draft-ietf-idr-bgp-ls-segment-routing-msd-09.txt   draft-ietf-idr-bgp-ls-segment-routing-msd-10.txt 
IDR Working Group J. Tantsura IDR Working Group J. Tantsura
Internet-Draft Apstra, Inc. Internet-Draft Apstra, Inc.
Intended status: Standards Track U. Chunduri Intended status: Standards Track U. Chunduri
Expires: April 17, 2020 Futurewei Technologies Expires: August 31, 2020 Futurewei Technologies
K. Talaulikar K. Talaulikar
Cisco Systems Cisco Systems
G. Mirsky G. Mirsky
ZTE Corp. ZTE Corp.
N. Triantafillis N. Triantafillis
Apstra, Inc. Amazon Web Services
October 15, 2019 February 28, 2020
Signaling MSD (Maximum SID Depth) using Border Gateway Protocol Link- Signaling MSD (Maximum SID Depth) using Border Gateway Protocol - Link
State State
draft-ietf-idr-bgp-ls-segment-routing-msd-09 draft-ietf-idr-bgp-ls-segment-routing-msd-10
Abstract Abstract
This document defines a way for a Border Gateway Protocol Link-State This document defines a way for a Border Gateway Protocol - Link
(BGP-LS) speaker to advertise multiple types of supported Maximum SID State (BGP-LS) speaker to advertise multiple types of supported
Depths (MSDs) at node and/or link granularity. Maximum SID Depths (MSDs) at node and/or link granularity.
Such advertisements allow entities (e.g., centralized controllers) to Such advertisements allow entities (e.g., centralized controllers) to
determine whether a particular Segment Identifier (SID) stack can be determine whether a particular Segment Identifier (SID) stack can be
supported in a given network. supported in a given network.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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 April 17, 2020. This Internet-Draft will expire on August 31, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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skipping to change at page 2, line 29 skipping to change at page 2, line 29
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions used in this document . . . . . . . . . . . . 3 1.1. Conventions used in this document . . . . . . . . . . . . 3
1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3 1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3
1.1.2. Requirements Language . . . . . . . . . . . . . . . . 4 1.1.2. Requirements Language . . . . . . . . . . . . . . . . 4
2. Advertisement of MSD via BGP-LS . . . . . . . . . . . . . . . 4 2. Advertisement of MSD via BGP-LS . . . . . . . . . . . . . . . 4
3. Node MSD TLV . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Node MSD TLV . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Link MSD TLV . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Link MSD TLV . . . . . . . . . . . . . . . . . . . . . . . . 5
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 5. Procedures for Defining and Using Node and Link MSD
6. Manageability Considerations . . . . . . . . . . . . . . . . 6 Advertisements . . . . . . . . . . . . . . . . . . . . . . . 6
7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 8 7. Manageability Considerations . . . . . . . . . . . . . . . . 7
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 8. Security Considerations . . . . . . . . . . . . . . . . . . . 8
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 8
10.1. Normative References . . . . . . . . . . . . . . . . . . 8 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
10.2. Informative References . . . . . . . . . . . . . . . . . 8 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
11.1. Normative References . . . . . . . . . . . . . . . . . . 8
11.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
When Segment Routing (SR) [RFC8402] paths are computed by a When Segment Routing (SR) [RFC8402] paths are computed by a
centralized controller, it is critical that the controller learns the centralized controller, it is critical that the controller learn the
Maximum SID Depth (MSD) that can be imposed at each node/link on a Maximum SID Depth (MSD) that can be imposed at each node/link on a
given SR path. This ensures that the Segment Identifier (SID) stack given SR path. This ensures that the Segment Identifier (SID) stack
depth of a computed path doesn't exceed the number of SIDs the node depth of a computed path doesn't exceed the number of SIDs the node
is capable of imposing. is capable of imposing.
[I-D.ietf-pce-segment-routing] defines how to signal MSD in the Path [RFC8664] defines how to signal MSD in the Path Computation Element
Computation Element Protocol (PCEP). The OSPF and IS-IS extensions Protocol (PCEP). The OSPF and IS-IS extensions for signaling of MSD
for signaling of MSD are defined in [RFC8476] and [RFC8491] are defined in [RFC8476] and [RFC8491] respectively.
respectively.
