Therefore, in order for such applications or controllers to know the Therefore, in order for such applications or controllers to know the
range of local SIDs available, it is required that the node range of local SIDs available, it is required that the node
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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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Range Size | | Range Size 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// SID/Label sub-TLV (variable) // | SID/Label sub-TLV 1 (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Range Size N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID/Label sub-TLV N (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: SRLB TLV Format Figure 5: SRLB TLV Format
Where: Where:
Type: 1036 Type: 1036
Length: Variable. Minimum length is 12. Length: Variable. Minimum length is 12.
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+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
Figure 6: SRMS Preference TLV Format Figure 6: SRMS Preference TLV Format
Where: Where:
Type: 1037 Type: 1037
Length: 1. Length: 1.
Preference: 1 octet. Unsigned 8 bit SRMS preference. Preference: 1 octet carrying a unsigned 8 bit SRMS preference.
2.2. Link Attribute TLVs 2.2. Link Attribute TLVs
The following Link Attribute TLVs are are defined: The following Link Attribute TLVs are are defined:
+------+-----------------------+---------------+ +------+-----------------------+---------------+
| Type | Description | Section | | Type | Description | Section |
+------+-----------------------+---------------+ +------+-----------------------+---------------+
| 1099 | Adjacency SID TLV | Section 2.2.1 | | 1099 | Adjacency SID TLV | Section 2.2.1 |
| 1100 | LAN Adjacency SID TLV | Section 2.2.2 | | 1100 | LAN Adjacency SID TLV | Section 2.2.2 |
skipping to change at page 11, line 36 skipping to change at page 11, line 40
The Adjacency SID TLV has the following format: The Adjacency SID 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID/Label/Index (variable) | | SID/Label/Index (variable) //
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 7: Adjacency SID TLV Format Figure 7: Adjacency SID TLV Format
Where: Where:
Type: 1099 Type: 1099
Length: Variable, 7 or 8 depending on Label or Index encoding of Length: Variable. Either 7 or 8 depending on Label or Index
the SID encoding of the SID
Flags. 1 octet value which should be set as: Flags. 1 octet value which should be set as:
* IS-IS Adj-SID flags are defined in * IS-IS Adj-SID flags are defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2 Adj-SID flags are defined in * OSPFv2 Adj-SID flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3 Adj-SID flags are defined in * OSPFv3 Adj-SID flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
Weight: Weight used for load-balancing purposes. Weight: 1 octet carrying the weight used for load-balancing
purposes.
Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on
receipt. receipt.
SID/Index/Label: SID/Index/Label:
* IS-IS: Label or index value as defined in * IS-IS: Label or index value as defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2: Label or index value as defined in * OSPFv2: Label or index value as defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3: Label or index value as defined in * OSPFv3: Label or index value as defined in
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. [I-D.ietf-ospf-ospfv3-segment-routing-extensions].
The Flags and, as an extension, the SID/Index/Label fields of this The Flags and, as an extension, the SID/Index/Label fields of this
TLV need to be interpreted accordingly to the respective underlying TLV are interpreted according to the respective underlying IS-IS,
IS-IS, OSPFv2 or OSPFv3 protocol. The Protocol-ID of the BGP-LS Link OSPFv2 or OSPFv3 protocol. The Protocol-ID of the BGP-LS Link NLRI
NLRI should be used to determine the underlying protocol is used to determine the underlying protocol specification for
specification for parsing these fields. parsing these fields.
