< draft-xiong-pce-stateful-pce-sr-inter-domain-00.txt   draft-xiong-pce-stateful-pce-sr-inter-domain-01.txt >
PCE WG Quan Xiong PCE WG Quan Xiong
Internet-Draft Fangwei Hu Internet-Draft Fangwei Hu
Intended status: Standards Track Greg Mirsky Intended status: Standards Track Greg Mirsky
Expires: June 13, 2019 ZTE Corporation Expires: January 8, 2020 ZTE Corporation
Weiqiang Cheng Weiqiang Cheng
China Mobile China Mobile
Dec 10, 2018 July 7, 2019
Stateful PCE for SR-MPLS-TP Inter-domain Stateful PCE for SR-MPLS Inter-domain
draft-xiong-pce-stateful-pce-sr-inter-domain-00 draft-xiong-pce-stateful-pce-sr-inter-domain-01
Abstract Abstract
This document proposes two solutions to perform the Segment routing This document proposes two solutions to perform the Segment Routing
transport Profile with MPLS data plane(SR-MPLS-TP) inter-domain path with MPLS data plane (SR-MPLS) inter-domain path computation and
computation and initiation with stateful PCEs including stitching initiation with stateful PCEs and the use of Path Segment.
Association Group and stitching labels.
Status of This Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. The SR-MPLS-TP Inter-domain with PCE . . . . . . . . . . . . 3 2. The SR-MPLS Inter-domain with PCE . . . . . . . . . . . . . . 3
2.1. The Stitching LSP Association Solution . . . . . . . . . 5 2.1. The Stitching LSP Association Solution . . . . . . . . . 5
2.2. The Stitching Label Solution . . . . . . . . . . . . . . 6 2.2. The Stitching Label Solution . . . . . . . . . . . . . . 6
3. Inter-domain Path Segment Allocation . . . . . . . . . . . . 6 3. Inter-domain Path Segment Allocation . . . . . . . . . . . . 6
3.1. PCC Allocated . . . . . . . . . . . . . . . . . . . . . . 6 3.1. PCC Allocated . . . . . . . . . . . . . . . . . . . . . . 6
3.2. PCE Allocated . . . . . . . . . . . . . . . . . . . . . . 7 3.2. PCE Allocated . . . . . . . . . . . . . . . . . . . . . . 7
4. PCEP Procedure . . . . . . . . . . . . . . . . . . . . . . . 7 4. PCEP Procedure . . . . . . . . . . . . . . . . . . . . . . . 7
4.1. HPCE-initiated LSP . . . . . . . . . . . . . . . . . . . 7 4.1. HPCE-initiated LSP . . . . . . . . . . . . . . . . . . . 7
4.2. PCC-initiated LSP . . . . . . . . . . . . . . . . . . . . 8 4.2. PCC-initiated LSP . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.1. Informative References . . . . . . . . . . . . . . . . . 9 8.1. Informative References . . . . . . . . . . . . . . . . . 9
8.2. Normative References . . . . . . . . . . . . . . . . . . 9 8.2. Normative References . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
The Path Computation Element (PCE) architecture is defined in The Path Computation Element (PCE) architecture is defined in
[RFC4655] for MPLS Traffic Engineering (MPLS-TE) and Generalized MPLS [RFC4655] for MPLS Traffic Engineering (MPLS-TE) and Generalized MPLS
(GMPLS) networks. The Path Computation Element Communication (GMPLS) networks. The Path Computation Element Communication
Protocol (PCEP) defined in [RFC5440] provides mechanisms for PCEs to Protocol (PCEP) defined in [RFC5440] provides mechanisms for PCEs to
perform path computations in response to Path Computation Clients perform path computations in response to Path Computation Clients
(PCCs) requests. (PCCs) requests.
