Internet DRAFT - draft-wang-idr-cpr
draft-wang-idr-cpr
Interdomain Routing Working Group H. Wang
Internet-Draft J. Dong
Intended status: Informational Huawei Technologies
Expires: 22 April 2024 K. Talaulikar
Cisco Systems
T. Han
Huawei Technologies
R. Chen
ZTE Corporation
J. Xie
X. Chen
Huawei Technologies
20 October 2023
BGP Colored Prefix Routing (CPR) for SRv6 based Services
draft-wang-idr-cpr-03
Abstract
This document describes a mechanism to advertise IPv6 prefixes in BGP
which are associated with Color Extended Communities to establish
end-to-end intent-aware paths for SRv6 services. Such IPv6 prefixes
are called "Colored Prefixes", and this mechanism is called Colored
Prefix Routing (CPR). In SRv6 networks, the Colored prefixes are the
SRv6 locators associated with different intent. SRv6 services (e.g.
SRv6 VPN services) with specific intent could be assigned with SRv6
SIDs under the corresponding SRv6 locators, which are advertised as
Colored prefixes. This allows the SRv6 service traffic to be steered
into end-to-end intent-aware paths simply based on the longest prefix
matching of SRv6 Service SIDs to the Colored prefixes. In data
plane, dedicated transport label or SID for the inter-domain path is
not needed, thus the encapsulation efficiency could be optimized.
The existing IPv6 Address Family could be used for the advertisement
of IPv6 Colored prefixes, thus this mechanism is easy to interoperate
and can be deployed incrementally in multi-domain networks.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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This Internet-Draft will expire on 22 April 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. BGP CPR . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Colored Prefix Allocation . . . . . . . . . . . . . . . . 4
2.2. Colored Prefix Advertisement . . . . . . . . . . . . . . 4
2.3. CPR to Intra-domain Path Resolution . . . . . . . . . . . 6
2.4. SRv6 Service Route Advertisement . . . . . . . . . . . . 6
2.5. SRv6 Service Steering . . . . . . . . . . . . . . . . . . 7
3. Encapsulation and Forwarding Processes . . . . . . . . . . . 7
3.1. CPR over SRv6 Intra-Domain Paths . . . . . . . . . . . . 7
3.2. CPR over MPLS Intra-Domain Paths . . . . . . . . . . . . 8
4. Operational Considerations . . . . . . . . . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
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1. Introduction
With the trend of using one common network to carry multiple types of
services, each service type can have different requirements on the
network. Such requirements are usually considered as the "intent" of
the service or customer, and is represented as an abstract notion
called "color".
In network scenarios where the services are delivered across multiple
network domains, there is need to provide the services with different
end-to-end paths to meet the intent.
[I-D.hr-spring-intentaware-routing-using-color] describes the problem
statements and requirements for inter-domain intent-aware routing.
The inter-domain path can be established using either MPLS or IP data
plane. In MPLS based networks, the traditional inter-domain approach
is to establish an end-to-end LSP based on the BGP-LU mechanisms as
defined in [RFC8277]. Each domain or area border node needs to
perform label swapping for the end-to-end BGP-LU LSP, and encapsulate
the label stack which are used for the intra-domain LSP within the
subsequent network domain or area.
While in IP based networks, the IP reachability information can be
advertised to network nodes in different domains using BGP, so that
all the domain or area border nodes have the routes to the IP
prefixes of the destination node in other domains. With the
introduction of SRv6 [RFC8402] [RFC8754] [RFC8986], BGP services are
assigned with SRv6 Service SIDs [RFC9252], which are routable in the
network according to its SRv6 locator prefix. Thus, the inter-domain
path can be established simply based on the inter-domain prefix
routes, and the BGP-LU inter-domain LSP mechanism is not necessary
for IPv6 and SRv6 based networks.
