Internet DRAFT - draft-dhody-pce-recv-srlg
draft-dhody-pce-recv-srlg
PCE Working Group D. Dhody
Internet-Draft F. Zhang
Intended status: Standards Track X. Zhang
Expires: March 8, 2019 M. Negi
Huawei Technologies
V. Lopez
O. Gonzalez de Dios
Telefonica I+D
March 8, 2019
PCEP Extensions for Receiving SRLG Information
draft-dhody-pce-recv-srlg-08
Abstract
The Path Computation Element (PCE) provides functions of path
computation in support of traffic engineering (TE) in networks
controlled by Multi-Protocol Label Switching (MPLS) and Generalized
MPLS (GMPLS).
This document provides extensions for the Path Computation Element
Protocol (PCEP) to receive Shared Risk Link Group (SRLG) information
during path computation via encoding this information in the path
computation reply message.
The document is currently dead as there is little interest in this as
of now.
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
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Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 8, 2019.
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Copyright Notice
Copyright (c) 2019 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
Provisions Relating to IETF Documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Usage of SRLG . . . . . . . . . . . . . . . . . . . . . . . . 4
4. PCEP Requirements . . . . . . . . . . . . . . . . . . . . . . 4
5. Extension to PCEP . . . . . . . . . . . . . . . . . . . . . . 5
5.1. SRLG Information TLV . . . . . . . . . . . . . . . . . . 5
5.2. SRLG Subobject in ERO . . . . . . . . . . . . . . . . . . 6
6. Other Considerations . . . . . . . . . . . . . . . . . . . . 6
6.1. Other Path Setup Types . . . . . . . . . . . . . . . . . 6
6.2. Backward Compatibility . . . . . . . . . . . . . . . . . 7
6.3. Confidentiality via PathKey . . . . . . . . . . . . . . . 7
6.4. Coherent SRLG IDs . . . . . . . . . . . . . . . . . . . . 7
7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
8. Manageability Considerations . . . . . . . . . . . . . . . . 8
8.1. Control of Function and Policy . . . . . . . . . . . . . 8
8.2. Information and Data Models . . . . . . . . . . . . . . . 8
8.3. Liveness Detection and Monitoring . . . . . . . . . . . . 8
8.4. Verify Correct Operations . . . . . . . . . . . . . . . . 8
8.5. Requirements On Other Protocols . . . . . . . . . . . . . 8
8.6. Impact On Network Operations . . . . . . . . . . . . . . 9
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
9.1. New TLV . . . . . . . . . . . . . . . . . . . . . . . . . 9
9.2. New Subobjects for the ERO Object . . . . . . . . . . . . 9
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
11.1. Normative References . . . . . . . . . . . . . . . . . . 10
11.2. Informative References . . . . . . . . . . . . . . . . . 11
Appendix A. Contributor Addresses . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
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1. Introduction
As per [RFC4655], PCE based path computation model is deployed in
large, multi-domain, multi-region, or multi-layer networks. In such
case PCEs may cooperate with each other to provide end to end optimal
path.
It is important to understand which TE links in the network might be
at risk from the same failures. In this sense, a set of links can
constitute a 'shared risk link group' (SRLG) if they share a resource
whose failure can affect all links in the set [RFC4202]. H-LSP
(Hierarchical LSP) or S-LSP (Stitched LSP) can be used for carrying
one or more other LSPs as described in [RFC4206] and [RFC6107].
H-LSP and S-LSP may be computed by PCE(s) and further form as a TE
link. The SRLG information of such LSPs can be obtained during path
computation itself and encoded in the PCEP Path Computation Reply
(PCRep) message. [I-D.zhang-ccamp-gmpls-uni-app] describes the use
of a PCE for end to end User-Network Interface (UNI) path
computation.
Note that [RFC8001] specifies a extension to Resource ReserVation
Protocol-Traffic Engineering (RSVP-TE) where SRLG information is
collected at the time of signaling. But in case a PCE or cooperating
PCEs are used for path computation it is recommended that SRLG
information is provided by the PCE(s) during the path computation
itself to the ingress (PCC) rather than receiving this information
during signaling.
Further, for other path setup types (PST), (such as segment routing
(SR), PCE as central controller (PCECC)) using a PCEP based approach
for SRLG information is useful.
