< draft-ietf-idr-bgp-prefix-sid-04.txt   draft-ietf-idr-bgp-prefix-sid-05.txt >
IDR S. Previdi, Ed. IDR S. Previdi, Ed.
Internet-Draft C. Filsfils Internet-Draft C. Filsfils
Intended status: Standards Track A. Lindem Intended status: Standards Track A. Lindem
Expires: June 15, 2017 K. Patel Expires: October 22, 2017 A. Sreekantiah
A. Sreekantiah
Cisco Systems Cisco Systems
S. Ray
Unaffiliated
H. Gredler H. Gredler
RtBrick Inc. RtBrick Inc.
December 12, 2016 April 20, 2017
Segment Routing Prefix SID extensions for BGP Segment Routing Prefix SID extensions for BGP
draft-ietf-idr-bgp-prefix-sid-04 draft-ietf-idr-bgp-prefix-sid-05
Abstract Abstract
Segment Routing (SR) architecture allows a node to steer a packet Segment Routing (SR) architecture allows a node to steer a packet
flow through any topological path and service chain by leveraging flow through any topological path and service chain by leveraging
source routing. The ingress node prepends a SR header to a packet source routing. The ingress node prepends a SR header to a packet
containing a set of "segments". Each segment represents a containing a set of segment identifiers (SID). Each SID represents a
topological or a service-based instruction. Per-flow state is topological or a service-based instruction. Per-flow state is
maintained only at the ingress node of the SR domain. maintained only at the ingress node of the SR domain.
This document describes the BGP extension for announcing BGP Prefix This document describes the BGP extension for announcing BGP Prefix
Segment Identifier (BGP Prefix SID) information. Segment Identifier (BGP Prefix-SID) information.
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", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119] document are to be interpreted as described in RFC 2119 [RFC2119]
only when they appear in all upper case. They may also appear in only when they appear in all upper case. They may also appear in
lower or mixed case as English words, without any normative meaning. lower or mixed case as English words, without any normative meaning.
Status of This Memo Status of This Memo
skipping to change at page 2, line 6 skipping to change at page 2, line 4
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 22, 2017.
This Internet-Draft will expire on June 15, 2017.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2017 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
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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. Segment Routing Documents . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. BGP-Prefix-SID . . . . . . . . . . . . . . . . . . . . . . . 4
3. BGP-Prefix-SID . . . . . . . . . . . . . . . . . . . . . . . 4 2.1. MPLS BGP Prefix SID . . . . . . . . . . . . . . . . . . . 4
3.1. MPLS Prefix Segment . . . . . . . . . . . . . . . . . . . 4 2.2. IPv6 Prefix Segment . . . . . . . . . . . . . . . . . . . 5
3.2. IPv6 Prefix Segment . . . . . . . . . . . . . . . . . . . 5 3. BGP-Prefix-SID Attribute . . . . . . . . . . . . . . . . . . 5
4. BGP-Prefix-SID Attribute . . . . . . . . . . . . . . . . . . 5 3.1. Label-Index TLV . . . . . . . . . . . . . . . . . . . . . 6
4.1. Label-Index TLV . . . . . . . . . . . . . . . . . . . . . 6 3.2. IPv6 SID . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2. IPv6 SID . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3. Originator SRGB TLV . . . . . . . . . . . . . . . . . . . 7
4.3. Originator SRGB TLV . . . . . . . . . . . . . . . . . . . 8 4. Receiving BGP-Prefix-SID Attribute . . . . . . . . . . . . . 9
5. Receiving BGP-Prefix-SID Attribute . . . . . . . . . . . . . 9 4.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 9
5.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 9 4.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 10
5.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 10 5. Announcing BGP-Prefix-SID Attribute . . . . . . . . . . . . . 10
6. Announcing BGP-Prefix-SID Attribute . . . . . . . . . . . . . 10 5.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 10
6.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 11 5.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 11
6.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 11 6. Error Handling of BGP-Prefix-SID Attribute . . . . . . . . . 11
7. Error Handling of BGP-Prefix-SID Attribute . . . . . . . . . 12 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 8. Manageability Considerations . . . . . . . . . . . . . . . . 12
9. Security Considerations . . . . . . . . . . . . . . . . . . . 13 9. Security Considerations . . . . . . . . . . . . . . . . . . . 13
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13 10. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 13
11. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 13 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
12.1. Normative References . . . . . . . . . . . . . . . . . . 13 12.1. Normative References . . . . . . . . . . . . . . . . . . 14
12.2. Informative References . . . . . . . . . . . . . . . . . 13 12.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Segment Routing Documents 1. Introduction
The main references for this document are the SR architecture defined
in [I-D.ietf-spring-segment-routing] and the related use case
illustrated in [I-D.ietf-spring-segment-routing-msdc].
The Segment Routing Egress Peer Engineering architecture is described
in [I-D.ietf-spring-segment-routing-central-epe].
The Segment Routing Egress Peer Engineering BGPLS extensions are
described in [I-D.ietf-idr-bgpls-segment-routing-epe].
2. Introduction
Segment Routing (SR) architecture leverages the source routing Segment Routing (SR) architecture leverages the source routing
paradigm. A group of inter-connected nodes that use SR forms a SR paradigm. A group of inter-connected nodes that use SR forms a SR
domain. The ingress node of the SR domain prepends a SR header domain. A segment represents either a topological instruction such
containing "segments" to an incoming packet. Each segment represents as "go to prefix P following shortest path" or a service instruction
a topological instruction such as "go to prefix P following shortest (e.g.: "pass through deep packet inspection"). Other types of
path" or a service instruction (e.g.: "pass through deep packet segments may be defined in the future.
inspection"). By inserting the desired sequence of instructions, the
ingress node is able to steer a packet via any topological path and/
or service chain; per-flow state is maintained only at the ingress
node of the SR domain.
