[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01

PCE                                                           Quan Xiong
Internet-Draft                                               Greg Mirsky
Intended status: Standards Track                         ZTE Corporation
Expires: January 8, 2020                                      Fangwei Hu
                                                              Individual
                                                          Weiqiang Cheng
                                                            China Mobile
                                                            July 7, 2019


                       Stitching LSP Association
               draft-hu-pce-stitching-lsp-association-01

Abstract

   The Path Computation Element Communication Protocol (PCEP) provides
   mechanisms for Path Computation Elements (PCEs) to perform path
   computations in response to Path Computation Clients (PCCs) requests.
   [I-D.ietf-pce-association-group] proposed an association mechanism
   for a set of LSPs.

   This document defines the stitching LSP association type and
   stitching LSP association TLV for the inter-domain scenairo.

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/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 8, 2020.

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



Quan Xiong, et al.       Expires January 8, 2020                [Page 1]


Internet-Draft          Stitching LSP association              July 2019


   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   3
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   3.  Stitching LSPs in SR-MPLS Inter-domain Scenario . . . . . . .   3
   4.  PCEP Extension for Stitching LSP  . . . . . . . . . . . . . .   3
     4.1.  Stitching LSP Association Type and Group  . . . . . . . .   4
     4.2.  Stitching LSP Association TLV . . . . . . . . . . . . . .   4
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   5
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   5
     7.1.  Association Object Type . . . . . . . . . . . . . . . . .   5
   8.  Normative References  . . . . . . . . . . . . . . . . . . . .   5
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   6

1.  Introduction

   [RFC5440] describes the Path Computation Element Protocol (PCEP)
   which is used between a Path Computation Element (PCE) and a Path
   Computation Client (PCC) (or other PCE) to enable computation of
   Multi-protocol Label Switching (MPLS) for Traffic Engineering Label
   Switched Path (TE LSP).  [I-D.ietf-pce-association-group] proposed an
   association mechanism to create a grouping of LSPs in the context of
   a PCE.

   [I-D.xiong-pce-stateful-pce-sr-inter-domain] introduces the procedure
   and the PCEP extension to form the inter-domain MPLS data entries and
   the multiple LSPs from multiple contiguous domains need to be
   stitched to an end-to-end LSP in SR inter-domain scenario.

   This document proposes a new association object type called
   "stitching Association LSP type" and TLV called "Stitching LSP
   Association TLV" to associate a grouping of LSPs from multiple
   domains for inter-domain scenario.







Quan Xiong, et al.       Expires January 8, 2020                [Page 2]


Internet-Draft          Stitching LSP association              July 2019


2.  Conventions used in this document

2.1.  Terminology

   The terminology is defined as [RFC5440],
   [I-D.ietf-pce-association-group] and
   [I-D.xiong-pce-stateful-pce-sr-inter-domain].

2.2.  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.

3.  Stitching LSPs in SR-MPLS Inter-domain Scenario

   As described in [I-D.xiong-pce-stateful-pce-sr-inter-domain], the
   domains of the networks may be IGP Areas in stitching inter-domain
   scenario.  As Figure 1 shown, the multiple SR-MPLS domains may be
   interconnect with a ABR within areas.  The multiple LSPs in each
   domain can be stitched to an end-to-end LSP.  The LSP-1, LSP-2 and
   LSP-3 can be associated to a group.


                  B                     E                     X
               +     +              .       .              +      +
            +           +         .           .         +            +
         +                 +    .               .    +                  +
      A        SR-MPLS       C        SR-MPLS     G         SR-MPLS       Z
         +     IGP 1       +    .     IGP 2     .    +      IGP 3       +
            +           +         .           .         +            +
               +     +              .      .               +      +
                  D                     F                      Y

      |-------------------->|------------------->|---------------------->|
                  LSP-1                 LSP-2                 LSP-3


         Figure 1: Stitching LSP in SR-MPLS Inter-domain Scenario

4.  PCEP Extension for Stitching LSP








Quan Xiong, et al.       Expires January 8, 2020                [Page 3]


Internet-Draft          Stitching LSP association              July 2019


4.1.  Stitching LSP Association Type and Group

   An association ID will be used to identify the group and a new
   Association Type is defined in this document, based on the generic
   Association object :

   Association Type (TBD) = Stitching LSP Association Group (SLAG).