[RFC7926] describes a scaling problem with SRLGs in multi-layer
environment and introduce a concept of Macro SRLG (MSRLG). Lower
layer SRLG are abstracted at the time of path computation and can be
the basis to generate such a Macro SRLG at the PCE.
The document is currently dead as there is little interest in this as
of now.
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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2. Terminology
The following terminology is used in this document.
CPS: Confidential Path Segment. A segment of a path that contains
nodes and links that the policy requires not to be disclosed
outside the domain.
PCE: Path Computation Element. An entity (component, application,
or network node) that is capable of computing a network path or
route based on a network graph and applying computational
constraints.
SRLG: Shared Risk Link Group.
UNI: User-Network Interface.
3. Usage of SRLG
[RFC4202] states that a set of links can constitute a 'shared risk
link group' (SRLG) if they share a resource whose failure can affect
all links in the set. For example, two fibers in the same conduit
would be in the same SRLG. If an LSR is required to have multiple
diversely routed LSPs to another LSR, the path computation should
attempt to route the paths so that they do not have any links in
common, and such that the path SRLGs are disjoint.
In case a PCE or cooperating PCEs are used for path computation, the
SRLG information is provided by the PCE(s). For example, disjoint
paths for inter-domain or inter-layer LSPs. In order to achieve path
computation for a secondary (backup) path, a PCC may request the PCE
for a route that must be SRLG disjoint from the primary (working)
path. The Exclude Route Object (XRO) [RFC5521] is used to specify
SRLG information to be explicitly excluded.
4. PCEP Requirements
Following key requirements are identified for PCEP to receive SRLG
information during path computation:
SRLG Indication: The PCEP speaker SHOULD be capable of indicating
whether the SRLG information of the path is to be received during
the path computation procedure to PCE.
SRLG: If requested, the SRLG information SHOULD be received during
the path computation and encoded in the PCEP message from PCE.
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Cooperating PCEs [RFC4655] with inter-PCE communication work together
to provide the end to end optimal path as well as the SRLG
information of this path. During inter-domain or inter-layer path
computation, the aggregating PCE (Parent PCE [RFC6805] or Ingress
PCE(1) [RFC5441] or Higher-Layer PCE [RFC5623]) should receive the
SRLG information of path segments from other PCEs and provide the end
to end SRLG information of the optimal path to the Path Computation
Client (PCC).
5. Extension to PCEP
This document defines a new TLV that can be carried in the LSPA (LSP
Attributes) object [RFC5440] so that a PCEP speaker can request SRLG
information along with the path from the PCE. The SRLG subobject
maybe carried inside the Explicit Route Object (ERO) in the PCEP
message from PCE.
5.1. SRLG Information TLV
This document specify a new TLV for the LSPA Object to indicate that
the PCE SHOULD provide the SRLG information along with the path. Its
format is shown in the following figure:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Flags |S|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
SRLG-INFO TLV
The Type for the TLV is TBD. The length is fixed value of 4. The
value portion consist of -
Reserved (16-bit): MUST be set to zero while sending and ignored
on receipt.
Flags (16-bit): Currently one flag is defined -
S (SRLG - 1 bit): when set, in a PCReq message, this indicates
that the SRLG information of the path SHOULD be provided in the
PCRep message. Otherwise, when cleared, this indicates that
the SRLG information SHOULD NOT be included in the PCRep
message. In a PCRep message, when the S bit is set this
indicates that the returned path in ERO also carry the SRLG
information; otherwise (when the S bit is cleared), the
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returned path does not carry SRLG information. Further incase
of PCRpt [RFC8231] message for delegated LSP the flag indicates
that when PCE computes the path, it SHOULD provide the SRLG
information in PCUpd [RFC8231] message. Incase of PCUpd and
PCInitiate [RFC8281] message, the flag indicates that the ERO
also carry the SRLG information.
5.2. SRLG Subobject in ERO
As per [RFC5440], ERO is used to encode the path and is carried
within a PCRep message to provide the computed path when computation
was successful. Further as per [RFC8231] and [RFC8281], the ERO is
also encoded in PCUpd and PCInitiate message for stateful operations.