[I-D.ietf-pce-segment-routing] proposes extensions to PCEP that allow [I-D.ietf-pce-segment-routing] proposes extensions to PCEP that allow
a stateful PCE to compute TE paths in segment routing (SR) networks. a stateful PCE to compute TE paths in segment routing (SR) networks.
As defined in [I-D.cheng-spring-mpls-path-segment], a path segment is As defined in [I-D.ietf-spring-mpls-path-segment], a path segment is
used to identify a SR path and support bidirectional SR paths used to identify a SR path and support bidirectional SR paths
correlation. [I-D.xiong-pce-pcep-extension-sr-tp] proposed a correlation. [I-D.li-pce-sr-path-segment] proposed the extension for
mechanism to create the bidirectional SR tunnel in a single SR PCEP to operate with Path Segment. [I-D.li-pce-sr-bidir-path]
domain. [I-D.hu-mpls-sr-inter-domain-use-cases] defined a inter- proposed the extension for PCEP to group two unidirectional SR Paths
domain path segment and related inter-domain use cases for Segment into an Associated Bidirectional SR Path.
Routing in MPLS Transport Profile (SR-MPLS-TP) networks. It is [I-D.xiong-spring-path-segment-sr-inter-domain] proposes the use of
Path Segment in inter-domain scenarios for SR-MPLS network. It is
required to perform the SR inter-domain path computation and required to perform the SR inter-domain path computation and
initiation with PCE deployment. initiation with PCE deployment.
The path computation requirments for Label Switched Paths (LSPs) The path computation requirments for Label Switched Paths (LSPs)
across multiple domains are discussed in [RFC4105] and [RFC4216]. across multiple domains are discussed in [RFC4105] and [RFC4216].
Inter-domain path computation can be performed by a single stateful Inter-domain path computation can be performed by a single stateful
PCE and multiple stateful PCEs. The PCE may has no ability to PCE and multiple stateful PCEs. The PCE may has no ability to
collect the topologies all over the domains. So the single PCE model collect the topologies all over the domains. So the single PCE model
is not applied in deployment. Three multiple PCEs models can be uesd is not applied in deployment. Three multiple PCEs models can be uesd
to perform PCE-based inter-domain path computation including Per- to perform PCE-based inter-domain path computation including Per-
Domain Path Computation [RFC5152], Backward-Recursive PCE-Based Domain Path Computation [RFC5152], Backward-Recursive PCE-Based
Computation (BRPC) [RFC5441] and Hierarchical PCE (H-PCE) [RFC6805]. Computation (BRPC) [RFC5441] and Hierarchical PCE (H-PCE) [RFC6805].
Computing the optimum inter-domain path requires co-operation between Computing the optimum inter-domain path requires co-operation between
multiple PCEs. But the sequence of domains need to be known before multiple PCEs. But the sequence of domains need to be known before
the path computation in BRPC mechanism. Stateful H-PCE architecture the path computation in BRPC mechanism. Stateful H-PCE architecture
skipping to change at page 3, line 18 skipping to change at page 3, line 20
is not applied in deployment. Three multiple PCEs models can be uesd is not applied in deployment. Three multiple PCEs models can be uesd
to perform PCE-based inter-domain path computation including Per- to perform PCE-based inter-domain path computation including Per-
Domain Path Computation [RFC5152], Backward-Recursive PCE-Based Domain Path Computation [RFC5152], Backward-Recursive PCE-Based
Computation (BRPC) [RFC5441] and Hierarchical PCE (H-PCE) [RFC6805]. Computation (BRPC) [RFC5441] and Hierarchical PCE (H-PCE) [RFC6805].
Computing the optimum inter-domain path requires co-operation between Computing the optimum inter-domain path requires co-operation between
multiple PCEs. But the sequence of domains need to be known before multiple PCEs. But the sequence of domains need to be known before
the path computation in BRPC mechanism. Stateful H-PCE architecture the path computation in BRPC mechanism. Stateful H-PCE architecture
is appropriate to compute an optimal end-to-end path across multiple is appropriate to compute an optimal end-to-end path across multiple
domains. domains.
