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Versions: (draft-cui-mpls-tp-on-demand-cv-id) 00

Network Working Group                                             Z. Cui
Internet-Draft                                                 R. Winter
Intended status: Standards Track                                     NEC
Expires: January 16, 2014                                       L. Zheng
                                                                 M. Chen
                                                Huawei Technologies Ltd.
                                                           July 15, 2013


                ICC Based TLVs for MPLS-TP OAM Functions
                    draft-cui-mpls-tp-oam-tlv-icc-00

Abstract

   This document specifies identifier TLVs for the Multiprotocol Label
   Switching Transport Profile (MPLS-TP).  Several IP-compatible TLVs
   have already been defined.  This document extends the existing set of
   identifier TLVs based on MPLS-TP identifiers following ITU-T
   conventions.

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 http://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 16, 2014.

Copyright Notice

   Copyright (c) 2013 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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   (http://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



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   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
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
     1.2.  Requirements notation . . . . . . . . . . . . . . . . . .   3
   2.  ICC_Operator_ID-based TLVs and sub-TLVs Format  . . . . . . .   3
     2.1.  ICC_Operator_ID-based Source ID TLV . . . . . . . . . . .   3
     2.2.  ICC_Operator_ID-based Destination ID TLV  . . . . . . . .   4
     2.3.  ICC_Operator_ID-based Source MEP ID TLV . . . . . . . . .   4
     2.4.  ICC_Operator_ID TLV . . . . . . . . . . . . . . . . . . .   5
     2.5.  ICC_Operator_ID-based Static LSP sub-TLV  . . . . . . . .   5
     2.6.  ICC_Operator_ID-based Static Pseudowire sub-TLV . . . . .   6
   3.  Extension TLVs for MPLS-TP OAM Functions  . . . . . . . . . .   7
     3.1.  Proactive Connectivity Verification, Continuity Check,
           and Remote Defect Indication  . . . . . . . . . . . . . .   7
     3.2.  On-demand Connectivity Verification and Route Tracing . .   8
     3.3.  MPLS Fault Management . . . . . . . . . . . . . . . . . .   8
     3.4.  Lock Instruct and Loopback  . . . . . . . . . . . . . . .   8
     3.5.  Packet Loss and Delay Measurement . . . . . . . . . . . .   9
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
     5.1.  New ICC-based Source/Destination ID TLVs  . . . . . . . .   9
     5.2.  New ICC-based Source MEP-ID TLV . . . . . . . . . . . . .   9
     5.3.  New ICC_Operator_ID TLV . . . . . . . . . . . . . . . . .  10
   6.  New ICC-based Static LSP and PW TLVs  . . . . . . . . . . . .  10
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .  10
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   Several MPLS-TP OAM functions such as the ones defined in [RFC6426],
   [RFC6427], [RFC6428], [RFC6435] utilize OAM PDUs which carry
   Identifiers (ID) based on IP/MPLS conventions including IP addresses
   and AS numbers.

   However, in ITU-T specified transport networks, the ITU Carrier Code
   (ICC) is traditionally used to identify a carrier/service provider.
   This document defines the corresponding TLVs based on IDs following
   ITU-T conventions [RFC6923].

1.1.  Terminology

   OAM: Operations, Administration, and Maintenance




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   TLV: Type Length Value

   ITU-T: ITU Telecommunication Standardization Sector

   CC: Country Code

   ICC: ITU Carrier Code

   MPLS: Multiprotocol Label Switching

   LSP: Label Switched Path

   PW: Pseudowire

   MEG: Maintenance Entity Group

   UMC: Unique MEG ID Code

   MEP: Maintenance Entity Group End Point

   MIP: Maintenance Entity Group Intermediate Point

1.2.  Requirements notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD","SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  ICC_Operator_ID-based TLVs and sub-TLVs Format

   This document defines ICC_Operator_ID-based TLVs and sub-TLVs to be
   used in place of exiting TLVs based on IP conventions.