2.2.2. LAN Adjacency SID TLV 2.2.2. LAN Adjacency SID TLV
For a LAN, normally a node only announces its adjacency to the IS-IS For a LAN, normally a node only announces its adjacency to the IS-IS
pseudo-node (or the equivalent OSPF Designated and Backup Designated pseudo-node (or the equivalent OSPF Designated and Backup Designated
Routers). The LAN Adjacency Segment TLV allows a node to announce Routers). The LAN Adjacency Segment TLV allows a node to announce
adjacencies to all other nodes attached to the LAN in a single adjacencies to all other nodes attached to the LAN in a single
instance of the BGP-LS Link NLRI. Without this TLV, the instance of the BGP-LS Link NLRI. Without this TLV, the
corresponding BGP-LS link NLRI would need to be originated for each corresponding BGP-LS link NLRI would need to be originated for each
additional adjacency in order to advertise the SR TLVs for these additional adjacency in order to advertise the SR TLVs for these
skipping to change at page 13, line 20 skipping to change at page 13, line 24
| Flags | Weight | Reserved | | Flags | Weight | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OSPF Neighbor ID / IS-IS System-ID | | OSPF Neighbor ID / IS-IS System-ID |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID/Label/Index (variable) | | SID/Label/Index (variable) //
+---------------------------------------------------------------+ +---------------------------------------------------------------+
Figure 8: LAN Adjacency SID TLV Format Figure 8: LAN Adjacency SID TLV Format
Where: Where:
Type: 1100 Type: 1100
Length: Variable. For IS-IS it would be 13 or 14 depending on Length: Variable. For IS-IS it would be 13 or 14 depending on
Label or Index encoding of the SID. For OSPF it would be 11 or 12 Label or Index encoding of the SID. For OSPF it would be 11 or 12
skipping to change at page 13, line 44 skipping to change at page 13, line 48
* IS-IS LAN Adj-SID flags are defined in * IS-IS LAN Adj-SID flags are defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2 LAN Adj-SID flags are defined in * OSPFv2 LAN Adj-SID flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3 LAN Adj-SID flags are defined in * OSPFv3 LAN Adj-SID flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
Weight: Weight used for load-balancing purposes. Weight: 1 octet carrying the weight used for load-balancing
purposes.
Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on
receipt. receipt.
Neighbor ID: 6 octets for IS-IS for the System-ID and 4 octets for Neighbor ID: 6 octets for IS-IS for the System-ID and 4 octets for
OSPF for the OSPF Router-ID of the neighbor. OSPF for the OSPF Router-ID of the neighbor.
SID/Index/Label: SID/Index/Label:
* IS-IS: Label or index value as defined in * IS-IS: Label or index value as defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2: Label or index value as defined in * OSPFv2: Label or index value as defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3: Label or index value as defined in * OSPFv3: Label or index value as defined in
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. [I-D.ietf-ospf-ospfv3-segment-routing-extensions].
The Neighbor ID, Flags and, as an extension, the SID/Index/Label The Neighbor ID, Flags and, as an extension, the SID/Index/Label
fields of this TLV need to be interpreted accordingly to the fields of this TLV are interpreted according to the respective
respective underlying IS-IS, OSPFv2 or OSPFv3 protocol. The underlying IS-IS, OSPFv2 or OSPFv3 protocol. The Protocol-ID of the
Protocol-ID of the BGP-LS Link NLRI should be used to determine the BGP-LS Link NLRI is used to determine the underlying protocol
underlying protocol specification for parsing these fields. specification for parsing these fields.
2.2.3. L2 Bundle Member Attribute TLV 2.2.3. L2 Bundle Member Attribute TLV
The L2 Bundle Member Attribute TLV identifies an L2 Bundle Member The L2 Bundle Member Attribute TLV identifies an L2 Bundle Member
link which in turn is associated with a parent L3 link. The L3 link link which in turn is associated with a parent L3 link. The L3 link
is described by the Link NLRI defined in [RFC7752] and the L2 Bundle is described by the Link NLRI defined in [RFC7752] and the L2 Bundle
Member Attribute TLV is associated with the Link NLRI. The TLV MAY Member Attribute TLV is associated with the Link NLRI. The TLV MAY
include sub-TLVs which describe attributes associated with the bundle include sub-TLVs which describe attributes associated with the bundle
member. The identified bundle member represents a unidirectional member. The identified bundle member represents a unidirectional
path from the originating router to the neighbor specified in the path from the originating router to the neighbor specified in the
skipping to change at page 15, line 10 skipping to change at page 15, line 10
IS-IS [I-D.ietf-isis-l2bundles]. The equivalent functionality has IS-IS [I-D.ietf-isis-l2bundles]. The equivalent functionality has
not been specified as yet for OSPF. not been specified as yet for OSPF.