   SLAG may carry optional TLVs including but not limited to :

   STITCHING-LSP-ASSOCIATION-TLV: Used to identify the role of stitching
   LSPs, described in Section 4.2.

   As [I-D.ietf-pce-association-group] specified, the capability
   advertisement of the association types supported by a PCEP speaker is
   performed by defining a ASSOC-Type-List TLV to be carried within an
   OPEN object.  The association type which defined in this document
   should be added in the list and be advertised between the PCEP
   speakers before the stitching LSP association.

   Stitching LSP Association could be created dynamically or configured
   by the operator when operator-configured association is needed.

4.2.  Stitching LSP Association TLV

   The format of the Stitching LSP Association TLV is shown in Figure 1.


       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                    |S|T|D|
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



                  Figure 2: Stitching LSP Association TLV

   The fields of the Stitching LSP Association TLV are following:

   Type:16bits, it indicates the stitching LSP Association Group

   TLV: TBD2, the value is assigned by IANA).

   Length: the value is 4, it indicates the length of the TLV is 4
   bytes.



Quan Xiong, et al.       Expires January 8, 2020                [Page 4]


Internet-Draft          Stitching LSP association              July 2019


   Reserved: it is reserved for future use.

   Stitching LSP Association Flags-S:1bit, indicates stitching LSP of
   the source domain when it is set.

   Stitching LSP Association Flags-T:1bit, indicates stitching LSP of
   the transit domain when it is set.

   Stitching LSP Association Flags-D:1bit, indicates stitching LSP of
   the destination layer when it is set.

5.  Security Considerations

   TBA

6.  Acknowledgements

   TBA

7.  IANA Considerations

7.1.  Association Object Type

   This document defines a new association type and TLV in Association
   object which originally defined in [I-D.ietf-pce-association-group].
   IANA is requested to make allocations from the registry, as follows:

      +--------+---------------------------------+------------------+
      | Value  |               Name              |    Reference     |
      +--------+---------------------------------+------------------+
      |  TBD   |  Stitching LSP Association Type | [this document]  |
      |  TBD   |  Stitching LSP Association TLV  | [this document]  |
      +--------+---------------------------------+------------------+

                                  Table 1

8.  Normative References

   [I-D.ietf-pce-association-group]
              Minei, I., Crabbe, E., Sivabalan, S., Ananthakrishnan, H.,
              Dhody, D., and Y. Tanaka, "PCEP Extensions for
              Establishing Relationships Between Sets of LSPs", draft-
              ietf-pce-association-group-09 (work in progress), April
              2019.







Quan Xiong, et al.       Expires January 8, 2020                [Page 5]


Internet-Draft          Stitching LSP association              July 2019


   [I-D.xiong-pce-stateful-pce-sr-inter-domain]
              Xiong, Q., hu, f., Mirsky, G., and W. Cheng, "Stateful PCE
              for SR-MPLS-TP Inter-domain", draft-xiong-pce-stateful-
              pce-sr-inter-domain-00 (work in progress), December 2018.

   [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>.

   [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>.

   [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>.

Authors' Addresses

   Quan Xiong
   ZTE Corporation
   No.6 Huashi Park Rd
   Wuhan, Hubei  430223
   China

   Phone: +86 27 83531060
   Email: xiong.quan@zte.com.cn


   Greg Mirsky
   ZTE Corporation
   USA

   Email: gregimirsky@gmail.com









Quan Xiong, et al.       Expires January 8, 2020                [Page 6]


Internet-Draft          Stitching LSP association              July 2019


   Fangwei Hu
   Individual
   China

   Email: hufwei@gmail.com


   Weiqiang Cheng
   China Mobile
   Beijing
   China

   Email: chengweiqiang@chinamobile.com






































Quan Xiong, et al.       Expires January 8, 2020                [Page 7]


Html markup produced by rfcmarkup 1.129c, available from https://tools.ietf.org/tools/rfcmarkup/