2.1.  ICC_Operator_ID-based Source ID TLV

   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 = 12          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                  ICC_Operator_ID    (8 Octets)                +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Node_ID   (4 Octets)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

           Figure 1: ICC_Operator_ID-based Source ID TLV Format



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   The encoding of the ICC_Operator_ID-based Source ID TLV is specified
   in the figure above.

   Type: TBD1 (two octets).

   Length: The length field is two octets and indicates the length of
   the TLV value field.  This TLV has a fixed length and the value is
   always 12.

   ICC Operator ID: The ICC Operator ID field is 8 octets and is encoded
   as specified in [RFC6923].

   Node ID: The node ID field is a 4 octet field and is encoded as
   specified in [RFC6370].

   This TLV does not carry sub-TLVs.

2.2.  ICC_Operator_ID-based Destination ID TLV

   The ICC_Operator_ID-based Destination Identifier TLV has the same
   format as ICC_Operator_ID-based Source Identifier TLV that is
   specified in the figure above (see Figure 1).

   The TLV Type is TBD2.

2.3.  ICC_Operator_ID-based Source MEP ID TLV

   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 = 20          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              ...                              |
   +                                                               +
   |                 ICC_Operator_ID-based MEG                     |
   +                                                               +
   |                              ...                              |
   +                                               +-+-+-+-+-+-+-+-+
   |                              ...              |     Padding   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          MEP_Index            |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Figure 2: ICC_Operator_ID-based Source MEP ID TLV Format

   The encoding of the ICC_Operator_ID-based Source MEP ID TLV is
   specified in the figure above.




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   Type: TBD3 (two octets).

   Length: The length field is two octets in length and indicates the
   length of the TLV value part in octets including the padding.  This
   TLV has a fixed length and the value is always 20.

   ICC_Operator_ID-based MEG: The ICC_Operator_ID-based MEG field is 15
   octets and is encoded as specified in [RFC6923].

   Value: The value field is encoded by appending a 16-bit MEP index as
   defined in [RFC6923].

   Padding: the padding filed is used to align the field with a 4-octet
   boundary.  The length of the padding MUST be included in the length
   field.

   This TLV does not carry sub-TLVs.

2.4.  ICC_Operator_ID TLV

    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 = 8           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                       ICC_Operator_ID                         +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 3: ICC_Operator_ID TLV Format

   The encoding of the ICC_Operator_ID TLV is specified in the figure
   above.

   Type: TBD4 (two octets).

   Length: The length field is two octets in length and indicates the
   length of the TLV value part in octets.  This TLV has a fixed length
   and the value is always 8.

   ICC_Operator_ID: The ICC_Operator_ID field is 8 octets and is encoded
   as specified in [RFC6923].

   This TLV does not carry sub-TLVs.

2.5.  ICC_Operator_ID-based Static LSP sub-TLV




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    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            sub-Type           |          Length = 32          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                    Source ICC_Operator_ID                     +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Source Node ID                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source Tunnel Number      |        LSP Number             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                  Destination ICC_Operator_ID                  +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Destination Node ID                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Destination Tunnel Number   |             Padding           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Figure 4: ICC_Operator_ID-based Static LSP sub-TLV Format

   The encoding of the ICC_Operator_ID-based Static LSP sub-TLV is
   specified in the figure above.

   sub-Type: TBD5 (two octets).

   Length: The length field is two octets in length and indicates the
   length of the TLV value part in octets including the padding.  This
   TLV has a fixed length and the value is always 32.

   The ICC_Operator_ID filds are defined in [RFC6923].  The Node_ID,
   Tunnel Number and LSP Number are defined in [RFC6370].  The Source
   ICC_Operator_ID and Destination ICC_Operator_ID MAY be set to zero in
   case global uniqueness is not required.

   Padding: the padding filed is used to align the field with a 4-octet
   boundary.  The length of the padding MUST be included in the length
   field.

2.6.  ICC_Operator_ID-based Static Pseudowire sub-TLV

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            sub-Type           |          Length = 40          |



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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                      Service Identifier                       +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                    Source ICC_Operator_ID                     +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Source Node ID                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                         Source AC-ID                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                  Destination ICC_Operator_ID                  +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Destination Node ID                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Destination AC-ID                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     Figure 5: ICC_Operator_ID-based Static Pseudowire sub-TLV Format

   The encoding of the ICC_Operator_ID-based Static Pseudowire sub-TLV
   is specified in the figure above.

   sub-Type: TBD6 (two octets).