This document describes a mechanism to advertise IPv6 prefixes which
are associated with Color Extended Community to establish end-to-end
intent-aware paths for SRv6 services. The color value in the Color
Extended Community indicate the intent [RFC9256]. Such IPv6 prefixes
are called "Colored Prefixes", and this mechanism is called Colored
Prefix Routing (CPR). In SRv6 networks, the Colored prefixes are the
SRv6 locators associated with different intent. BGP services over
SRv6 (e.g. SRv6 VPN services) [RFC9252] with specific intent could
be assigned with SRv6 SIDs under the corresponding SRv6 locators,
which are advertised as Colored prefixes. This allows the SRv6
service traffic to be steered (as specified in [RFC9252]) into end-
to-end intent-aware paths simply based on the longest prefix matching
of SRv6 Service SIDs to the Colored prefixes. In data plane, the
dedicated transport label or SID for the inter-domain path is not
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needed, thus the encapsulation efficiency could be optimized. The
existing IPv6 Address Family could be used for the advertisement of
IPv6 Colored prefixes, which makes this mechanism easy to
interoperate and can be deployed incrementally in multi-domain
networks.
2. BGP CPR
This section describes the BGP CPR mechanisms. More specifically,
section 2.1 describes the allocation of the IPv6 Colored prefixes,
section 2.2 describes the advertisement of Colored prefixes in BGP,
section 2.3 describes the resolution of CPR routes to the intra-
domain paths, and section 2.4 describes the steering of BGP SRv6
services to CPR routes.
2.1. Colored Prefix Allocation
In SRv6 networks, an SRv6 locator needs to be allocated for each
node. In order to distinguish N different intent, a PE node needs to
be allocated with N SRv6 locators, each of which is associated a
different intent that is identified by a color value. One way to
achieve this is by splitting the base SRv6 locator of the node into N
sub-locators, and these sub-locators are Colored prefixes associated
with different intents.
For example, node PE2 is allocated with the base SRv6 Locator
2001:db8:aaaa:1::/64. In order to provide 16 different intents, this
base SRv6 Locator is split into 16 sub-locators from
2001:db8:aaaa:1:0000::/68 to 2001:db8:aaaa:1:F000::/68, each of these
sub-locators is associated with a different intent, such as low-
delay, high-bandwidth, etc.
2.2. Colored Prefix Advertisement
After the allocation of Colored prefixes on a PE node, routes to
these Colored prefixes need to be advertised both in the local domain
and also to other domains using BGP, so that the BGP SRv6 services
routes could be resolved using the corresponding CPR route.
In a multi-domain IPv6 network, the IPv6 unicast Address Family/
Subsequent Address Family (AFI/SAFI = 2/1) [RFC2545] is used for the
advertisement of the Colored prefix routes. The color extended
community [RFC9012] is carried with the Colored prefix route with the
color value indicating the intent [RFC9256]. The procedure of
Colored prefix advertisement is described using an example with the
following topology:
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Consistent Color Domain:
C1, C2, ...
+--------------+ +--------------+ +-------------+
| | | | | |
| [ASBR11]---[ASBR21] [ASBR23]---[ASBR31] |
--[PE1] [P1] | X | [P2] | X | [P3] [PE3]--
| [ASBR12]---[ASBR22] [ASBR24]---[ASBR32] |
| | | | | |
+--------------+ +--------------+ +-------------+
AS1 AS2 AS3
Colored Prefixes of PE3:
Low delay: 2001:db8:aaaa:1:1000::/68
high bandwidth: 2001:db8:aaaa:1:2000::/68
...
Figure 1. Example Topology for CPR Route Illustration
Assume PE3 is provisioned with two different Colored prefixes CLP-1
and CLP-2 for two different intent such as "low-delay" and "high-
bandwidth" respectively. In this example, It is assumed that the
color representing a specific intent is consistent through all the
domains.
* PE3 originates BGP IPv6 unicast (AFI/SAFI=2/1) route for the
Colored prefixes PE3:CL1:: and PE3:CL2::. Each route should carry
the corresponding color extended community C1 or C2. PE3 also
advertises a route for the base SRv6 Locator prefix PE3:BL, and
there is no color extended community carried with this route.