Each segment is identified by a Segment Identifier (SID). As A segment is identified through a Segment Identifier (SID).
described in [I-D.ietf-spring-segment-routing], when SR is applied to Typically, the ingress node of the SR domain prepends a SR header
the MPLS dataplane the SID consists of a label while when SR is containing segments identifiers (SIDs) to an incoming packet.
applied to the IPv6 dataplane the SID consists of an IPv6 prefix (see
[I-D.ietf-6man-segment-routing-header]).
A BGP-Prefix Segment (aka BGP-Prefix-SID), is a BGP segment attached As described in [I-D.ietf-spring-segment-routing], when SR is applied
to a BGP prefix. A BGP-Prefix-SID is always global within the SR/BGP to the MPLS dataplane ([I-D.ietf-spring-segment-routing-mpls]) the
domain and identifies an instruction to forward the packet over the SID consists of a label while when SR is applied to the IPv6
ECMP-aware best-path computed by BGP to the related prefix. The BGP- dataplane the SID consists of an IPv6 address.
Prefix-SID is the identifier of the BGP prefix segment.
This document describes the BGP extension to signal the BGP-Prefix- A BGP-Prefix Segment (and its BGP Prefix-SID), is a BGP segment
attached to a BGP prefix. A BGP Prefix-SID is always a global SID
([I-D.ietf-spring-segment-routing]) within the SR/BGP domain (i.e.,
the set of Autonomous Systems under a common administration and
control and where SR is used) and identifies an instruction to
forward the packet over the ECMP-aware best-path computed by BGP to
the related prefix. The BGP Prefix-SID is the identifier of the BGP
prefix segment. In this document we always refer to the BGP segment
as the BGP Prefix-SID.
This document describes the BGP extension to signal the BGP Prefix-
SID. Specifically, this document defines a new BGP attribute known SID. Specifically, this document defines a new BGP attribute known
as the BGP Prefix SID attribute and specifies the rules to originate, as the BGP Prefix-SID attribute and specifies the rules to originate,
receive and handle error conditions of the new attribute. receive and handle error conditions of the new attribute.
As described in [I-D.ietf-spring-segment-routing-msdc], the newly As described in [I-D.ietf-spring-segment-routing-msdc], the BGP
proposed BGP Prefix-SID attribute can be attached to prefixes from Prefix-SID attribute defined in this document can be attached to
AFI/SAFI: prefixes from AFI/SAFI:
Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]). Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]).
Multiprotocol BGP ([RFC4760]) unlabeled IPv6 Unicast. Multiprotocol BGP ([RFC4760]) unlabeled IPv6 Unicast.
[I-D.ietf-spring-segment-routing-msdc] describes use cases where the [I-D.ietf-spring-segment-routing-msdc] describes use cases where the
Prefix-SID is used for the above AFI/SAFI. Prefix-SID is used for the above AFI/SAFI.
3. BGP-Prefix-SID It has to be noted that:
The BGP-Prefix-SID attached to a BGP prefix P represents the o A BGP Prefix-SID MAY be global between domains when the
interconnected domains agree on the SID allocation scheme.
Alternatively, when interconnecting domains, the ASBRs of each
domain will have to handle the advertisement of unique SIDs. The
mechanisms for such interconnection are outside the scope of the
protocol extensions defined in this document.
o As described in [I-D.ietf-spring-segment-routing-msdc], a BGP
Prefix-SID MAY be attached to a prefix. In addition, each prefix
will likely have a different as_path attribute. This implies that
each prefix is advertised individually, reducing the ability to
pack BGP advertisements (when sharing common attributes).
2. BGP-Prefix-SID
The BGP Prefix-SID attached to a BGP prefix P represents the
instruction "go to Prefix P" along its BGP bestpath (potentially instruction "go to Prefix P" along its BGP bestpath (potentially
ECMP-enabled). ECMP-enabled).
3.1. MPLS Prefix Segment 2.1. MPLS BGP Prefix SID
The BGP Prefix Segment is realized on the MPLS dataplane in the The BGP Prefix-SID is realized on the MPLS dataplane
following way: ([I-D.ietf-spring-segment-routing-mpls]) in the following way:
As described in [I-D.ietf-spring-segment-routing-msdc] the As described in [I-D.ietf-spring-segment-routing-msdc] the
operator assigns a globally unique "index", L_I, to a locally operator assigns a globally unique "index", L_I, to a locally
sourced prefix of a BGP speaker N which is advertised to all other sourced prefix of a BGP speaker N which is advertised to all other
BGP speakers in the SR domain. BGP speakers in the SR domain.
According to [I-D.ietf-spring-segment-routing], each BGP speaker According to [I-D.ietf-spring-segment-routing], each BGP speaker
is configured with a label block called the Segment Routing Global is configured with a label block called the Segment Routing Global
Block (SRGB). While it is recommended to use the same SRGB across Block (SRGB). While [I-D.ietf-spring-segment-routing] recommends
all the nodes within the SR domain, the SRGB of a node is a local to use the same SRGB across all the nodes within the SR domain,
property and could be different on different speakers. The the SRGB of a node is a local property and could be different on
drawbacks of the use case where BGP speakers have different SRGBs different speakers. The drawbacks of the use case where BGP
are documented in [I-D.ietf-spring-segment-routing] and speakers have different SRGBs are documented in
[I-D.ietf-spring-segment-routing] and
[I-D.ietf-spring-segment-routing-msdc]. [I-D.ietf-spring-segment-routing-msdc].