The L2 Bundle Member Attribute TLV has the following format: The L2 Bundle Member Attribute 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| L2 Bundle Member Descriptor | | L2 Bundle Member Descriptor |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Link attribute sub-TLVs(variable) // | Link attribute sub-TLVs(variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: L2 Bundle Member Attributes TLV Format Figure 9: L2 Bundle Member Attributes TLV Format
Where: Where:
Type: 1172 Type: 1172
Length: Variable. Length: Variable.
L2 Bundle Member Descriptor: A Link Local Identifier as defined in L2 Bundle Member Descriptor: 4 octets field that carries a Link
[RFC4202]. Local Identifier as defined in [RFC4202].
Link attributes for L2 Bundle Member Links are advertised as sub-TLVs Link attributes for L2 Bundle Member Links are advertised as sub-TLVs
of the L2 Bundle Member Attribute TLV. The sub-TLVs are identical to of the L2 Bundle Member Attribute TLV. The sub-TLVs are identical to
existing BGP-LS TLVs as identified in the table below. existing BGP-LS TLVs as identified in the table below.
+-------------+------------------------------------+----------------+ +-------------+------------------------------------+----------------+
| TLV Code | Description | Reference | | TLV Code | Description | Reference |
| Point | | Document | | Point | | Document |
+-------------+------------------------------------+----------------+ +-------------+------------------------------------+----------------+
| 1088 | Administrative group (color) | [RFC7752] | | 1088 | Administrative group (color) | [RFC7752] |
skipping to change at page 17, line 22 skipping to change at page 17, line 22
The Prefix SID TLV has the following format: The Prefix SID 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID/Index/Label (variable) | | SID/Index/Label (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: Prefix SID TLV Format Figure 10: Prefix SID TLV Format
Where: Where:
Type: 1158 Type: 1158
Length: Variable, 7 or 8 depending on Label or Index encoding of Length: Variable. 7 or 8 depending on Label or Index encoding of
the SID the SID
Flags: 1 octet value which should be set as: Flags: 1 octet value which should be set as:
* IS-IS Prefix SID flags are defined in * IS-IS Prefix SID flags are defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2 Prefix SID flags are defined in * OSPFv2 Prefix SID flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
skipping to change at page 18, line 15 skipping to change at page 18, line 15
* IS-IS: Label or index value as defined in * IS-IS: Label or index value as defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2: Label or index value as defined in * OSPFv2: Label or index value as defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3: Label or index value as defined in * OSPFv3: Label or index value as defined in
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. [I-D.ietf-ospf-ospfv3-segment-routing-extensions].
The Flags and, as an extension, the SID/Index/Label fields of this The Flags and, as an extension, the SID/Index/Label fields of this
TLV need to be interpreted accordingly to the respective underlying TLV are interpreted according to the respective underlying IS-IS,
IS-IS, OSPFv2 or OSPFv3 protocol. The Protocol-ID of the BGP-LS OSPFv2 or OSPFv3 protocol. The Protocol-ID of the BGP-LS Prefix NLRI
Prefix NLRI should be used to determine the underlying protocol is used to determine the underlying protocol specification for
specification for parsing these fields. parsing these fields.
2.3.2. Prefix Attribute Flags TLV 2.3.2. Prefix Attribute Flags TLV
The Prefix Attribute Flags TLV carries IPv4/IPv6 prefix attribute The Prefix Attribute Flags TLV carries IPv4/IPv6 prefix attribute
flags information. These flags are defined for OSPFv2 in [RFC7684], flags information. These flags are defined for OSPFv2 in [RFC7684],
for OSPFv3 in [RFC5340] and for IS-IS in [RFC7794]. for OSPFv3 in [RFC5340] and for IS-IS in [RFC7794].