* ASBR31 and ASBR32 receive the CPR routes of PE3, and advertise the
CPR routes further to ASBR23 and ASBR24 with next-hop set to
itself.
* ASBR23 and ASBR24 receive the CPR routes of PE3. Since the color-
to-intent mapping in AS2 is consistent with that in AS3, the Color
Extended Community in the received CPR routes are kept unchanged.
ASBR23 and ASBR 24 advertise the CPR routes further in AS2 with
the next-hop set to itself.
* The behavior of ASBR21 and ASBR22 are similar to the behavior of
ASBR31 and ASBR32.
* The behavior of ASBR11 and ASBR12 are similar to the behavior of
ASBR31 and ASBR32.
In normal case, the color value in the color extended community
associated with the CPR route is consistent through all the domains.
While in some special cases, one intent may be represented as
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different color value in different domains, then the Color Extended
Community in the CPR routes may be updated at the border nodes of the
domains based on the color-mapping policy.
In network scenarios where some of the intermediate network domains
are MPLS based, the CPR routes may still be advertised using the IPv6
unicast address family (AFI/SAFI=2/1) in the MPLS-based intermediate
domains, and at the MPLS domain border nodes, some route resolution
policy could be used to make the CPR routes resolved to intra-domain
intent-aware MPLS LSPs. Another possible mechanism is to use the
IPv6 LU address family (AFI/SAFI=2/4) to advertise the CPR routes in
the MPLS domains, the detailed procedure is described in
Section 7.1.2.1 of [I-D.agrawal-spring-srv6-mpls-interworking].
2.3. CPR to Intra-domain Path Resolution
A domain border node which receives a CPR route can resolve the CPR
route to an intra-domain color-aware path based on the tuple (N, C),
where N is the next-hop of the CPR route, and C is the color extended
community of the CPR route. The intra-domain color-aware path could
be built with any of the following mechanisms:
* SRv6 or SR-MPLS Policy
* SRv6 or SR-MPLS Flex-Algo
* RSVP-TE
For example, PE1 receives a CPR route to PE3:CL1 with color C1 and
next-hop ASBR11, it can resolve the CPR routes to an intra-domain
SRv6 Policy based on the tuple (ASBR11, C1).
The intra-domain path resolution scheme could be based on any
existing tunnel resolution policy, and new tunnel resolution
mechanisms could be introduced if needed.
2.4. SRv6 Service Route Advertisement
For an SRv6 service which is associated with a specific intent, the
SRv6 Service SID could be allocated under the corresponding Colored
locator prefix. For example, on PE3 in the example topology, an SRv6
VPN service with the low delay intent can be allocated with the SRv6
End.DT4 SID 2001:db8:aaaa:1:1000::0100, where
2001:db8:aaaa:1:1000::/68 is the SRv6 Colored prefix for low delay
service.
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The SRv6 service routes are advertised using the mechanism defined in
[RFC9252]. The inter-domain VPN Option C is used, which means the
next-hop of the SRv6 service route is set to the originating PE and
not changed. Since the intent of the service is embedded in the SRv6
service SID, the SRv6 service route does not need to carry the color
extended community.
2.5. SRv6 Service Steering
With the CPR routing mechanism, the ingress PE node which receives
the SRv6 service routes follows the behavior of SRv6 shortest path
forwarding (refer to Section 5 and 6 of [RFC9252]). The SRv6 service
SID carried in the service route is used as the destination address
in the outer IPv6 header encapsulated to the service packet. If the
corresponding CPR route has been received and installed, longest
prefix matching of SRv6 service SIDs to the Colored prefixes is
performed, then the intra-domain color-aware paths in each network
domain which the CPR route is resolved to are used for forwarding the
SRv6 service traffic.
3. Encapsulation and Forwarding Processes
This section describes the encapsulation and forwarding process of
data packets which are matched with the corresponding CPR route.