   Length: The length field is two octets in length and indicates the
   length of the TLV value part in octets.  This TLV has a fixed length
   and the value is always 40.

   The Service Identifier field is defined in [RFC6426].  The
   ICC_Operator_ID fields are defined in [RFC6923].  The Node_ID fields
   are defined in [RFC6370].  The AC-ID fields are defined in [RFC5003].

3.  Extension TLVs for MPLS-TP OAM Functions

   This document specifies the extension for MPLS-TP OAM functions using
   ICC-based TLVs, but does not change the behavior of existing OAM
   functions.

3.1.  Proactive Connectivity Verification, Continuity Check, and Remote
      Defect Indication

   [RFC6428] defines the format of an MPLS-TP CV Message to allow the
   MEPs to proactively monitor the liveliness and connectivity of a



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   transport path (LSP, PW, or a Section) between them.  [RFC6428]
   defines three types of Source MEP-ID TLV for MPLS-TP Connectivity
   Verification such as section MEP-ID, LSP MEP-ID and PW End Point MEP-
   ID.

   When sending MPLS-TP CV Message on ICC based network, the Source MEP-
   ID TLV based on ITU-T conventions (see Section 2.3) MUST be used in
   the MPLS-TP CV Message, with no distinction between sections, LSPs
   and Pseudowires.

3.2.  On-demand Connectivity Verification and Route Tracing

   [RFC6426] specifies an on-demand monitoring mechanism for the MPLS
   Transport Profile (MPLS-TP).  It defines a set of Global_ID-based
   Source/Destination Identifier TLVs to identify the source or
   destination node of an OAM message, and also defined a set of
   Global_ID-based Static LSP sub-TLV and Static Pseudowire sub-TLV to
   identify the LSP and Pseudowire path.

   When sending Non-IP-Based On-Demand CV Packet on ICC based network,
   the Source Identifier TLV (see Section 2.1) and Destination
   Identifier TLV (see Section 2.2) based on ITU-T conventions MUST be
   used in the On-Demand CV Packet instead of Global_ID-based Source
   Identifier TLV and Global_ID-based Destination Identifier TLV.  The
   Static LSP sub-TLVs and Static Pseudowire sub-TLVs also Must be
   replaced by ICC_Operator_ID-based Static LSP sub-TLVs (see
   Section 2.5) and ICC_Operator_ID-based Static Pseudowire sub-TLVs
   (see Section 2.6).

3.3.  MPLS Fault Management

   [RFC6427] specifies a Fault Management messages to indicate service
   disruptive conditions for MPLS-based transport network Label Switched
   Paths, the Fault Management message include a Global_ID TLV.

   When sending Non-IP-Based Fault Management messages on ICC based
   network, the ICC_Operator_ID (see Section 2.4)MUST be used in the
   Fault Management messages instead of the Global_ID TLV based on IP
   conventions.

3.4.  Lock Instruct and Loopback

   [RFC6435] specifies the Lock Instruct message include Source MEP-ID
   TLV to allow the MEPs to lock transport path (LSP, PW, or a Section).







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   When sending Non-IP-Based Fault Management messages on ICC based
   network, the Source MEP-ID TLV based on ITU-T conventions (see
   Section 2.3) MUST be used in the Lock Instruct message instead of
   TLVs based on IP conventions.

3.5.  Packet Loss and Delay Measurement

   [RFC6374] defined the Loss Measurement Message used to measure packet
   loss ratio and packet delay.  This document does not define new TLV
   for it, because no Global_ID TLV is used in this function.

4.  Security Considerations

   TBD

5.  IANA Considerations

5.1.  New ICC-based Source/Destination ID TLVs

   Section 2 defines two new TLV types for use with on-demand CV
   ([RFC6426]).