If traffic-engineering within the SR domain is required, each node If traffic-engineering within the SR domain is required, each node
may also be required to advertise topological information and may also be required to advertise topological information and
Peering SID's for each of its links and peers. This informations Peering SID's for each of its links and peers. This information
is required in order to perform the explicit path computation and is required in order to perform the explicit path computation and
to express any explicit path into a list of segments. The to express any explicit path into a list of SIDs. The
advertisement of topological information and Peer segments is advertisement of topological information and Peer segments (Peer
assumed to be done through SIDs) is assumed to be done through
[I-D.ietf-idr-bgpls-segment-routing-epe]. [I-D.ietf-idr-bgpls-segment-routing-epe].
If the BGP speakers are not all configured with the same SRGB, and If the BGP speakers are not all configured with the same SRGB, and
if traffic-engineering within the SR domain is required, each node if traffic-engineering within the SR domain is required, each node
may be required to advertise its local SRGB in addition to the may be required to advertise its local SRGB in addition to the
topological information. topological information.
This documents assumes that BGP-LS is the preferred method for This documents assumes that BGP-LS is the preferred method for
collecting both topological, peer segments and SRGB information collecting both topological, peer segments (Peer SIDs) and SRGB
through [RFC7752], [I-D.ietf-idr-bgpls-segment-routing-epe] and information through [RFC7752],
[I-D.ietf-idr-bgpls-segment-routing-epe] and
[I-D.ietf-idr-bgp-ls-segment-routing-ext]. However, as an [I-D.ietf-idr-bgp-ls-segment-routing-ext]. However, as an
optional alternative for the advertisement of the local SRGB optional alternative for the advertisement of the local SRGB
without the topology nor the peer SID's, hence without without the topology nor the peer SID's, hence without
applicability for TE, the Originator SRGB TLV of the prefix-SID applicability for TE, the Originator SRGB TLV of the prefix-SID
attribute, is specified in Section 4.3 of this document. attribute, is specified in Section 3.3 of this document.
The index L_I is a 32 bit offset in the SRGB. Each BGP speaker As defined in [I-D.ietf-spring-segment-routing-mpls], the index
derives its local MPLS label, L, by adding L_I to the start value L_I is an offset in the SRGB. Each BGP speaker derives its local
of its own SRGB, and programs L in its MPLS dataplane as its MPLS label, L, by adding L_I to the start value of its own SRGB,
incoming/local label for the prefix. See Section 5.1 for more and programs L in its MPLS dataplane as its incoming/local label
for the prefix. It has to be noted that while SRGBs and SIDs are
advertised using 32 bit values, the derived label is to be
considered as the 20 right-most bits. See Section 4.1 for more
details. details.
The outgoing label for the prefix is found in the NLRI of the The outgoing label for the prefix is found in the NLRI of the
Multiprotocol BGP labeled IPv4/IPv6 Unicast prefix advertisement. Multiprotocol BGP labeled IPv4/IPv6 Unicast prefix advertisement.
The index L_I is only used as a hint to derive the local/incoming The index L_I is only used as a hint to derive the local/incoming
label. label.
Section 4.1 of this document specifies the Label-Index TLV of the Section 3.1 of this document specifies the Label-Index TLV of the
BGP Prefix-SID attribute; this TLV can be used to advertise the BGP Prefix-SID attribute; this TLV can be used to advertise the
label index of a given prefix. label index of a given prefix.
In order to advertise the label index of a given prefix P and, In order to advertise the label index of a given prefix P and,
optionally, the SRGB, a new extension to BGP is needed: the BGP optionally, the SRGB, a new extension to BGP is needed: the BGP
Prefix SID attribute. This extension is described in subsequent Prefix-SID attribute. This extension is described in subsequent
sections. sections.
3.2. IPv6 Prefix Segment 2.2. IPv6 Prefix Segment
As defined in [I-D.ietf-6man-segment-routing-header], and as
illustrated in [I-D.ietf-spring-segment-routing-msdc], when SR is
used over an IPv6 dataplane, the BGP Prefix Segment is instantiated
by an IPv6 prefix originated by the BGP speaker.
Each node advertises a globally unique IPv6 address representing
itself in the domain. This prefix (e.g.: its loopback interface
address) is advertised to all other BGP speakers in the SR domain.
Also, each node MUST advertise its support of Segment Routing for As illustrated in [I-D.ietf-spring-segment-routing-msdc], when SR is
IPv6 dataplane. This is realized using the flags contained in the used over an IPv6 dataplane, the BGP Prefix-SID consists of an IPv6
Prefix SID Attribute defined below. address assigned to the BGP speaker.
4. BGP-Prefix-SID Attribute 3. BGP-Prefix-SID Attribute
The BGP Prefix SID attribute is an optional, transitive BGP path The BGP Prefix-SID attribute is an optional, transitive BGP path
attribute. The attribute type code is to be assigned by IANA attribute. The attribute type code 40 has been assigned by IANA (see
(suggested value: 40). The value field of the BGP-Prefix-SID Section 7).
attribute has the following format:
The value field of the BGP Prefix SID attribute is defined here to be The BGP Prefix-SID attribute is defined here to be a set of elements
a set of elements encoded as "Type/Length/Value" (i.e., a set of encoded as "Type/Length/Value" (i.e., a set of TLVs). The following
TLVs). Following TLVs are defined: TLVs are defined:
o Label-Index TLV o Label-Index TLV
o IPv6 SID TLV o IPv6 SID TLV
o Originator SRGB TLV o Originator SRGB TLV
Label-Index and Originator SRGB TLVs are used only when SR is applied Label-Index and Originator SRGB TLVs are used only when SR is applied
to the MPLS dataplane. to the MPLS dataplane.