However, if PCEP is not supported/configured on the head-end of a SR However, if PCEP is not supported/configured on the head-end of a SR
tunnel or a Binding-SID anchor node, and controller does not tunnel or a Binding-SID anchor node, and controller does not
participate in IGP routing, it has no way of learning the MSD of participate in IGP routing, it has no way of learning the MSD of
nodes and links. BGP-LS [RFC7752] defines a way to advertise nodes and links. BGP-LS [RFC7752] defines a way to expose topology
topology and associated attributes and capabilities of the nodes in and associated attributes and capabilities of the nodes in that
that topology to a centralized controller. This document defines topology to a centralized controller.
extensions to BGP-LS to advertise one or more types of MSDs at node
and/or link granularity.
Other types of MSD are known to be useful. For example, This document defines extensions to BGP-LS to advertise one or more
[I-D.ietf-ospf-mpls-elc] and [I-D.ietf-isis-mpls-elc] define Readable types of MSDs at node and/or link granularity. Other types of MSD
Label Depth Capability (RLDC) that is used by a head-end to insert an are known to be useful. For example, [I-D.ietf-ospf-mpls-elc] and
Entropy Label (EL) at a depth that can be read by transit nodes. [I-D.ietf-isis-mpls-elc] define Readable Label Depth Capability
(RLDC) that is used by a head-end to insert an Entropy Label (EL) at
a depth that can be read by transit nodes.
In the future, it is expected that new MSD-Types will be defined to In the future, it is expected that new MSD-Types will be defined to
signal additional capabilities, e.g., ELs, SIDs that can be imposed signal additional capabilities, e.g., ELs, SIDs that can be imposed
through recirculation, or SIDs associated with another data plane through recirculation, or SIDs associated with another data plane
such as IPv6. MSD advertisements MAY be useful even if SR itself is such as IPv6. MSD advertisements MAY be useful even if SR itself is
not enabled. For example, in a non-SR MPLS network, MSD defines the not enabled. For example, in a non-SR MPLS network, MSD defines the
maximum label depth. maximum label depth.
1.1. Conventions used in this document 1.1. Conventions used in this document
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their links in a network to a BGP-LS consumer of network topology their links in a network to a BGP-LS consumer of network topology
such as a centralized controller. The centralized controller can such as a centralized controller. The centralized controller can
leverage this information in computation of SR paths and their leverage this information in computation of SR paths and their
instantiation on network nodes based on their MSD capabilities. When instantiation on network nodes based on their MSD capabilities. When
a BGP-LS speaker is originating the topology learnt via link-state a BGP-LS speaker is originating the topology learnt via link-state
routing protocols like OSPF or IS-IS, the MSD information for the routing protocols like OSPF or IS-IS, the MSD information for the
nodes and their links is sourced from the underlying extensions as nodes and their links is sourced from the underlying extensions as
defined in [RFC8476] and [RFC8491] respectively. The BGP-LS speaker defined in [RFC8476] and [RFC8491] respectively. The BGP-LS speaker
may also advertise the MSD information for the local node and its may also advertise the MSD information for the local node and its
links when not running any link-state IGP protocol e.g. when running links when not running any link-state IGP protocol e.g. when running
BGP as the only routing protocol. BGP as the only routing protocol. The Protocol-ID field should be
set to BGP since the link and node attributes have BGP based
identifiers. Deployment model for such case would be: a limited
number (meeting resiliecy requirements) of BGP-LS speakers exposing
the topology to the controller, full-mesh/RouterReflectors for iBGP
or regular eBGP connectivity between every node in the topology.
The extensions introduced in this document allow for advertisement of The extensions introduced in this document allow for advertisement of
different MSD-Types. This document does not define these MSD-Types different MSD-Types. This document does not define these MSD-Types
but leverages the definition, guidelines and the code-point registry but leverages the definition, guidelines and the code-point registry
specified in [RFC8491]. This enables sharing of MSD-Types that may specified in [RFC8491]. This enables sharing of MSD-Types that may
be defined in the future by the IGPs in BGP-LS. be defined in the future by the IGPs in BGP-LS.