As defined in [I-D.hu-mpls-sr-inter-domain-use-cases], two SR-MPLS-TP As defined in [I-D.xiong-spring-path-segment-sr-inter-domain], the
inter-domain models includes stitching and nesting inter-domain SR-MPLS inter-domain models includes stitching and nesting inter-
models. This document proposes two solutions to perform the SR-MPLS- domain models between inter-Area or inter-AS domains. This document
TP inter-domain path computation and initiation with stateful PCEs proposes two solutions to perform the SR-MPLS inter-domain path
including stitching LSPs Association and stitching labels. computation and initiation with stateful PCEs and the use of Path
Segment.
1.1. Requirements Language 1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
1.2. Terminology 1.2. Terminology
The terminology is defined as [RFC5440], The terminology is defined as [RFC5440],
[I-D.ietf-pce-segment-routing] , [I-D.ietf-pce-segment-routing] , [I-D.ietf-spring-mpls-path-segment].
[I-D.cheng-spring-mpls-path-segment].
2. The SR-MPLS-TP Inter-domain with PCE 2. The SR-MPLS Inter-domain with PCE
The SR-MPLS-TP stitching inter-domain scenario is described in The SR-MPLS inter-domain scenario is described in
[I-D.hu-mpls-sr-inter-domain-use-cases]. The SR nodes belong to [I-D.xiong-spring-path-segment-sr-inter-domain]. The domains of the
three Autonomous Systems (AS) including SR-AS1, SR-AS2 and SR-AS3 networks may be IGP Areas or ASes and the inter- domain scenario may
which connecting with logical links or border nodes as the Figure 1 be inter-Area or inter-AS. The multiple SR-MPLS domains may be
shown. The SR inter-domain LSP needs to be provided along the inter- interconnect with a ABR within areas or inter-link between ASes. As
AS paths. The Path 1~5 are forwarding path segments and Path 1'~5' the Figure 1 shown, SR-AS1, SR-AS2 and SR-AS3 interconnect with
are the related reverse path segments and these are all inter-domain logical links and SR-Area1, SR-Area2 and SR-Area3 interconnect within
path segments. border nodes. The SR end-to-end bidirectional LSP needs to be
provided along the multi-domain paths. The Path 1~5 are forwarding
path segments and Path 1'~5' are the related reverse path segments
and these are all inter-domain path segments.
+-------+ +-------+
+------------------+ H-PCE +-------------------+ +------------------+ H-PCE +-------------------+
| +---+---+ | | +---+---+ |
| | | | | |
v v v v v v
+--+--+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+
|PCE-1| |PCE-2| |PCE-3| |PCE-1| |PCE-2| |PCE-3|
+--+--+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+
| | | | | |
v v v v v v
SR Border Node Network: SR Inter-Area:
.................. ................. .................... .................. ................. ....................
. . . . . . . . . . . .
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+
| A | | X | | Y | | Z | | A | | X | | Y | | Z |
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+
. SR-AS1 . . SR-AS2 . . SR-AS3 . . SR-Area1 . . SR-Area2 . . SR-Area3 .
.................. ................. .................... .................. ................. ....................
Forwarding Path Segments: Forwarding Path Segments:
|------Path1------->|-----Path2------->|--------Path3------>| |------Path1------->|-----Path2------->|--------Path3------>|
Reverse Path Segments: Reverse Path Segments:
|<-----Path1'-------|<----Path2'-------|<--------Path3'-----| |<-----Path1'-------|<----Path2'-------|<--------Path3'-----|
SR Border Link Network: SR Inter-AS:
.................... .................... ..................... .................... .................... .....................
. . . . . . . . . . . .
. +---+ +---+ . . +---+ +---+ . . +---+ +----+ . . +---+ +---+ . . +---+ +---+ . . +---+ +----+ .