The SRLG of a path is the union of the SRLGs of the links in the path
[RFC4202]. The SRLG subobject is defined in [RFC8001] for
ROUTE_RECORD object (RRO). The same subobject format (reproduced
below) can be used by the ERO object in the PCEP messages.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |D| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SRLG ID 1 (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ...... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SRLG ID n (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The meaning and description of Type, Length, D-Bit and SRLG ID can be
found in [RFC8001]. Reserved field MUST be set to zero on
transmission and MUST be ignored on receipt.
The SRLG subobject should be encoded inside the ERO object in the
PCEP messages by the PCE when the S-Bit is set in the SRLG-INFO TLV
(inside LSPA object). Incase no SRLG information is present for the
path, an empty SRLG subobject with Length as 4 (and no SRLG-IDs) is
included.
6. Other Considerations
6.1. Other Path Setup Types
Initially PCEP was used for LSPs that are set up using the RSVP-TE
signaling protocol. However, other TE path setup methods are
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possible within the PCE architecture such as SR
[I-D.ietf-pce-segment-routing].
[RFC8001] describes SRLG information collection via RSVP-TE
extension, which can not be used for Segment Routing (SR), making PCE
the best source for the SRLG information for SR.
6.2. Backward Compatibility
If a PCE receives a PCEP message and the PCE does not understand the
new TLV in the LSPA object, then as per [RFC5440], it would ignore
the TLV. In which case, the PCC will receive ERO with no SRLG
subobject and can determine that the PCE does not support the PCEP
extention as defined in this document.
If PCEP speaker receives a PCEP message with SRLG subobject that it
does not support or recognize, it would act according to the existing
processing rules of the ERO as per [RFC5440].
6.3. Confidentiality via PathKey
[RFC5520] defines a mechanism to hide the contents of a segment of a
path, called the Confidential Path Segment (CPS). The CPS may be
replaced by a path-key that can be conveyed in the PCEP and signaled
within in a RSVP-TE ERO.
When path-key confidentiality is used, encoding SRLG information in
PCRep along with the path-key could be useful to compute a SRLG
disjoint backup path at the later instance.
The path segment that needs to be hidden (that is, CPS) MAY be
replaced in the ERO with a PKS. The PCE MAY use the SRLG Sub-objects
in the ERO along with the PKS sub-object.
6.4. Coherent SRLG IDs
In a multi-layer multi-domain scenario, SRLG ids may be configured by
different management entities in each layer/domain. In such
scenarios, maintaining a coherent set of SRLG IDs is a key
requirement in order to be able to use the SRLG information properly.
Thus, SRLG IDs must be unique. Note that current procedure is
targeted towards a scenario where the different layers and domains
belong to the same operator, or to several coordinated administrative
groups. Ensuring the aforementioned coherence of SRLG IDs is beyond
the scope of this document. Further scenarios, where coherence in
the SRLG IDs cannot be guaranteed are out of the scope of the present
document and are left for further study.
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7. Security Considerations
The procedures defined in this document permit the transfer of SRLG
data between layers or domains during the path computation of LSPs,
subject to policy at the PCE. It is recommended that PCE policies
take the implications of releasing SRLG information into
consideration and behave accordingly during path computation. Other
security concerns are discussed in [RFC5440]. An analysis of the
security issues for routing protocols that use TCP (including PCEP)
is provided in [RFC6952], while [RFC8253] discusses a TLS based
approach to provide secure transport for PCEP.
8. Manageability Considerations
8.1. Control of Function and Policy
A PCE involved in inter-domain or inter-layer path computation should
be capable of being configured with a SRLG processing policy to
specify if the SRLG IDs of the domain or specific layer network can
be exposed to the PCEP peer outside the domain or layer network, or
whether they should be summarized, mapped to values that are
comprehensible to PCC outside the domain or layer network, or removed
entirely.
8.2. Information and Data Models
[RFC7420] describes the PCEP MIB and [I-D.ietf-pce-pcep-yang] specify
PCEP YANG, there are no new MIB Objects or YANG changes for this
document.
8.3. Liveness Detection and Monitoring
Mechanisms defined in this document do not imply any new liveness
detection and monitoring requirements in addition to those already
listed in [RFC5440].