3.1. CPR over SRv6 Intra-Domain Paths
Following is an illustration of the packet encapsulation and
forwarding process of CPR over SRv6 Policy. The abstract
representation of IPv6 and SRH in section 6 of [RFC8754] is used.
PE3 is provisioned with a Colored prefix PE3:C1 for "low-delay".
In AS1, the SRv6 Policy for (ASBR11, C1) is represented with SID list
(P1, BR11).
In AS2, the SRv6 Policy for (ASBR23, C1) is represented with the SID
list (P2, BR23).
In AS3, the SRv6 Policy for (PE3, C1) is represented with the SID
list (P3, PE3).
For packets which belong to an SRv6 VPN service associated with the
SRv6 Service SID PE3:CL1.DT, the packet encapsulation and forwarding
process is shown as below:
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PE1 ->P1 : (PE1, P1)(PE3:CL1.DT, BR11; SL=2)(C-pkt)
P1 ->BR11: (PE1, BR11)(PE3:CL1.DT, BR11; SL=1)(C-pkt)
BR11->BR21: (PE1, PE3:CL1.DT)(C-pkt)
BR21->P2 : (PE1, P2)(PE3:CL1.DT, BR23; SL=2)(C-pkt)
P2 ->BR23: (PE1, BR23)(PE3:CL1.DT, BR23; SL=1)(C-pkt)
BR23->BR31: (PE1, PE3:CL1.DT)(C-pkt)
BR31->P3 : (PE1, P3)(PE3:CL1.DT, PE3; SL=2)(C-pkt)
P3 ->PE3 : (PE1, PE3)(PE3:CL1.DT, PE3; SL=1)(C-pkt)
In some network domains, SRv6 Flex-Algo may be used to provide
intent-aware intra-domain path. The encapsulation is similar to the
case with SRv6 Policy.
3.2. CPR over MPLS Intra-Domain Paths
In network scenarios where some of the network domains use MPLS based
data plane, the CPR route can be resolved over a color-aware intra-
domain MPLS LSP. Such intra-domain MPLS LSP may be established using
SR-MPLS Policy, SR-MPLS Flex-Algo or RSVP-TE.
The encapsulation and forwarding of SRv6 service packets (which are
actually IPv6 packets) over an intra-domain MPLS LSP is based on the
MPLS mechanisms as defined in [RFC3031] [RFC3032] and [RFC8660]. The
behavior is similar to that of 6PE [RFC4798].
In AS1, the SR-MPLS Policy for (ASBR11, C1) is represented with
Label-stack (P1, BR11).
In AS2, the SR-MPLS Flex-Algo for (ASBR23, C1) is represented with
Label-stack (BR23).
In AS3, the SR-MPLS Policy for (PE3, C1) is represented with Label-
stack (P3, PE3).
For packets which belong to an SRv6 VPN service associated with the
SRv6 Service SID PE3:CL1.DT, the packet encapsulation and forwarding
process is shown as below:
PE1 ->P1 : Label-stack (P1, BR11) (PE1, PE3:CL1.DT)(C-pkt)
P1 ->BR11: Label-stack (BR11) (PE1, PE3:CL1.DT)(C-pkt)
BR11->BR21: (PE1, PE3:CL1.DT)(C-pkt)
BR21->P2 : Label-stack (BR23) (PE1, PE3:CL1.DT)(C-pkt)
P2 ->BR23: Label-stack (BR23) (PE1, PE3:CL1.DT)(C-pkt)
BR23->BR31: (PE1, PE3:CL1.DT)(C-pkt)
BR31->P3 : Label-stack (P3, PE3) (PE1, PE3:CL1.DT)(C-pkt)
P3 ->PE3 : Label-stack (PE3) (PE1, PE3:CL1.DT)(C-pkt)
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4. Operational Considerations
When the Colored prefixes are assigned as the sub-locators of the
node's base SRv6 locator, the IPv6 unicast route of the base locator
prefix is the covering prefix of all the Colored locator prefixes.