3. Node MSD TLV 3. Node MSD TLV
Node MSD is encoded in a new Node Attribute TLV [RFC7752] using the Node MSD is encoded in a new Node Attribute TLV [RFC7752] using the
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* MSD-Type : one of the values defined in the IANA registry * MSD-Type : one of the values defined in the IANA registry
titled "IGP MSD-Types" under the "Interior Gateway Protocol titled "IGP MSD-Types" under the "Interior Gateway Protocol
(IGP) Parameters" registry created by [RFC8491]. (IGP) Parameters" registry created by [RFC8491].
* MSD-Value : a number in the range of 0-255. For all MSD-Types, * MSD-Value : a number in the range of 0-255. For all MSD-Types,
0 represents the lack of ability to impose an MSD stack of any 0 represents the lack of ability to impose an MSD stack of any
depth; any other value represents that of the link when used as depth; any other value represents that of the link when used as
an outgoing interface. an outgoing interface.
5. IANA Considerations 5. Procedures for Defining and Using Node and Link MSD Advertisements
When Link MSD is present for a given MSD-type, the value of the Link
MSD MUST take precedence over the Node MSD. When a Link MSD-type is
not signaled but the Node MSD-type is, then the Node MSD-type value
MUST be considered as the MSD value for that link.
In order to increase flooding efficiency, it is RECOMMENDED that
routers with homogenous link MSD values advertise just the Node MSD
value.
The meaning of the absence of both Node and Link MSD advertisements
for a given MSD-type is specific to the MSD-type. Generally it can
only be inferred that the advertising node does not support
advertisement of that MSD-type. However, in some cases the lack of
advertisement might imply that the functionality associated with the
MSD-type is not supported. The correct interpretation MUST be
specified when an MSD-type is defined in [RFC8491].
6. IANA Considerations
This document requests assigning code-points from the registry "BGP- This document requests assigning code-points from the registry "BGP-
LS Node Descriptor, Link Descriptor, Prefix Descriptor, and Attribute LS Node Descriptor, Link Descriptor, Prefix Descriptor, and Attribute
TLVs" based on table below. Early allocation for these code-points TLVs" based on table below. Early allocation for these code-points
have been done by IANA. have been done by IANA.
+------------+-----------------+---------------------------+ +------------+-----------------+---------------------------+
| Code Point | Description | IS-IS TLV/Sub-TLV | | Code Point | Description | IS-IS TLV/Sub-TLV |
+------------+-----------------+---------------------------+ +------------+-----------------+---------------------------+
| 266 | Node MSD | 242/23 | | 266 | Node MSD | 242/23 |
| 267 | Link MSD | (22,23,25,141,222,223)/15 | | 267 | Link MSD | (22,23,25,141,222,223)/15 |
+------------+-----------------+---------------------------+ +------------+-----------------+---------------------------+
6. Manageability Considerations 7. Manageability Considerations
The new protocol extensions introduced in this document augment the The new protocol extensions introduced in this document augment the
existing IGP topology information that is distributed via [RFC7752]. existing IGP topology information that is distributed via [RFC7752].
Procedures and protocol extensions defined in this document do not Procedures and protocol extensions defined in this document do not
affect the BGP protocol operations and management other than as affect the BGP protocol operations and management other than as
discussed in the Manageability Considerations section of [RFC7752]. discussed in the Manageability Considerations section of [RFC7752].
Specifically, the malformed attribute tests for syntactic checks in Specifically, the malformed attribute tests for syntactic checks in
the Fault Management section of [RFC7752] now encompass the new BGP- the Fault Management section of [RFC7752] now encompass the new BGP-
LS Attribute TLVs defined in this document. The semantic or content LS Attribute TLVs defined in this document. The semantic or content
checking for the TLVs specified in this document and their checking for the TLVs specified in this document and their
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The extensions specified in this document, do not specify any new The extensions specified in this document, do not specify any new
configuration or monitoring aspects in BGP or BGP-LS. The configuration or monitoring aspects in BGP or BGP-LS. The
specification of BGP models BGP and BGP-LS models is an ongoing work specification of BGP models BGP and BGP-LS models is an ongoing work
based on the [I-D.ietf-idr-bgp-model]. The management of the MSD based on the [I-D.ietf-idr-bgp-model]. The management of the MSD
features within an ietf segment-routing stack is also an ongoing work features within an ietf segment-routing stack is also an ongoing work
based on the [I-D.ietf-spring-sr-yang]. Management of the segment based on the [I-D.ietf-spring-sr-yang]. Management of the segment
routing in IGPs is ongoing work for ISIS [I-D.ietf-isis-sr-yang] , routing in IGPs is ongoing work for ISIS [I-D.ietf-isis-sr-yang] ,
and OSPF [I-D.ietf-ospf-sr-yang]. and OSPF [I-D.ietf-ospf-sr-yang].