   IANA is requested to assign the following TLV types from the
   "Multiprotocol Label Switching Architecture (MPLS) Label Switched
   Paths (LSPs) Ping Parameters - TLVs" registry, "TLVs and sub-TLVs"
   sub-registry.

    Type      Length     Value Field
   ------     ------     -----------
    TBD1        12       ICC_Operator_ID-based Source ID TLV
    TBD2        12       ICC_Operator_ID-based Destination ID TLV


5.2.  New ICC-based Source MEP-ID TLV

   Section 2 defines a new TLV types for use with proactive cc-cv-rdi
   ([RFC6426]).

   IANA is requested to assign the following TLV types from the
   "Multiprotocol Label Switching Architecture (MPLS) Label Switched
   Paths (LSPs) Ping Parameters - TLVs" registry, "TLVs and sub-TLVs"
   sub-registry.

    Type      Length     Value Field
   ------     ------     -----------
    TBD3        20        ICC_Operator_ID-based Source MEP-ID TLV





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5.3.  New ICC_Operator_ID TLV

   Section 2 defines a new TLV type for use with MPLS-TP Fault
   Management ([RFC6427]).

   IANA is requested to assign the following TLV types from the
   "Multiprotocol Label Switching Architecture (MPLS) Label Switched
   Paths (LSPs) Ping Parameters - TLVs" registry, "TLVs and sub-TLVs"
   sub-registry.

    Type      Length     Value Field
   ------     ------     -----------
    TBD4        8         ICC_Operator_ID TLV


6.  New ICC-based Static LSP and PW TLVs

   Section 2 defines two new sub-TLV types for use with on-demand
   CV([RFC6426]).

   IANA is requested to assign the following sub-TLV types from the
   "Multiprotocol Label Switching Architecture (MPLS) Label Switched
   Paths (LSPs) Ping Parameters - TLVs" registry, "TLVs and sub-TLVs"
   sub-registry.

   sub-Type      Length      Value Field
   ----------    ------      -----------
     TBD5         32        ICC_Operator_ID-based Static LSP
     TBD6         40        ICC_Operator_ID-based Static PW


7.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5003]  Metz, C., Martini, L., Balus, F., and J. Sugimoto,
              "Attachment Individual Identifier (AII) Types for
              Aggregation", RFC 5003, September 2007.

   [RFC6370]  Bocci, M., Swallow, G., and E. Gray, "MPLS Transport
              Profile (MPLS-TP) Identifiers", RFC 6370, September 2011.

   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay
              Measurement for MPLS Networks", RFC 6374, September 2011.






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   [RFC6426]  Gray, E., Bahadur, N., Boutros, S., and R. Aggarwal, "MPLS
              On-Demand Connectivity Verification and Route Tracing",
              RFC 6426, November 2011.

   [RFC6427]  Swallow, G., Fulignoli, A., Vigoureux, M., Boutros, S.,
              and D. Ward, "MPLS Fault Management Operations,
              Administration, and Maintenance (OAM)", RFC 6427, November
              2011.

   [RFC6428]  Allan, D., Swallow Ed. , G., and J. Drake Ed. , "Proactive
              Connectivity Verification, Continuity Check, and Remote
              Defect Indication for the MPLS Transport Profile", RFC
              6428, November 2011.

   [RFC6435]  Boutros, S., Sivabalan, S., Aggarwal, R., Vigoureux, M.,
              and X. Dai, "MPLS Transport Profile Lock Instruct and
              Loopback Functions", RFC 6435, November 2011.

   [RFC6923]  Winter, R., Gray, E., van Helvoort, H., and M. Betts,
              "MPLS Transport Profile (MPLS-TP) Identifiers Following
              ITU-T Conventions", RFC 6923, May 2013.

Authors' Addresses

   Zhenlong Cui
   NEC

   Email: c-sai@bx.jp.nec.com


   Rolf Winter
   NEC

   Email: Rolf.Winter@neclab.eu


   Lianshu Zheng
   Huawei Technologies Ltd.

   Email: vero.zheng@huawei.com


   Mach(Guoyi) Chen
   Huawei Technologies Ltd.

   Email: mach.chen@huawei.com





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