IPv6 SID TLV is used only when SR is applied to the IPv6 dataplane. IPv6 SID TLV is used only when SR is applied to the IPv6 dataplane.
4.1. Label-Index TLV 3.1. Label-Index TLV
The Label-Index TLV MUST be present in the Prefix-SID attribute The Label-Index TLV MUST be present in the Prefix-SID attribute
attached to Labeled IPv4/IPv6 unicast prefixes ([RFC3107]) and has attached to Labeled IPv4/IPv6 unicast prefixes ([RFC3107]) and has
the following format: 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 | RESERVED | | Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 6, line 42 skipping to change at page 6, line 42
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Index | | Label Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where: where:
o Type is 1. o Type is 1.
o Length: is 7, the total length of the value portion of the TLV. o Length: is 7, the total length of the value portion of the TLV.
o RESERVED: 8 bit field. SHOULD be 0 on transmission and MUST be o RESERVED: 8 bit field. MUST be clear on transmission an MUST be
ignored on reception. ignored at reception..
o Flags: 16 bits of flags. None are defined at this stage of the o Flags: 16 bits of flags. None is defined by this document. The
document. The flag field SHOULD be clear on transmission and MUST flag field MUST be clear on transmission and MUST be ignored at
be ignored at reception. reception.
o Label Index: 32 bit value representing the index value in the SRGB o Label Index: 32 bit value representing the index value in the SRGB
space. space.
4.2. IPv6 SID 3.2. IPv6 SID
The IPv6-SID TLV MUST be present in the Prefix-SID attribute attached The IPv6-SID TLV MAY be present in the Prefix-SID attribute attached
to MP-BGP unlabeled IPv6 unicast prefixes ([RFC4760]) and has the to MP-BGP unlabeled IPv6 unicast prefixes ([RFC4760]) and has the
following format: 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 | RESERVED | | Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | | RESERVED | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| |
| IPv6 SID (16 octets) |
| |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where: where:
o Type is 2. o Type is 2.
o Length: is 3, the total length of the value portion of the TLV. o Length: is 19, the total length of the value portion of the TLV.
o RESERVED: 8 bit field. SHOULD be 0 on transmission and MUST be
ignored on reception.
o Flags: 16 bits of flags defined as follow:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
* S flag: if set then it means that the BGP speaker attaching the o RESERVED: 24 bit field for future use. MUST be clear on
Prefix-SID Attribute to a prefix is capable of processing the transmission an MUST be ignored at reception.
IPv6 Segment Routing Header (SRH,
[I-D.ietf-6man-segment-routing-header]) for the segment
corresponding to the originated IPv6 prefix. The use case
leveraging the S flag is described in
[I-D.ietf-spring-segment-routing-msdc].
The other bits of the flag field SHOULD be clear on transmission o IPv6 SID: 16 octets.
an MUST be ignored at reception.
4.3. Originator SRGB TLV 3.3. Originator SRGB TLV
The Originator SRGB TLV is an optional TLV and has the following The Originator SRGB TLV is an optional TLV and has the following
format: 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 | Flags | | Type | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | | Flags |
skipping to change at page 8, line 37 skipping to change at page 8, line 32
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where: where:
o Type is 3. o Type is 3.
o Length is the total length of the value portion of the TLV: 2 + o Length is the total length of the value portion of the TLV: 2 +
multiple of 6. multiple of 6.
o Flags: 16 bits of flags. None are defined in this document. o Flags: 16 bits of flags. None is defined in this document. Flags
Flags SHOULD be clear on transmission an MUST be ignored at MUST be clear on transmission an MUST be ignored at reception.
reception.
o SRGB: 3 octets of base followed by 3 octets of range. Note that o SRGB: 3 octets of base followed by 3 octets of range. Note that
the SRGB field MAY appear multiple times. If the SRGB field the SRGB field MAY appear multiple times. If the SRGB field
appears multiple times, the SRGB consists of multiple ranges. The appears multiple times, the SRGB consists of multiple ranges.
meaning of an SRGB with multiple ranges is explained in
Section 3.2 ("SID/Label Range TLV") of
[I-D.ietf-ospf-segment-routing-extensions].
The Originator SRGB TLV contains the SRGB of the router originating The Originator SRGB TLV contains the SRGB of the node originating the
the prefix to which the BGP Prefix SID is attached and MUST be kept prefix to which the BGP Prefix-SID is attached and MUST be kept in
in the Prefix-SID Attribute unchanged during the propagation of the the Prefix-SID Attribute unchanged during the propagation of the BGP
BGP update. update.
The originator SRGB describes the SRGB of the node where the BGP The originator SRGB describes the SRGB of the node where the BGP
Prefix Segment end. It is used to build SRTE policies when different Prefix SID is attached. It is used to build segment routing policies
SRGB's are used in the fabric when different SRGB's are used in the fabric
([I-D.ietf-spring-segment-routing-msdc]). ([I-D.ietf-spring-segment-routing-msdc]).
The originator SRGB may only appear on Prefix-SID attribute attached The originator SRGB may only appear on Prefix-SID attribute attached
to prefixes of SAFI 4 (labeled unicast, [RFC3107]). to prefixes of SAFI 4 (labeled unicast, [RFC3107]).