7. Security Considerations 8. Security Considerations
The advertisement of an incorrect MSD value may have negative The advertisement of an incorrect MSD value may have negative
consequences. If the value is smaller than supported, path consequences. If the value is smaller than supported, path
computation may fail to compute a viable path. If the value is computation may fail to compute a viable path. If the value is
larger than supported, an attempt to instantiate a path that can't be larger than supported, an attempt to instantiate a path that can't be
supported by the head-end (the node performing the SID imposition) supported by the head-end (the node performing the SID imposition)
may occur. The presence of this information may also inform an may occur. The presence of this information may also inform an
attacker of how to induce any of the aforementioned conditions. attacker of how to induce any of the aforementioned conditions.
The document does not introduce additional security issues beyond The document does not introduce additional security issues beyond
discussed in [RFC7752], [RFC8476] and [RFC8491]. However, [RFC7752] discussed in [RFC7752], [RFC8476] and [RFC8491]. However, [RFC7752]
is being revised in [I-D.ietf-idr-rfc7752bis] to provide additional is being revised in [I-D.ietf-idr-rfc7752bis] to provide additional
clarification in several portions of the specification after clarification in several portions of the specification after
receiving feedback from implementers. One of the places that is receiving feedback from implementers. One of the places that is
being clarified is the error handling and security. It is expected being clarified is the error handling and security. It is expected
that after [I-D.ietf-idr-rfc7752bis] is released that implementers that after [I-D.ietf-idr-rfc7752bis] is released that implementers
will update all BGP-LS base implementations improving the error will update all BGP-LS base implementations improving the error
handling for protocol work (including this document) that depend on handling for protocol work (including this document) that depend on
this function. this function.
8. Contributors 9. Contributors
Siva Sivabalan Siva Sivabalan
Cisco Systems Inc. Cisco Systems Inc.
Canada Canada
Email: msiva@cisco.com Email: msiva@cisco.com
9. Acknowledgements 10. Acknowledgements
We like to thank Acee Lindem, Stephane Litkowski and Bruno Decraene We like to thank Acee Lindem, Stephane Litkowski and Bruno Decraene
for their reviews and valuable comments. for their reviews and valuable comments.
10. References 11. References
10.1. Normative References 11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752, Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016, DOI 10.17487/RFC7752, March 2016,
skipping to change at page 8, line 47 skipping to change at page 9, line 19
[RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak, [RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476, "Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476,
DOI 10.17487/RFC8476, December 2018, DOI 10.17487/RFC8476, December 2018,
<https://www.rfc-editor.org/info/rfc8476>. <https://www.rfc-editor.org/info/rfc8476>.
[RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg, [RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491, "Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491,
DOI 10.17487/RFC8491, November 2018, DOI 10.17487/RFC8491, November 2018,
<https://www.rfc-editor.org/info/rfc8491>. <https://www.rfc-editor.org/info/rfc8491>.
10.2. Informative References 11.2. Informative References
[I-D.ietf-idr-bgp-model] [I-D.ietf-idr-bgp-model]
Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP
YANG Model for Service Provider Networks", draft-ietf-idr- YANG Model for Service Provider Networks", draft-ietf-idr-
bgp-model-07 (work in progress), October 2019. bgp-model-07 (work in progress), October 2019.
[I-D.ietf-idr-rfc7752bis] [I-D.ietf-idr-rfc7752bis]
Talaulikar, K., "Distribution of Link-State and Traffic Talaulikar, K., "Distribution of Link-State and Traffic
Engineering Information Using BGP", draft-ietf-idr- Engineering Information Using BGP", draft-ietf-idr-
rfc7752bis-01 (work in progress), September 2019. rfc7752bis-02 (work in progress), November 2019.