. | A |------| B |-------| C |-----| X |---------| Y |-----| Z | . . | A |------| B |-------| C |-----| X |---------| Y |-----| Z | .
. +---+ +---+ . . +---+ +---+ . . +---+ +----+ . . +---+ +---+ . . +---+ +---+ . . +---+ +----+ .
. SR-AS1 . . SR-AS2 . . SR-AS3 . . SR-AS1 . . SR-AS2 . . SR-AS3 .
.................... .................... ..................... .................... .................... .....................
Forwarding Path Segments: Forwarding Path Segments:
|----Path1---->|-Path2-->|----Path3--->|-Path4-->|-----Path5------>| |----Path1---->|-Path2-->|----Path3--->|-Path4-->|-----Path5------>|
Reverse Path Segments: Reverse Path Segments:
|<---Path1'----|<-Path2'-|<---Path3'---|<-Path4'-|<----Path5'------| |<---Path1'----|<-Path2'-|<---Path3'---|<-Path4'-|<----Path5'------|
Figure 1 The SR Stitching Inter-Domain with H-PCE Figure 1 The SR Inter-Domain with H-PCE
The hierarchical PCE architecture is described in [RFC6805], a parent The hierarchical PCE architecture is described in [RFC6805], a parent
PCE maintains a domain topology map that contains the child domains PCE maintains a domain topology map that contains the child domains
(seen as vertices in the topology) and their interconnections (links (seen as vertices in the topology) and their interconnections (links
in the topology) but no information about the content of the child in the topology) but no information about the content of the child
domains. Each child domain has one PCE taking in charge of computing domains. Each child domain has one PCE taking in charge of computing
paths across its own domain. These PCEs are known as child PCEs and paths across its own domain. These PCEs are known as child PCEs and
have a relationship with the parent PCE. As the Figure 1 shown, have a relationship with the parent PCE. As the Figure 1 shown,
H-PCE is parent PCE and PCE-1, PCE-2 and PCE-3 are child PCEs which H-PCE is parent PCE and PCE-1, PCE-2 and PCE-3 are child PCEs which
is responsible for each own SR-AS. is responsible for each own SR-AS.
skipping to change at page 5, line 19 skipping to change at page 5, line 19
initiate the path computation. The parent PCE selects a set of initiate the path computation. The parent PCE selects a set of
candidate domain paths based on the domain topology and the state of candidate domain paths based on the domain topology and the state of
the inter-domain links. It then sends computation requests to the the inter-domain links. It then sends computation requests to the
child PCEs responsible for each of the domains on the candidate child PCEs responsible for each of the domains on the candidate
domain paths. The stateful child PCE in each domain performs active domain paths. The stateful child PCE in each domain performs active
stateful procedure as defined [RFC8231]. stateful procedure as defined [RFC8231].
2.1. The Stitching LSP Association Solution 2.1. The Stitching LSP Association Solution
The LSPs of multiple domains can be stitched together by adding them The LSPs of multiple domains can be stitched together by adding them
to a stitching LSP association group as defined in [I-D.hu-pce- to a stitching LSP association group as defined in
stitching-lsp-association]. As the Figure 2 shown, the stateful [I-D.hu-pce-stitching-lsp-association]. As the Figure 2 shown, the
H-PCE sends the PCInit message defined in [RFC8281] to initiate the stateful H-PCE sends the PCInit message defined in [RFC8281] to
inter-domain path computation adding the forwarding LSP 1~3 to initiate the inter-domain path computation adding the forwarding LSP
Assoc#1 and reverse LSP 1'~3' to Assoc#2. The child PCEs may 1~3 to Assoc#1 and reverse LSP 1'~3' to Assoc#2. The child PCEs may
initiate the intra-domain LSPs when receiving the message from parent initiate the intra-domain LSPs when receiving the message from parent
PCE. PCE.