The Prefix Attribute Flags TLV has the following format: The Prefix Attribute Flags 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 (variable) // | Flags (variable) //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: Prefix Attribute Flags TLV Format Figure 11: Prefix Attribute Flags TLV Format
Where: Where:
Type: 1170 Type: 1170
Length: variable. Length: Variable.
Flags: a variable length flag field (according to the length Flags: a variable length flag field (according to the length
field). Flags are routing protocol specific and are to be set as field). Flags are routing protocol specific and are to be set as
below: below:
* IS-IS flags correspond to the IPv4/IPv6 Extended Reachability * IS-IS flags correspond to the IPv4/IPv6 Extended Reachability
Attribute Flags defined in [RFC7794] Attribute Flags defined in [RFC7794]
* OSPFv2 flags correspond to the Flags field of the OSPFv2 * OSPFv2 flags correspond to the Flags field of the OSPFv2
Extended Prefix TLV defined in [RFC7684] Extended Prefix TLV defined in [RFC7684]
* OSPFv3 flags map to the Prefix Options field defined in * OSPFv3 flags map to the Prefix Options field defined in
[RFC5340] and extended via [RFC8362] [RFC5340] and extended via [RFC8362]
The Flags field of this TLV need to be interpreted accordingly to the The Flags field of this TLV is interpreted according to the
respective underlying IS-IS, OSPFv2 or OSPFv3 protocol. The respective underlying IS-IS, OSPFv2 or OSPFv3 protocol. The
Protocol-ID of the BGP-LS Prefix NLRI should be used to determine the Protocol-ID of the BGP-LS Prefix NLRI is used to determine the
underlying protocol specification for parsing these fields. underlying protocol specification for parsing this field.
2.3.3. Source Router Identifier (Source Router-ID) TLV 2.3.3. Source Router Identifier (Source Router-ID) TLV
The Source Router-ID TLV contains the IPv4 or IPv6 Router-ID of the The Source Router-ID TLV contains the IPv4 or IPv6 Router-ID of the
originator of the Prefix. For the IS-IS protocol this is derived originator of the Prefix. For the IS-IS protocol this is derived
from the IPv4/IPv6 Source Router ID sub-TLV as defined in [RFC7794]. from the IPv4/IPv6 Source Router ID sub-TLV as defined in [RFC7794].
For the OSPF protocol, this is derived from the Prefix Source Router- For the OSPF protocol, this is derived from the Prefix Source Router-
ID sub-TLV as defined in [I-D.ietf-lsr-ospf-prefix-originator]. ID sub-TLV as defined in [I-D.ietf-lsr-ospf-prefix-originator].
The Source Router-ID TLV has the following format: The Source Router-ID 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// 4 or 6 octet Router-ID // | 4 or 6 octet Router-ID //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 12: Source Router-ID TLV Format Figure 12: Source Router-ID TLV Format
Where: Where:
Type: 1171 Type: 1171
Length: 4 or 16 in case of IS-IS and 4 in case of OSPF. Length: Variable. 4 or 16 in case of IS-IS and 4 in case of OSPF.
Router-ID: the IPv4 or IPv6 Router-ID in case of IS-IS and the Router-ID: the IPv4 or IPv6 Router-ID in case of IS-IS and the
OSPF Router-ID in the case of OSPF. OSPF Router-ID in the case of OSPF.