[I-D.ietf-isis-mpls-elc] [I-D.ietf-isis-mpls-elc]
Xu, X., Kini, S., Psenak, P., Filsfils, C., and S. Xu, X., Kini, S., Psenak, P., Filsfils, C., Litkowski, S.,
Litkowski, "Signaling Entropy Label Capability and Entropy and M. Bocci, "Signaling Entropy Label Capability and
Readable Label Depth Using IS-IS", draft-ietf-isis-mpls- Entropy Readable Label Depth Using IS-IS", draft-ietf-
elc-09 (work in progress), October 2019. isis-mpls-elc-10 (work in progress), October 2019.
[I-D.ietf-isis-sr-yang] [I-D.ietf-isis-sr-yang]
Litkowski, S., Qu, Y., Sarkar, P., Chen, I., and J. Litkowski, S., Qu, Y., Sarkar, P., Chen, I., and J.
Tantsura, "YANG Data Model for IS-IS Segment Routing", Tantsura, "YANG Data Model for IS-IS Segment Routing",
draft-ietf-isis-sr-yang-06 (work in progress), July 2019. draft-ietf-isis-sr-yang-07 (work in progress), January
2020.
[I-D.ietf-ospf-mpls-elc] [I-D.ietf-ospf-mpls-elc]
Xu, X., Kini, S., Psenak, P., Filsfils, C., and S. Xu, X., Kini, S., Psenak, P., Filsfils, C., Litkowski, S.,
Litkowski, "Signaling Entropy Label Capability and Entropy and M. Bocci, "Signaling Entropy Label Capability and
Readable Label-stack Depth Using OSPF", draft-ietf-ospf- Entropy Readable Label-stack Depth Using OSPF", draft-
mpls-elc-10 (work in progress), October 2019. ietf-ospf-mpls-elc-12 (work in progress), October 2019.
[I-D.ietf-ospf-sr-yang] [I-D.ietf-ospf-sr-yang]
Yeung, D., Qu, Y., Zhang, Z., Chen, I., and A. Lindem, Yeung, D., Qu, Y., Zhang, Z., Chen, I., and A. Lindem,
"YANG Data Model for OSPF SR (Segment Routing) Protocol", "YANG Data Model for OSPF SR (Segment Routing) Protocol",
draft-ietf-ospf-sr-yang-10 (work in progress), August draft-ietf-ospf-sr-yang-11 (work in progress), February
2019. 2020.
[I-D.ietf-pce-segment-routing]
Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
and J. Hardwick, "PCEP Extensions for Segment Routing",
draft-ietf-pce-segment-routing-16 (work in progress),
March 2019.
[I-D.ietf-spring-sr-yang] [I-D.ietf-spring-sr-yang]
Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J. Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J.
Tantsura, "YANG Data Model for Segment Routing", draft- Tantsura, "YANG Data Model for Segment Routing", draft-
ietf-spring-sr-yang-13 (work in progress), July 2019. ietf-spring-sr-yang-15 (work in progress), January 2020.
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol [RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031, Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001, DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/info/rfc3031>. <https://www.rfc-editor.org/info/rfc3031>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>. July 2018, <https://www.rfc-editor.org/info/rfc8402>.
[RFC8664] Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
and J. Hardwick, "Path Computation Element Communication
Protocol (PCEP) Extensions for Segment Routing", RFC 8664,
DOI 10.17487/RFC8664, December 2019,
<https://www.rfc-editor.org/info/rfc8664>.
Authors' Addresses Authors' Addresses
Jeff Tantsura Jeff Tantsura
Apstra, Inc. Apstra, Inc.
Email: jefftant.ietf@gmail.com Email: jefftant.ietf@gmail.com
Uma Chunduri Uma Chunduri
Futurewei Technologies Futurewei Technologies
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Uma Chunduri Uma Chunduri
Futurewei Technologies Futurewei Technologies
Email: umac.ietf@gmail.com Email: umac.ietf@gmail.com
Ketan Talaulikar Ketan Talaulikar
Cisco Systems Cisco Systems
Email: ketant@cisco.com Email: ketant@cisco.com
Greg Mirsky Greg Mirsky
ZTE Corp. ZTE Corp.
Email: gregimirsky@gmail.com Email: gregimirsky@gmail.com
Nikos Triantafillis Nikos Triantafillis
Apstra, Inc. Amazon Web Services
Email: nikos@apstra.com Email: nikost@amazon.com
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