8.4. Verify Correct Operations
Mechanisms defined in this document do not imply any new operation
verification requirements in addition to those already listed in
[RFC5440] and [RFC8231].
8.5. Requirements On Other Protocols
Mechanisms defined in this document do not imply any new requirements
on other protocols. Note that, [RFC8001] provide similar
requirements for signaling protocol.
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8.6. Impact On Network Operations
Mechanisms defined in this document do not have any impact on network
operations in addition to those already listed in [RFC5440] and
[RFC8231].
9. IANA Considerations
IANA assigns values to PCEP parameters in registries defined in
[RFC5440]. IANA is requested to make the following additional
assignments.
9.1. New TLV
IANA maintains the "Path Computation Element Protocol (PCEP) Numbers"
registry and the "PCEP TLV Type Indicators" sub-registry. IANA is
requested to allocate a codepoint for -
Type Meaning Reference
TBD SRLG-INFO This document
This document requests that a new sub-registry, named "SRLG-INFO TLV
Flag Field", is created within the "Path Computation Element Protocol
(PCEP) Numbers" registry to manage the Flag field of the this TLV.
New values are to be assigned by Standards Action [RFC8126]. Each
bit should be tracked with the following qualities:
o Bit number (counting from bit 0 as the most significant bit)
o Capability description
o Defining RFC
The following values are defined in this document:
Bit Description Reference
31 SRLG (S-bit) This document
9.2. New Subobjects for the ERO Object
PCEP uses the ERO registry maintained for RSVP at
http://www.iana.org/assignments/rsvp-parameters/rsvp-
parameters.xhtml. Within this registry IANA maintains sub-registry
for ERO subobject at http://www.iana.org/assignments/rsvp-parameters/
rsvp-parameters.xhtml#rsvp-parameters-25
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Upon approval of this document, IANA is requested to make identical
additions to the registry as follows (which is un-assigned right
now):
Subobject Type Reference
34 SRLG sub-object [This I.D.]
Note that, an allocation for SRLG sub-object for RRO in RSVP-TE is
made for [RFC8001].
10. Acknowledgments
Special thanks to the authors of [RFC8001]. This document borrows
some of text from it.
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/info/rfc5440>.
[RFC8001] Zhang, F., Ed., Gonzalez de Dios, O., Ed., Margaria, C.,
Hartley, M., and Z. Ali, "RSVP-TE Extensions for
Collecting Shared Risk Link Group (SRLG) Information",
RFC 8001, DOI 10.17487/RFC8001, January 2017,
<https://www.rfc-editor.org/info/rfc8001>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
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[RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for Stateful PCE", RFC 8231,
DOI 10.17487/RFC8231, September 2017,
<https://www.rfc-editor.org/info/rfc8231>.
[RFC8281] Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for PCE-Initiated LSP Setup in a Stateful PCE
Model", RFC 8281, DOI 10.17487/RFC8281, December 2017,
<https://www.rfc-editor.org/info/rfc8281>.
11.2. Informative References
[RFC4202] Kompella, K., Ed. and Y. Rekhter, Ed., "Routing Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4202, DOI 10.17487/RFC4202, October 2005,
<https://www.rfc-editor.org/info/rfc4202>.
[RFC4206] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP)
Hierarchy with Generalized Multi-Protocol Label Switching
(GMPLS) Traffic Engineering (TE)", RFC 4206,
DOI 10.17487/RFC4206, October 2005,
<https://www.rfc-editor.org/info/rfc4206>.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.
[RFC5441] Vasseur, JP., Ed., Zhang, R., Bitar, N., and JL. Le Roux,
"A Backward-Recursive PCE-Based Computation (BRPC)
Procedure to Compute Shortest Constrained Inter-Domain
Traffic Engineering Label Switched Paths", RFC 5441,
DOI 10.17487/RFC5441, April 2009,
<https://www.rfc-editor.org/info/rfc5441>.
[RFC5520] Bradford, R., Ed., Vasseur, JP., and A. Farrel,
"Preserving Topology Confidentiality in Inter-Domain Path
Computation Using a Path-Key-Based Mechanism", RFC 5520,
DOI 10.17487/RFC5520, April 2009,
<https://www.rfc-editor.org/info/rfc5520>.