5. Receiving BGP-Prefix-SID Attribute 4. Receiving BGP-Prefix-SID Attribute
A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP
neighbor residing outside the boundaries of the SR domain, SHOULD neighbor residing outside the boundaries of the SR domain, SHOULD
discard the attribute unless it is configured to accept the attribute discard the attribute unless it is configured to accept the attribute
from the EBGP neighbor. A BGP speaker MAY log an error for further from the EBGP neighbor. A BGP speaker MAY log an error for further
analysis when discarding an attribute. analysis when discarding an attribute.
5.1. MPLS Dataplane: Labeled Unicast 4.1. MPLS Dataplane: Labeled Unicast
A Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]) session A Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]) session
type is required. type is required.
A BGP speaker may be locally configured with an SRGB=[GB_S, GB_E]. A BGP speaker MAY be locally configured with an SRGB=[SRGB_Start,
The preferred method for deriving the SRGB is a matter of local SRGB_End]. The preferred method for deriving the SRGB is a matter of
router configuration. local node configuration.
Given a label index L_I, we call L = L_I + GB_S as the derived label. Given a label_index L_I, we call L = L_I + SRGB_Start as the derived
A BGP Prefix-SID attribute is called "unacceptable" for a speaker M label. A BGP Prefix-SID attribute is called "unacceptable" for a
if the derived label value L lies outside the SRGB configured on M. speaker M if the derived label value L lies outside the SRGB
Otherwise the Label Index attribute is called "acceptable" to speaker configured on M. Otherwise the Label Index attribute is called
M. "acceptable" to speaker M.
The mechanisms through which a given label_index value is assigned to The mechanisms through which a given label_index value is assigned to
a given prefix are outside the scope of this document. The label- a given prefix are outside the scope of this document. The label-
index value associated with a prefix is locally configured at the BGP index value associated with a prefix is locally configured at the BGP
router originating the prefix. node originating the prefix.
The Prefix-SID attribute MUST contain the Label-Index TLV and MAY The Prefix-SID attribute MUST contain the Label-Index TLV and MAY
contain the Originator SRGB TLV. A BGP Prefix-SID attribute received contain the Originator SRGB TLV. A BGP Prefix-SID attribute received
without a Label-Index TLV MUST be considered as "unacceptable" by the without a Label-Index TLV MUST be considered as "unacceptable" by the
receiving speaker. receiving speaker.
If multiple prefixes are received with the same label_index value,
all these prefixes MUST have their BGP Prefix-SID attribute
considered as "unacceptable" by the receiving speaker.
When a BGP speaker receives a path from a neighbor with an acceptable When a BGP speaker receives a path from a neighbor with an acceptable
BGP Prefix-SID attribute, it MUST program the derived label as the BGP Prefix-SID attribute, it MUST program the derived label as the
local label for the prefix in its MPLS dataplane. In case of any local label for the prefix in its MPLS dataplane. In case of any
error, a BGP speaker MUST resort to the error handling rules error, a BGP speaker MUST resort to the error handling rules
specified in Section 7. A BGP speaker MAY log an error for further specified in Section 6. A BGP speaker MAY log an error for further
analysis. analysis.
When a BGP speaker receives a path from a neighbor with an When a BGP speaker receives a path from a neighbor with an
unacceptable BGP Prefix-SID attribute or when a BGP speaker receives unacceptable BGP Prefix-SID attribute or when a BGP speaker receives
a path from a neighbor with a BGP-Prefix-SID attribute but is unable a path from a neighbor with a BGP Prefix-SID attribute but is unable
to process it (it does not have the capability or local policy to process it (it does not have the capability or local policy
disables the capability), it MUST treat the path as if it came disables the capability), it MUST treat the path as if it came
without a Prefix-SID attribute. For the purposes of local label without a Prefix-SID attribute. For the purposes of local label
allocation, a BGP speaker MUST assign a local (also called dynamic) allocation, a BGP speaker MUST assign a local (also called dynamic)
label (non-SRGB) for such a prefix as per classic Multiprotocol BGP label (non-SRGB) for such a prefix as per classic Multiprotocol BGP
labeled IPv4/IPv6 Unicast ([RFC3107]) operation. A BGP speaker MAY labeled IPv4/IPv6 Unicast ([RFC3107]) operation. A BGP speaker MAY
log an error for further analysis. log an error for further analysis.
The outgoing label is always programmed as per classic Multiprotocol The outgoing label is always programmed as per classic Multiprotocol
BGP labeled IPv4/IPv6 Unicast (RFC3107 [RFC3107]) operation. BGP labeled IPv4/IPv6 Unicast (RFC3107 [RFC3107]) operation.
Specifically, a BGP speaker receiving a prefix with a Prefix-SID Specifically, a BGP speaker receiving a prefix with a Prefix-SID
attribute and a label NLRI field of implicit-null from a neighbor attribute and a label NLRI field of implicit-null from a neighbor
MUST adhere to standard behavior and program its MPLS dataplane to MUST adhere to standard behavior and program its MPLS dataplane to
pop the top label when forwarding traffic to the prefix. The label pop the top label when forwarding traffic to the prefix. The label
NLRI defines the outbound label that MUST be used by the receiving NLRI defines the outbound label that MUST be used by the receiving
node. The Label Index gives a hint to the receiving node on which node. The Label Index gives the information to the receiving node on
local/incoming label the BGP speaker SHOULD use. which local/incoming label the BGP speaker SHOULD use.
5.2. IPv6 Dataplane 4.2. IPv6 Dataplane
When a SR IPv6 BGP speaker receives a IPv6 Unicast BGP Update with a When an SR IPv6 BGP speaker receives a IPv6 Unicast BGP Update with a
prefix having the BGP Prefix SID attribute attached, it checks prefix having the BGP Prefix-SID attribute attached, it checks
whether the IPv6 SID TLV is present and if the S-flag is set. If the whether the IPv6 SID TLV is present. If present, then the receiver
IPv6 SID TLV is present and if the S-flag is not set, then the assumes that the originator supports SR on the IPv6 dataplane.