To make sure the Colored locator prefixes can be distributed to the
ingress PE nodes along the border nodes, it is required that route
aggregation be disabled for IPv6 unicast routes which carries the
color extended community.
All the border nodes and the ingress PE nodes needs to install the
Colored locator prefixes into the RIB and FIB. For transit domains
which support the CPR mechanism, the border nodes can use the tuple
(N, C) to resolve the CPR routes to intent-aware intra-domain paths.
For transit domains which do not support the CPR mechanism, the
border nodes would ignore the color extended community and resolve
the CPR routes over a best effort intra-domain path to the next-hop
N, while the CPR route will be advertised further to the downstream
domains with only the next-hop changed to itself. This allows the
CPR routes to be resolved to intent-aware intra-domain paths in any
network domains which support the CPR mechanism, while can fall back
to resolve over best-effort intra-domain path in the legacy network
domains.
In this document, IPv6 Unicast address family is used for the
advertisement of IPv6 Colored prefixes. The primary advantage of
this approach is the improved interoperability with legacy networks
that lack support for intent-aware paths, and the facilitation of
incremental deployment of intent-aware routing mechanisms. One
potential concern arises regarding the necessity of separating
Colored prefixes from public IPv6 unicast routes. While as the IP
prefixes and SRv6 locators of network infrastructure are usually
advertised as part of the IP unicast routes, and appropriate filters
are configured at the boundaries of network administration, this is
not considered to be a significant issue. The proposal in
[I-D.ietf-idr-bgp-car] provides a complementary solution that is also
based on the notion of color indicating the intent and where the SRv6
Locator prefix itself signifies the intent, the difference is that a
separate SAFI is used.
[I-D.ietf-idr-bgp-ct] describes another mechanism for intent-aware
routing, in which the SRv6 service SIDs are not directly associated
with the intent, while additional SRv6 transport SIDs are required
for steering traffic to the inter-domain intent-aware paths, and an
SRv6 operation similar to MPLS label swapping is needed on the border
nodes of network domains.
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5. IANA Considerations
This document makes no request of IANA.
6. Security Considerations
The mechanism described in this document provide an approach for
inter-domain intent-aware routing based on existing BGP protocol
mechanisms. It does not introduce any additional security
considerations than those described in [RFC4271] and [RFC4272].
7. Acknowledgements
The authors would like to thank Shunwan Zhuang, Zhibo Hu, Zhenbin Li
and Dhananjaya Rao for the review and valuable discussion.
8. References
8.1. Normative References
[RFC2545] Marques, P. and F. Dupont, "Use of BGP-4 Multiprotocol
Extensions for IPv6 Inter-Domain Routing", RFC 2545,
DOI 10.17487/RFC2545, March 1999,
<https://www.rfc-editor.org/info/rfc2545>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis",
RFC 4272, DOI 10.17487/RFC4272, January 2006,
<https://www.rfc-editor.org/info/rfc4272>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>.
[RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
<https://www.rfc-editor.org/info/rfc8754>.
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[RFC8986] Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer,
D., Matsushima, S., and Z. Li, "Segment Routing over IPv6
(SRv6) Network Programming", RFC 8986,
DOI 10.17487/RFC8986, February 2021,
<https://www.rfc-editor.org/info/rfc8986>.
[RFC9012] Patel, K., Van de Velde, G., Sangli, S., and J. Scudder,
"The BGP Tunnel Encapsulation Attribute", RFC 9012,
DOI 10.17487/RFC9012, April 2021,
<https://www.rfc-editor.org/info/rfc9012>.
[RFC9252] Dawra, G., Ed., Talaulikar, K., Ed., Raszuk, R., Decraene,
B., Zhuang, S., and J. Rabadan, "BGP Overlay Services
Based on Segment Routing over IPv6 (SRv6)", RFC 9252,
DOI 10.17487/RFC9252, July 2022,
<https://www.rfc-editor.org/info/rfc9252>.