+-------+ +-------+
+------------------+ H-PCE +-----------------+ +------------------+ H-PCE +-----------------+
PCInit | +---+---+ | PCInit | +---+---+ |
(LSP1,Assoc#1) | PCInit(LSP2,Assoc#1)| PCInit(LSP3,Assoc#1)| (LSP1,Assoc#1) | PCInit(LSP2,Assoc#1)| PCInit(LSP3,Assoc#1)|
PCInit | PCInit(LSP2',Assoc#2 |PCInit(LSP3',Assoc#2 | PCInit | PCInit(LSP2',Assoc#2 |PCInit(LSP3',Assoc#2 |
(LSP1',Assoc#2)| | | (LSP1',Assoc#2)| | |
v v v v v v
skipping to change at page 6, line 7 skipping to change at page 6, line 7
v v v v v v v v v v v v
+-----+ LSP1 +-----------+ LSP2 +-----------+ LSP3 +-----+ +-----+ LSP1 +-----------+ LSP2 +-----------+ LSP3 +-----+
| A |-------->| X |--------->| Y |-------->| Z | | A |-------->| X |--------->| Y |-------->| Z |
| |<--------| |<---------| |<--------| | | |<--------| |<---------| |<--------| |
+-----+ LSP1' +-----------| LSP2' +-----------+ LSP3' +-----+ +-----+ LSP1' +-----------| LSP2' +-----------+ LSP3' +-----+
Figure 2 The SR inter-domain Stitching LSP Association Figure 2 The SR inter-domain Stitching LSP Association
2.2. The Stitching Label Solution 2.2. The Stitching Label Solution
This section defined the inter-domain path segments as stitching The Path Segment can be used for path stithing. The SR sub-paths can
Labels which used to stitch per-domain LSP tunnels in order to form be correlated with the use of Path Segment. This section defined the
inter-domain path that cross multiple domains. path segments as stitching Labels which used to stitch per-domain LSP
tunnels in order to create end-to-end path that cross multiple
domains.
SR intra-domain path is setup as part of inter-domain SR path. When SR intra-domain path is setup as part of inter-domain SR path. When
PCC requests the PCE or the PCE itself to initiate The SR path, the PCC requests the PCE or the PCE itself to initiate The SR path, the
inter-domain path segments should be carried as a stitching Label inter-domain path segments should be carried as a stitching Label
with the associated link. with the associated link.
+-------+ +-------+
+------------------+ H-PCE +-----------------+ +------------------+ H-PCE +-----------------+
PCInit | +---+---+ | PCInit | +---+---+ |
(LSP1,LSP1')| PCInit(LSP2,LSP2')| PCInit(LSP3,LSP3')| (LSP1,LSP1')| PCInit(LSP2,LSP2')| PCInit(LSP3,LSP3')|
skipping to change at page 6, line 40 skipping to change at page 6, line 42
SL:Stiching Label SL:Stiching Label
Figure 3 The SR Inter-Domain Stitching Label Figure 3 The SR Inter-Domain Stitching Label
3. Inter-domain Path Segment Allocation 3. Inter-domain Path Segment Allocation
The inter-domain path segment may be allocated by PCC or PCE. The The inter-domain path segment may be allocated by PCC or PCE. The
PCE may be the single domain PCE which taking in charge of the PCE may be the single domain PCE which taking in charge of the
respective domain. The inter-domain path segments is a unique value respective domain. The inter-domain path segments is a unique value
in the domain which PCC or PCE belongs to. The mechanism of path in the domain which PCC or PCE belongs to. The operation of path
segment request and reply may be the same with that in single domain segment request and reply may be the same with that in single domain
as defined in [I-D.xiong-pce-pcep-extension-sr-tp]. as defined in [I-D.li-pce-sr-path-segment].