Prefix-SID attribute MUST be considered as "unacceptable" by the
receiving speaker.
The Originator SRGB MUST be ignored on reception. The Originator SRGB MUST be ignored on reception.
A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP
neighbor residing outside the boundaries of the SR domain, SHOULD neighbor residing outside the boundaries of the SR domain, SHOULD
discard the attribute unless it is configured to accept the attribute discard the attribute unless it is configured to accept the attribute
from the EBGP neighbor. A BGP speaker MAY log an error for further from the EBGP neighbor. A BGP speaker MAY log an error for further
analysis when discarding an attribute. analysis when discarding an attribute.
6. Announcing BGP-Prefix-SID Attribute 5. Announcing BGP-Prefix-SID Attribute
The BGP Prefix-SID attribute MAY be attached to labeled BGP prefixes The BGP Prefix-SID attribute MAY be attached to labeled BGP prefixes
(IPv4/IPv6) [RFC3107]or to IPv6 prefixes [RFC4760]. In order to (IPv4/IPv6) [RFC3107] or to IPv6 prefixes [RFC4760]. In order to
prevent distribution of the BGP Prefix-SID attribute beyond its prevent distribution of the BGP Prefix-SID attribute beyond its
intended scope of applicability, attribute filtering MAY be deployed. intended scope of applicability, attribute filtering SHOULD be
deployed.
6.1. MPLS Dataplane: Labeled Unicast 5.1. MPLS Dataplane: Labeled Unicast
A BGP speaker that originates a prefix attaches the Prefix-SID A BGP speaker that originates a prefix attaches the Prefix-SID
attribute when it advertises the prefix to its neighbors via attribute when it advertises the prefix to its neighbors via
Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107])The value of Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]). The value
the Label-Index in the Label-Index TLV is determined by of the Label-Index in the Label-Index TLV is determined by
configuration. configuration.
A BGP speaker that originates a Prefix-SID attribute MAY optionally A BGP speaker that originates a Prefix-SID attribute MAY optionally
announce Originator SRGB TLV along with the mandatory Label-Index announce Originator SRGB TLV along with the mandatory Label-Index
TLV. The content of the Originator SRGB TLV is determined by the TLV. The content of the Originator SRGB TLV is determined by the
configuration. configuration.
Since the Label-index value must be unique within an SR domain, by Since the Label-index value must be unique within an SR domain, by
default an implementation SHOULD NOT advertise the BGP Prefix-SID default an implementation SHOULD NOT advertise the BGP Prefix-SID
attribute outside an Autonomous System unless it is explicitly attribute outside an Autonomous System unless it is explicitly
skipping to change at page 11, line 37 skipping to change at page 11, line 29
the speaker MAY attach a Prefix-SID to the path if configured to do the speaker MAY attach a Prefix-SID to the path if configured to do
so. The content of the TLVs present in the Prefix-SID is determined so. The content of the TLVs present in the Prefix-SID is determined
by the configuration. by the configuration.
In all cases, the label field of the advertised NLRI ([RFC3107], In all cases, the label field of the advertised NLRI ([RFC3107],
[RFC4364]) MUST be set to the local/incoming label programmed in the [RFC4364]) MUST be set to the local/incoming label programmed in the
MPLS dataplane for the given advertised prefix. If the prefix is MPLS dataplane for the given advertised prefix. If the prefix is
associated with one of the BGP speakers interfaces, this label is the associated with one of the BGP speakers interfaces, this label is the
usual MPLS label (such as the implicit or explicit NULL label). usual MPLS label (such as the implicit or explicit NULL label).
6.2. IPv6 Dataplane 5.2. IPv6 Dataplane
A BGP speaker that originates a prefix attaches the Prefix-SID A BGP speaker that originates an IPv6 prefix with the Prefix-SID
attribute when it advertises the prefix to its neighbors. The IPv6 attribute, MAY include the IPv6 SID TLV.
SID TLV MUST be present and the S-flag MUST be set.
A BGP speaker that advertises a path received from one of its A BGP speaker that advertises a path received from one of its
neighbors SHOULD advertise the Prefix-SID received with the path neighbors SHOULD advertise the Prefix-SID received with the path
without modification regardless of whether the Prefix-SID was without modification regardless of whether the Prefix-SID was
acceptable. If the path did not come with a Prefix-SID attribute, acceptable. If the path did not come with a Prefix-SID attribute,
the speaker MAY attach a Prefix-SID to the path if configured to do the speaker MAY attach a Prefix-SID to the path if configured to do
so. The IPv6-SID TLV MUST be present in the Prefix-SID and with the so.
S-flag set.
7. Error Handling of BGP-Prefix-SID Attribute 6. Error Handling of BGP-Prefix-SID Attribute
When a BGP Speaker receives a BGP Update message containing a When a BGP Speaker receives a BGP Update message containing a
malformed BGP Prefix-SID attribute, it MUST ignore the received BGP malformed BGP Prefix-SID attribute, it MUST ignore the received BGP
Prefix-SID attributes and not pass it to other BGP peers. This is Prefix-SID attributes and not pass it to other BGP peers. This is
equivalent to the -attribute discard- action specified in [RFC7606]. equivalent to the -attribute discard- action specified in [RFC7606].
When discarding an attribute, a BGP speaker MAY log an error for When discarding an attribute, a BGP speaker MAY log an error for
further analysis. further analysis.