[RFC5521] Oki, E., Takeda, T., and A. Farrel, "Extensions to the
Path Computation Element Communication Protocol (PCEP) for
Route Exclusions", RFC 5521, DOI 10.17487/RFC5521, April
2009, <https://www.rfc-editor.org/info/rfc5521>.
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[RFC5623] Oki, E., Takeda, T., Le Roux, JL., and A. Farrel,
"Framework for PCE-Based Inter-Layer MPLS and GMPLS
Traffic Engineering", RFC 5623, DOI 10.17487/RFC5623,
September 2009, <https://www.rfc-editor.org/info/rfc5623>.
[RFC6107] Shiomoto, K., Ed. and A. Farrel, Ed., "Procedures for
Dynamically Signaled Hierarchical Label Switched Paths",
RFC 6107, DOI 10.17487/RFC6107, February 2011,
<https://www.rfc-editor.org/info/rfc6107>.
[RFC6805] King, D., Ed. and A. Farrel, Ed., "The Application of the
Path Computation Element Architecture to the Determination
of a Sequence of Domains in MPLS and GMPLS", RFC 6805,
DOI 10.17487/RFC6805, November 2012,
<https://www.rfc-editor.org/info/rfc6805>.
[RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of
BGP, LDP, PCEP, and MSDP Issues According to the Keying
and Authentication for Routing Protocols (KARP) Design
Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013,
<https://www.rfc-editor.org/info/rfc6952>.
[RFC7420] Koushik, A., Stephan, E., Zhao, Q., King, D., and J.
Hardwick, "Path Computation Element Communication Protocol
(PCEP) Management Information Base (MIB) Module",
RFC 7420, DOI 10.17487/RFC7420, December 2014,
<https://www.rfc-editor.org/info/rfc7420>.
[RFC7926] Farrel, A., Ed., Drake, J., Bitar, N., Swallow, G.,
Ceccarelli, D., and X. Zhang, "Problem Statement and
Architecture for Information Exchange between
Interconnected Traffic-Engineered Networks", BCP 206,
RFC 7926, DOI 10.17487/RFC7926, July 2016,
<https://www.rfc-editor.org/info/rfc7926>.
[RFC8253] Lopez, D., Gonzalez de Dios, O., Wu, Q., and D. Dhody,
"PCEPS: Usage of TLS to Provide a Secure Transport for the
Path Computation Element Communication Protocol (PCEP)",
RFC 8253, DOI 10.17487/RFC8253, October 2017,
<https://www.rfc-editor.org/info/rfc8253>.
[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.
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[I-D.ietf-pce-pcep-yang]
Dhody, D., Hardwick, J., Beeram, V., and J. Tantsura, "A
YANG Data Model for Path Computation Element
Communications Protocol (PCEP)", draft-ietf-pce-pcep-
yang-09 (work in progress), October 2018.
[I-D.zhang-ccamp-gmpls-uni-app]
Zhang, F., Dios, O., Farrel, A., Zhang, X., and D.
Ceccarelli, "Applicability of Generalized Multiprotocol
Label Switching (GMPLS) User-Network Interface (UNI)",
draft-zhang-ccamp-gmpls-uni-app-05 (work in progress),
February 2014.
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Appendix A. Contributor Addresses
Udayasree Palle
EMail: udayasreereddy@gmail.com
Avantika
India
EMail: s.avantika.avantika@gmail.com
Authors' Addresses
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: dhruv.ietf@gmail.com
Fatai Zhang
Huawei Technologies
Bantian, Longgang District
Shenzhen, Guangdong 518129
P.R.China
EMail: zhangfatai@huawei.com
Xian Zhang
Huawei Technologies
Bantian, Longgang District
Shenzhen, Guangdong 518129
P.R.China
EMail: zhang.xian@huawei.com
Mahendra Singh Negi
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: mahend.ietf@gmail.com
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Victor Lopez
Telefonica I+D
Distrito Telefonica
Edificio Sur 3, 3rd floor
Madrid 28050
Spain
EMail: victor.lopezalvarez@telefonica.com
Oscar Gonzalez de Dios
Telefonica I+D
Distrito Telefonica
Edificio Sur 3, 3rd floor
Madrid 28050
Spain
EMail: oscar.gonzalezdedios@telefonica.com
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