2.3.4. Range TLV 2.3.4. Range TLV
The Range TLV is used in order to advertise a range of prefix-to-SID The Range TLV is used in order to advertise a range of prefix-to-SID
mappings as part of the Segment Routing Mapping Server (SRMS) mappings as part of the Segment Routing Mapping Server (SRMS)
functionality [I-D.ietf-spring-segment-routing-ldp-interop], as functionality [I-D.ietf-spring-segment-routing-ldp-interop], as
defined in the respective underlying IGP SR extensions defined in the respective underlying IGP SR extensions
[I-D.ietf-ospf-segment-routing-extensions], [I-D.ietf-ospf-segment-routing-extensions],
[I-D.ietf-ospf-ospfv3-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions] and
[I-D.ietf-isis-segment-routing-extensions]. The information [I-D.ietf-isis-segment-routing-extensions]. The information
advertised in the Range TLV is derived from the SID/Label Binding TLV advertised in the Range TLV is derived from the SID/Label Binding TLV
in the case of IS-IS and the OSPFv2/OSPFv3 Extended Prefix Range TLV in the case of IS-IS and the OSPFv2/OSPFv3 Extended Prefix Range TLV
in the case of OSPFv2/OSPFv3. in the case of OSPFv2/OSPFv3.
A Prefix NLRI, that been advertised with a Range TLV, is considered A Prefix NLRI, that been advertised with a Range TLV, is considered a
as a normal routing prefix (i.e. prefix reachability) unless there is normal routing prefix (i.e. prefix reachability) only when there is
also an IGP metric TLV (TLV 1095) attached to it. also an IGP metric TLV (TLV 1095) associated it. Otherwise, it is
considered only as the first prefix in the range for prefix-to-SID
mapping advertisement.
The format of the Range TLV is as follows: The format of the Range TLV is as follows:
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 | Range Size | | Flags | Reserved | Range Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// sub-TLVs // | sub-TLVs //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: Range TLV Format Figure 13: Range TLV Format
Where: Where:
Type: 1159 Type: 1159
Length: Variable, 11 or 12 depending on Label or Index encoding of Length: Variable. 11 or 12 depending on Label or Index encoding of
the SID the SID
Flags: 1 octet value which should be set as: Flags: 1 octet value which should be set as:
* IS-IS SID/Label Binding TLV flags are defined in * IS-IS SID/Label Binding TLV flags are defined in
[I-D.ietf-isis-segment-routing-extensions]. [I-D.ietf-isis-segment-routing-extensions].
* OSPFv2 OSPF Extended Prefix Range TLV flags are defined in * OSPFv2 OSPF Extended Prefix Range TLV flags are defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
* OSPFv3 Extended Prefix Range TLV flags are defined in * OSPFv3 Extended Prefix Range TLV flags are defined in
[I-D.ietf-ospf-ospfv3-segment-routing-extensions]. [I-D.ietf-ospf-ospfv3-segment-routing-extensions].
Reserved: 1 octet that SHOULD be set to 0 and MUST be ignored on Reserved: 1 octet that SHOULD be set to 0 and MUST be ignored on
receipt. receipt.
Range Size: 2 octets as defined in Range Size: 2 octets as defined in
[I-D.ietf-ospf-segment-routing-extensions]. [I-D.ietf-ospf-segment-routing-extensions].
The Flags field of this TLV need to be interpreted accordingly to the The Flags field of this TLV is interpreted according to the
respective underlying IS-IS, OSPFv2 or OSPFv3 protocol. The consumer respective underlying IS-IS, OSPFv2 or OSPFv3 protocol. The
of the BGP-LS interested in this TLV information MUST check the Protocol-ID of the BGP-LS Prefix NLRI is used to determine the
Protocol-ID of the BGP-LS Prefix NLRI and refer to the underlying underlying protocol specification for parsing this field.
protocol specification in order to parse this field.