If the BGP Prefix-SID attribute appears more than once in an BGP If the BGP Prefix-SID attribute appears more than once in an BGP
Update message, then, according to [RFC7606], all the occurrences of Update message, then, according to [RFC7606], all the occurrences of
the attribute other than the first one SHALL be discarded and the BGP the attribute other than the first one SHALL be discarded and the BGP
Update message shall continue to be processed. Update message SHALL continue to be processed.
When a BGP speaker receives an unacceptable Prefix-SID attribute, it When a BGP speaker receives an unacceptable Prefix-SID attribute, it
MAY log an error for further analysis. MAY log an error for further analysis.
8. IANA Considerations 7. IANA Considerations
This document defines a new BGP path attribute known as the BGP This document defines a new BGP path attribute known as the BGP
Prefix-SID attribute. This document requests IANA to assign a new Prefix-SID attribute. This document requests IANA to assign a new
attribute code type (suggested value: 40) for BGP the Prefix-SID attribute code type (suggested value: 40) for BGP the Prefix-SID
attribute from the BGP Path Attributes registry. attribute from the BGP Path Attributes registry.
Currently, IANA temporarily assigned the following: Currently, IANA temporarily assigned the following:
40 BGP Prefix-SID (TEMPORARY - registered 2015-09-30, expires 40 BGP Prefix-SID (TEMPORARY - registered 2015-09-30, expires
2016-09-30) [draft-ietf-idr-bgp-prefix-sid] 2016-09-30) [draft-ietf-idr-bgp-prefix-sid]
This document defines 3 new TLVs for BGP Prefix-SID attribute. These This document defines 3 new TLVs for BGP Prefix-SID attribute. These
TLVs need to be registered with IANA. We request IANA to create a TLVs need to be registered with IANA. We request IANA to create a
new registry for BGP Prefix-SID Attribute TLVs as follows: new registry for BGP Prefix-SID Attribute TLVs as follows:
Under "Border Gateway Protocol (BGP) Parameters" registry, "BGP Under "Border Gateway Protocol (BGP) Parameters" registry, "BGP
Prefix SID attribute Types" Reference: draft-ietf-idr-bgp-prefix-sid Prefix-SID attribute Types" Reference: draft-ietf-idr-bgp-prefix-sid
Registration Procedure(s): Values 1-254 First Come, First Served, Registration Procedure(s): Values 1-254 First Come, First Served,
Value 0 and 255 reserved Value 0 and 255 reserved
Value Type Reference Value Type Reference
0 Reserved this document 0 Reserved this document
1 Label-Index this document 1 Label-Index this document
2 IPv6 SID this document 2 IPv6 SID this document
3 Originator SRGB this document 3 Originator SRGB this document
4-254 Unassigned 4-254 Unassigned
255 Reserved this document 255 Reserved this document
8. Manageability Considerations
This document defines a new BGP attribute in order to address the use
case described in [I-D.ietf-spring-segment-routing-msdc]. It i
assumed that the new attribute (BGP Prefix-SID) advertisement is
controlled by the operator in order to:
o prevent undesired origination/advertisement of the BGP Prefix-SID
attribute. By default, a BGP Prefix-SID attribute SHOULD NOT be
originated and attached to a prefix. The operator MUST be capable
of explicitly enabling the BGP Prefix-SID origination.
o Prevent any undesired propagation of the BGP Prefix-SID attribute.
By default the BGP Prefix-SID is not advertised outside the
boundary of an AS. The propagation to other ASs MUST be
explicitly configured.
The deployment model described in
[I-D.ietf-spring-segment-routing-msdc] assumes multiple Autonomous
Systems (AS) under a common administration. The BGP Prefix-SID
advertisement is therefore applicable to inter-AS context while it is
confined within a single SR Domain.
9. Security Considerations 9. Security Considerations
This document introduces no new security considerations above and This document introduces a new BGP attribute (BGP Prefix-SID) which
beyond those already specified in [RFC4271] and [RFC3107]. inherits the security considerations expressed in: [RFC4271] and
[RFC3107].
10. Acknowledgements The BGP Prefix-SID attribute addresses the requirements introduced in
[I-D.ietf-spring-segment-routing-msdc] and It has to be noted, as
described in Section 8, that this document refer to a deployment
model where all nodes are under the same administration. In this
context, we assume that the operator doesn't want to leak outside of
the domain any information related to internal prefixes and topology.
The internal information includes the BGP Prefix-SID. In order to
prevent such leaking, the standard BGP mechanisms (filters) are
applied on the boundary of the domain.
The authors would like to thanks Satya Mohanty for his contribution 10. Contributors
to this document.
11. Change Log Keyur Patel
Arrcus, Inc.
US
Initial Version: Sep 21 2014 Email: Keyur@arrcus.com
Saikat Ray
Unaffiliated
US
Email: raysaikat@gmail.com
11. Acknowledgements
The authors would like to thanks Satya Mohanty for his contribution
to this document.
12. References 12. References
12.1. Normative References 12.1. Normative References
[I-D.ietf-spring-segment-routing]
Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
and R. Shakir, "Segment Routing Architecture", draft-ietf-
spring-segment-routing-11 (work in progress), February
2017.
[I-D.ietf-spring-segment-routing-mpls]
Filsfils, C., Previdi, S., Bashandy, A., Decraene, B.,
Litkowski, S., and R. Shakir, "Segment Routing with MPLS
data plane", draft-ietf-spring-segment-routing-mpls-08
(work in progress), March 2017.
[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,
<http://www.rfc-editor.org/info/rfc2119>. <http://www.rfc-editor.org/info/rfc2119>.