3.1. PCC Allocated 3.1. PCC Allocated
As defined in [I-D.hu-mpls-sr-inter-domain-use-cases], an inter- As defined in [I-D.xiong-spring-path-segment-sr-inter-domain], an
domain path segment can be allocated by egress PCC and may be inter-domain path segment can be allocated by egress PCC and may be
maintained on the PCC itself. The inter-domain path segment connects maintained on the PCC itself. The inter-domain path segment connects
two domains and the ingress and egress PCC are belong to different two domains and the ingress and egress PCC are belong to different
domains. The ingress and egress PCC need to exchange messages which domains. The ingress and egress PCC need to exchange messages which
carrying path segment information between the two PCEs. carrying path segment information between the two PCEs.
The Ingress PCC may request to allocate a path segment from egress The Ingress PCC may request to allocate a path segment from egress
PCC. Once egress PCC allocated the inter-domain path segment, it PCC. Once egress PCC allocated the inter-domain path segment, it
need to inform the PCE in respective domain with the PCRpt message. need to inform the PCE in respective domain with the PCRpt message.
The PCE need to communicate with the PCE which the ingress PCC The PCE need to communicate with the PCE which the ingress PCC
belongs to inform the value allocated. belongs to inform the value allocated.
skipping to change at page 8, line 11 skipping to change at page 8, line 15
The stateful H-PCE initiates the end-to-end path computation across The stateful H-PCE initiates the end-to-end path computation across
multiple domains and selects a set of candidate domain paths based on multiple domains and selects a set of candidate domain paths based on
the topology. the topology.
The stateful H-PCE sends PCInitiate message to every PCEs which the The stateful H-PCE sends PCInitiate message to every PCEs which the
end-to-end path traversed, carrying inter-domain path segments end-to-end path traversed, carrying inter-domain path segments
allocated by H-PCE, stitching LSP association group and the SID list allocated by H-PCE, stitching LSP association group and the SID list
in the ERO object. in the ERO object.
The stateful child PCE in each domain perform active stateful The stateful child PCE in each domain perform active stateful
procedure as defined in [I-D.xiong-pce-pcep-extension-sr-tp]. procedure as defined in [I-D.li-pce-sr-path-segment].
4.2. PCC-initiated LSP 4.2. PCC-initiated LSP
In case of passive path computation request to the ingress PCE from In case of passive path computation request to the ingress PCE from
the ingress LSR, the H-PCE path computation procedure is applied to the ingress LSR, the H-PCE path computation procedure is applied to
compute sequence of domains or end-to-end path by using PCReq and compute sequence of domains or end-to-end path by using PCReq and
PCRep messages among stateful PCEs in passive mode. PCRep messages among stateful PCEs in passive mode.
In case of delegation to the ingress PCE (active stateful PCE), the In case of delegation to the ingress PCE (active stateful PCE), the
ingress child PCE may further delegate to parent PCE as per ingress child PCE may further delegate to parent PCE as per
skipping to change at page 9, line 21 skipping to change at page 9, line 25
8.1. Informative References 8.1. Informative References
[RFC6805] King, D., Ed. and A. Farrel, Ed., "The Application of the [RFC6805] King, D., Ed. and A. Farrel, Ed., "The Application of the
Path Computation Element Architecture to the Determination Path Computation Element Architecture to the Determination
of a Sequence of Domains in MPLS and GMPLS", RFC 6805, of a Sequence of Domains in MPLS and GMPLS", RFC 6805,
DOI 10.17487/RFC6805, November 2012, DOI 10.17487/RFC6805, November 2012,
<https://www.rfc-editor.org/info/rfc6805>. <https://www.rfc-editor.org/info/rfc6805>.
8.2. Normative References 8.2. Normative References
[I-D.cheng-spring-mpls-path-segment] [I-D.hu-pce-stitching-lsp-association]
Cheng, W., Wang, L., Li, H., Chen, M., Gandhi, R., Zigler, hu, f., Xiong, Q., Mirsky, G., and W. Cheng, "Stitching
R., and S. Zhan, "Path Segment in MPLS Based Segment LSP Association", draft-hu-pce-stitching-lsp-
Routing Network", draft-cheng-spring-mpls-path-segment-03 association-00 (work in progress), December 2018.