The prefix-to-SID mappings are advertised using sub-TLVs as below: The prefix-to-SID mappings are advertised using sub-TLVs as below:
IS-IS: IS-IS:
SID/Label Range TLV SID/Label Range TLV
Prefix-SID sub-TLV Prefix-SID sub-TLV
OSPFv2/OSPFv3: OSPFv2/OSPFv3:
OSPFv2/OSPFv3 Extended Prefix Range TLV OSPFv2/OSPFv3 Extended Prefix Range TLV
Prefix SID sub-TLV Prefix SID sub-TLV
skipping to change at page 25, line 9 skipping to change at page 25, line 9
| | sub-TLV | | | | sub-TLV | |
| | (TBD) | | | | (TBD) | |
+-----------+------------+------------------------------------------+ +-----------+------------+------------------------------------------+
Table 7: OSPFv3 Segment Routing Extensions TLVs/Sub-TLVs Table 7: OSPFv3 Segment Routing Extensions TLVs/Sub-TLVs
3. IANA Considerations 3. IANA Considerations
Early allocation of codepoints has been done by IANA for this Early allocation of codepoints has been done by IANA for this
document from the registry "BGP-LS Node Descriptor, Link Descriptor, document from the registry "BGP-LS Node Descriptor, Link Descriptor,
Prefix Descriptor, and Attribute TLVs" based on Table 8. The column Prefix Descriptor, and Attribute TLVs" under the "BGP-LS Parameters"
"IS-IS TLV/Sub-TLV" defined in the registry does not require any registry based on Table 8. The column "IS-IS TLV/Sub-TLV" defined in
value and should be left empty. the registry does not require any value and should be left empty.
3.1. TLV/Sub-TLV Code Points Summary 3.1. TLV/Sub-TLV Code Points Summary
This section contains the global table of all TLVs/sub-TLVs defined This section contains the global table of all TLVs/sub-TLVs defined
in this document. in this document.
+----------------+-----------------------------+---------------+ +----------------+-----------------------------+---------------+
| TLV Code Point | Description | Reference | | TLV Code Point | Description | Reference |
+----------------+-----------------------------+---------------+ +----------------+-----------------------------+---------------+
| 1034 | SR Capabilities | Section 2.1.2 | | 1034 | SR Capabilities | Section 2.1.2 |
skipping to change at page 28, line 27 skipping to change at page 28, line 27
[I-D.ietf-isis-l2bundles] [I-D.ietf-isis-l2bundles]
Ginsberg, L., Bashandy, A., Filsfils, C., Nanduri, M., and Ginsberg, L., Bashandy, A., Filsfils, C., Nanduri, M., and
E. Aries, "Advertising L2 Bundle Member Link Attributes in E. Aries, "Advertising L2 Bundle Member Link Attributes in
IS-IS", draft-ietf-isis-l2bundles-07 (work in progress), IS-IS", draft-ietf-isis-l2bundles-07 (work in progress),
May 2017. May 2017.
[I-D.ietf-isis-segment-routing-extensions] [I-D.ietf-isis-segment-routing-extensions]
Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A.,
Gredler, H., and B. Decraene, "IS-IS Extensions for Gredler, H., and B. Decraene, "IS-IS Extensions for
Segment Routing", draft-ietf-isis-segment-routing- Segment Routing", draft-ietf-isis-segment-routing-
extensions-24 (work in progress), April 2019. extensions-25 (work in progress), May 2019.
[I-D.ietf-lsr-ospf-prefix-originator] [I-D.ietf-lsr-ospf-prefix-originator]
Wang, A., Lindem, A., Dong, J., Talaulikar, K., and P. Wang, A., Lindem, A., Dong, J., Talaulikar, K., and P.
Psenak, "OSPF Extension for Prefix Originator", draft- Psenak, "OSPF Extension for Prefix Originator", draft-
ietf-lsr-ospf-prefix-originator-00 (work in progress), ietf-lsr-ospf-prefix-originator-00 (work in progress),
February 2019. February 2019.
[I-D.ietf-ospf-ospfv3-segment-routing-extensions] [I-D.ietf-ospf-ospfv3-segment-routing-extensions]
Psenak, P. and S. Previdi, "OSPFv3 Extensions for Segment Psenak, P. and S. Previdi, "OSPFv3 Extensions for Segment
Routing", draft-ietf-ospf-ospfv3-segment-routing- Routing", draft-ietf-ospf-ospfv3-segment-routing-
 End of changes. 46 change blocks. 
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