[RFC3107] Rekhter, Y. and E. Rosen, "Carrying Label Information in [RFC3107] Rekhter, Y. and E. Rosen, "Carrying Label Information in
BGP-4", RFC 3107, DOI 10.17487/RFC3107, May 2001, BGP-4", RFC 3107, DOI 10.17487/RFC3107, May 2001,
<http://www.rfc-editor.org/info/rfc3107>. <http://www.rfc-editor.org/info/rfc3107>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
skipping to change at page 14, line 5 skipping to change at page 14, line 46
Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
2006, <http://www.rfc-editor.org/info/rfc4364>. 2006, <http://www.rfc-editor.org/info/rfc4364>.
[RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K. [RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K.
Patel, "Revised Error Handling for BGP UPDATE Messages", Patel, "Revised Error Handling for BGP UPDATE Messages",
RFC 7606, DOI 10.17487/RFC7606, August 2015, RFC 7606, DOI 10.17487/RFC7606, August 2015,
<http://www.rfc-editor.org/info/rfc7606>. <http://www.rfc-editor.org/info/rfc7606>.
12.2. Informative References 12.2. Informative References
[I-D.ietf-6man-segment-routing-header]
Previdi, S., Filsfils, C., Field, B., Leung, I., Linkova,
J., Aries, E., Kosugi, T., Vyncke, E., and D. Lebrun,
"IPv6 Segment Routing Header (SRH)", draft-ietf-6man-
segment-routing-header-02 (work in progress), September
2016.
[I-D.ietf-idr-bgp-ls-segment-routing-ext] [I-D.ietf-idr-bgp-ls-segment-routing-ext]
Previdi, S., Psenak, P., Filsfils, C., Gredler, H., Chen, Previdi, S., Psenak, P., Filsfils, C., Gredler, H., Chen,
M., and j. jefftant@gmail.com, "BGP Link-State extensions M., and j. jefftant@gmail.com, "BGP Link-State extensions
for Segment Routing", draft-ietf-idr-bgp-ls-segment- for Segment Routing", draft-ietf-idr-bgp-ls-segment-
routing-ext-00 (work in progress), November 2016. routing-ext-01 (work in progress), February 2017.
[I-D.ietf-idr-bgpls-segment-routing-epe] [I-D.ietf-idr-bgpls-segment-routing-epe]
Previdi, S., Filsfils, C., Ray, S., Patel, K., Dong, J., Previdi, S., Filsfils, C., Patel, K., Ray, S., Dong, J.,
and M. Chen, "Segment Routing BGP Egress Peer Engineering and M. Chen, "Segment Routing BGP Egress Peer Engineering
BGP-LS Extensions", draft-ietf-idr-bgpls-segment-routing- BGP-LS Extensions", draft-ietf-idr-bgpls-segment-routing-
epe-06 (work in progress), November 2016. epe-11 (work in progress), March 2017.
[I-D.ietf-ospf-segment-routing-extensions]
Psenak, P., Previdi, S., Filsfils, C., Gredler, H.,
Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", draft-ietf-ospf-segment-
routing-extensions-10 (work in progress), October 2016.
[I-D.ietf-spring-segment-routing]
Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
and R. Shakir, "Segment Routing Architecture", draft-ietf-
spring-segment-routing-10 (work in progress), November
2016.
[I-D.ietf-spring-segment-routing-central-epe]
Filsfils, C., Previdi, S., Aries, E., and D. Afanasiev,
"Segment Routing Centralized BGP Peer Engineering", draft-
ietf-spring-segment-routing-central-epe-03 (work in
progress), November 2016.
[I-D.ietf-spring-segment-routing-msdc] [I-D.ietf-spring-segment-routing-msdc]
Filsfils, C., Previdi, S., Mitchell, J., Aries, E., and P. Filsfils, C., Previdi, S., Mitchell, J., Aries, E., and P.
Lapukhov, "BGP-Prefix Segment in large-scale data Lapukhov, "BGP-Prefix Segment in large-scale data
centers", draft-ietf-spring-segment-routing-msdc-02 (work centers", draft-ietf-spring-segment-routing-msdc-04 (work
in progress), October 2016. in progress), March 2017.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760, "Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007, DOI 10.17487/RFC4760, January 2007,
<http://www.rfc-editor.org/info/rfc4760>. <http://www.rfc-editor.org/info/rfc4760>.
[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 15, line 27 skipping to change at page 16, line 4
Italy Italy
Email: sprevidi@cisco.com Email: sprevidi@cisco.com
Clarence Filsfils Clarence Filsfils
Cisco Systems Cisco Systems
Brussels Brussels
Belgium Belgium
Email: cfilsfils@cisco.com Email: cfilsfils@cisco.com
Acee Lindem Acee Lindem
Cisco Systems Cisco Systems
170 W. Tasman Drive 170 W. Tasman Drive
San Jose, CA 95124 95134 San Jose, CA 95124 95134
USA USA
Email: acee@cisco.com Email: acee@cisco.com
Keyur Patel
Cisco Systems
170 W. Tasman Drive
San Jose, CA 95124 95134
USA
Email: keyupate@cisco.com
Arjun Sreekantiah Arjun Sreekantiah
Cisco Systems Cisco Systems
170 W. Tasman Drive 170 W. Tasman Drive
San Jose, CA 95124 95134 San Jose, CA 95124 95134
USA USA
Email: asreekan@cisco.com Email: asreekan@cisco.com
Saikat Ray
Unaffiliated
Email: raysaikat@gmail.com
Hannes Gredler Hannes Gredler
RtBrick Inc. RtBrick Inc.
Email: hannes@rtbrick.com Email: hannes@rtbrick.com
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