(work in progress), October 2018.
[I-D.hu-mpls-sr-inter-domain-use-cases]
hu, f., Xiong, Q., Mirsky, G., and W. Cheng, "Segment
Routing in MPLS-TP Inter-domain Use Cases", draft-hu-mpls-
sr-inter-domain-use-cases-00 (work in progress), December
2018.
[I-D.ietf-pce-association-bidir]
Barth, C., Gandhi, R., and B. Wen, "PCEP Extensions for
Associated Bidirectional Label Switched Paths (LSPs)",
draft-ietf-pce-association-bidir-02 (work in progress),
November 2018.
[I-D.ietf-pce-segment-routing] [I-D.ietf-pce-segment-routing]
Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W., Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
and J. Hardwick, "PCEP Extensions for Segment Routing", and J. Hardwick, "PCEP Extensions for Segment Routing",
draft-ietf-pce-segment-routing-14 (work in progress), draft-ietf-pce-segment-routing-16 (work in progress),
October 2018. March 2019.
[I-D.ietf-pce-stateful-hpce] [I-D.ietf-pce-stateful-hpce]
Dhody, D., Lee, Y., Ceccarelli, D., Shin, J., King, D., Dhody, D., Lee, Y., Ceccarelli, D., Shin, J., and D. King,
and O. Dios, "Hierarchical Stateful Path Computation "Hierarchical Stateful Path Computation Element (PCE).",
Element (PCE).", draft-ietf-pce-stateful-hpce-06 (work in draft-ietf-pce-stateful-hpce-11 (work in progress), July
progress), October 2018. 2019.
[I-D.xiong-pce-pcep-extension-sr-tp] [I-D.ietf-spring-mpls-path-segment]
Xiong, Q., hu, f., and S. Zhan, "PCEP extensions for SR Cheng, W., Li, H., Chen, M., Gandhi, R., and R. Zigler,
MPLS-TP", draft-xiong-pce-pcep-extension-sr-tp-02 (work in "Path Segment in MPLS Based Segment Routing Network",
progress), October 2018. draft-ietf-spring-mpls-path-segment-00 (work in progress),
March 2019.
[I-D.li-pce-sr-bidir-path]
Li, C., Chen, M., Cheng, W., Li, Z., Dong, J., Gandhi, R.,
and Q. Xiong, "PCEP Extensions for Associated
Bidirectional Segment Routing (SR) Paths", draft-li-pce-
sr-bidir-path-05 (work in progress), March 2019.
[I-D.li-pce-sr-path-segment]
Li, C., Chen, M., Cheng, W., Dong, J., Li, Z., Gandhi, R.,
and Q. Xiong, "Path Computation Element Communication
Protocol (PCEP) Extension for Path Segment in Segment
Routing (SR)", draft-li-pce-sr-path-segment-05 (work in
progress), March 2019.
[I-D.xiong-spring-path-segment-sr-inter-domain]
Xiong, Q., Mirsky, G., and W. Cheng, "The Use of Path
Segment in SR Inter-domain Scenarios", draft-xiong-spring-
path-segment-sr-inter-domain-00 (work in progress), July
2019.
[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>.
[RFC4105] Le Roux, J., Ed., Vasseur, J., Ed., and J. Boyle, Ed., [RFC4105] Le Roux, J., Ed., Vasseur, J., Ed., and J. Boyle, Ed.,
"Requirements for Inter-Area MPLS Traffic Engineering", "Requirements for Inter-Area MPLS Traffic Engineering",
RFC 4105, DOI 10.17487/RFC4105, June 2005, RFC 4105, DOI 10.17487/RFC4105, June 2005,
<https://www.rfc-editor.org/info/rfc4105>. <https://www.rfc-editor.org/info/rfc4105>.
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