[RFC9256] Filsfils, C., Talaulikar, K., Ed., Voyer, D., Bogdanov,
A., and P. Mattes, "Segment Routing Policy Architecture",
RFC 9256, DOI 10.17487/RFC9256, July 2022,
<https://www.rfc-editor.org/info/rfc9256>.
8.2. Informative References
[I-D.agrawal-spring-srv6-mpls-interworking]
Agrawal, S., Ali, Z., Filsfils, C., Voyer, D., Dawra, G.,
Li, Z., Hegde, S., and S. R. Sangli, "SRv6 and MPLS
interworking", Work in Progress, Internet-Draft, draft-
agrawal-spring-srv6-mpls-interworking-12, 10 July 2023,
<https://datatracker.ietf.org/doc/html/draft-agrawal-
spring-srv6-mpls-interworking-12>.
[I-D.hr-spring-intentaware-routing-using-color]
Hegde, S., Rao, D., Sangli, S. R., Agrawal, S., Filsfils,
C., Talaulikar, K., Patel, K., Uttaro, J., Decraene, B.,
Bogdanov, A., Jalil, L., Xu, X., Gulko, A., Khaddam, M.,
Contreras, L. M., Steinberg, D., Guichard, J., Henderickx,
W., and Co-authors, "Problem statement for Inter-domain
Intent-aware Routing using Color", Work in Progress,
Internet-Draft, draft-hr-spring-intentaware-routing-using-
color-02, 10 July 2023,
<https://datatracker.ietf.org/doc/html/draft-hr-spring-
intentaware-routing-using-color-02>.
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[I-D.ietf-idr-bgp-car]
Rao, D., Agrawal, S., and Co-authors, "BGP Color-Aware
Routing (CAR)", Work in Progress, Internet-Draft, draft-
ietf-idr-bgp-car-02, 6 July 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-idr-bgp-
car-02>.
[I-D.ietf-idr-bgp-ct]
Vairavakkalai, K. and N. Venkataraman, "BGP Classful
Transport Planes", Work in Progress, Internet-Draft,
draft-ietf-idr-bgp-ct-16, 22 September 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-idr-bgp-
ct-16>.
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/info/rfc3031>.
[RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001,
<https://www.rfc-editor.org/info/rfc3032>.
[RFC4798] De Clercq, J., Ooms, D., Prevost, S., and F. Le Faucheur,
"Connecting IPv6 Islands over IPv4 MPLS Using IPv6
Provider Edge Routers (6PE)", RFC 4798,
DOI 10.17487/RFC4798, February 2007,
<https://www.rfc-editor.org/info/rfc4798>.
[RFC8277] Rosen, E., "Using BGP to Bind MPLS Labels to Address
Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
<https://www.rfc-editor.org/info/rfc8277>.
[RFC8660] Bashandy, A., Ed., Filsfils, C., Ed., Previdi, S.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing with the MPLS Data Plane", RFC 8660,
DOI 10.17487/RFC8660, December 2019,
<https://www.rfc-editor.org/info/rfc8660>.
Authors' Addresses
Haibo Wang
Huawei Technologies
China
Email: rainsword.wang@huawei.com
Wang, et al. Expires 22 April 2024 [Page 12]
Internet-Draft BGP CPR for SRv6 Service October 2023
Jie Dong
Huawei Technologies
China
Email: jie.dong@huawei.com
Ketan Talaulikar
Cisco Systems
India
Email: ketant.ietf@gmail.com
Tao Han
Huawei Technologies
China
Email: hantao@huawei.com
Ran Chen
ZTE Corporation
China
Email: chen.ran@zte.com.cn
Jingrong Xie
Huawei Technologies
China
Email: xiejingrong@huawei.com
Xinjun Chen
Huawei Technologies
China
Email: ifocus.chen@huawei.com
Wang, et al. Expires 22 April 2024 [Page 13]