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Versions: (draft-quinn-sfc-nsh-tlv) 00 01 02 03

SFC                                                          Y. Wei, Ed.
Internet-Draft                                           ZTE Corporation
Intended status: Standards Track                                U. Elzur
Expires: November 21, 2020                                         Intel
                                                                S. Majee
                                                       Caber systems inc
                                                            May 20, 2020


 Network Service Header Metadata Type 2 Variable-Length Context Headers
                       draft-ietf-sfc-nsh-tlv-03

Abstract

   This draft describes Network Service Header (NSH) Metadata (MD) Type
   2 variable-length context headers that can be used within a service
   function path.

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 November 21, 2020.

Copyright Notice

   Copyright (c) 2020 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
   (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




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   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.  NSH MD Type 2 format  . . . . . . . . . . . . . . . . . . . .   3
   4.  NSH MD Type 2 Context Headers . . . . . . . . . . . . . . . .   4
     4.1.  Forwarding Context  . . . . . . . . . . . . . . . . . . .   4
     4.2.  Tenant Identifier . . . . . . . . . . . . . . . . . . . .   5
     4.3.  Content Type  . . . . . . . . . . . . . . . . . . . . . .   5
     4.4.  Ingress Network Node Information  . . . . . . . . . . . .   6
     4.5.  Ingress Network Source Interface  . . . . . . . . . . . .   6
     4.6.  Flow ID . . . . . . . . . . . . . . . . . . . . . . . . .   6
     4.7.  Source and/or Destination Groups  . . . . . . . . . . . .   7
     4.8.  Universal Resource Identifier . . . . . . . . . . . . . .   7
     4.9.  Policy Identifier (POLICY_ID) . . . . . . . . . . . . . .   8
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   6.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   8
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
     7.1.  Forwarding Context Types  . . . . . . . . . . . . . . . .   9
     7.2.  Tenant Identifier Types . . . . . . . . . . . . . . . . .   9
     7.3.  Group Types . . . . . . . . . . . . . . . . . . . . . . .  10
     7.4.  URI Types . . . . . . . . . . . . . . . . . . . . . . . .  10
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  11
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   Network Service Header (NSH) [RFC8300] is the Service Function
   Chaining (SFC) encapsulation required to support the SFC
   architecture.  As such, NSH provides following key elements:

   1.  Service Function Path identification.

   2.  Indication of location within a Service Function Path.

   3.  Optional, per-packet metadata (fixed-length or variable).

   [RFC8300] further defines two metadata formats (MD Types): 1 and 2.
   MD Type 1 defines fixed length, 16 bytes-long metadata, whereas MD
   Type 2 defines a variable-length context format for metadata.  This




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   draft defines some common metadata contexts for use with NSH MD Type
   2.

   This draft does not address metadata usage, updating/chaining of
   metadata or other SFP functions.  Those topics are described in
   [RFC8300].

2.  Conventions used in this document

2.1.  Terminology

   This document uses the terminology defined in the SFC Architecture
   [RFC7665]and the Network Service Header [RFC8300]

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.  NSH MD Type 2 format

   A NSH is composed of a 4-byte Base Header, a 4-byte Service Path
   Header and Context Headers.  The Base Header identifies the MD-Type
   in use:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Ver|O|U|    TTL    |   Length  |U|U|U|U|MD Type| Next Protocol |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                         Figure 1: NSH Base Header

   Please refer to NSH [RFC8300] for a detailed header description.

   When the base header specifies MD Type = 0x2, zero or more Variable
   Length Context Headers MAY be added, immediately following the
   Service Path Header.  Therefore, Length = 0x2 indicates that only the
   Base Header followed by the Service Path Header is present.  The
   number, indicated in the Length field, of optional Variable Length
   Context Headers MUST be of an integer indicating length in 4-bytes
   words Figure 2 below depicts the format of the Context Header as
   defined in Section 2.5.1 of [RFC8300].





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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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          Metadata Class       |      Type     |U|    Length   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Variable-Length Metadata                    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 2: NSH Variable-Length Context Headers

4.  NSH MD Type 2 Context Headers

   In [RFC8300] defined that Metadata Class 0x0000 as IETF Base NSH MD
   Class.  In this draft, metadata types are defined for the IETF Base
   NSH MD Class.

4.1.  Forwarding Context

   This metadata context carries a network forwarding context, used for
   segregation and forwarding scope.  Forwarding context can take
   several forms depending on the network environment.  For example,
   VXLAN/VXLAN-GPE VNID, VRF identification or VLAN.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA1  |U|  Length = 8 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   CT  |             Reserved                                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Tenant ID                                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                       Figure 3: Forwarding Context

   where:

      Context Type (CT) is four bits-long field that defines the length
      and the interpretation of the Tenant ID field.  Please see the
      IANA Considerations in Section 7.  This document defines these CT
      values:

         0x0 - 24 bits VXLAN/LISP virtual network identifier (VNI)

         0x1 - 20 bits MPLS VPN label

         0x2 - 12 bits VLAN identifier




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4.2.  Tenant Identifier

   Tenant identification is often used for segregation within a multi-
   tenant environment.  Orchestration system-generated tenant IDs are an
   example of such data.  This context header carries both the format
   and value of the Tenant identifier.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = 0x02  |U|  Length=12  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  TT   |             Reserved                                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                         Tenant ID                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                         Tenant ID                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Figure 4: Tenant Identifier List

   where:

      Tenant Type (TT) is four bits-long field that specifies the length
      of the Tenant ID field.  This document defines the following
      values for TT:

      *  0x0 - 32 bits-long Tenant ID

      *  0x1 - 64 bits-long Tenant ID

4.3.  Content Type

   Provides explicit information about the content being carried, for
   example, type of video or content value for billing purposes.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA3  |U|  Length = 4 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     Content Type                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                          Figure 5: Content Type






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4.4.  Ingress Network Node Information

   This context carries Node ID of the ingress network node.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA4  |U|  Length = 8 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Node ID                                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Figure 6: Ingress Network Node ID

4.5.  Ingress Network Source Interface

   This context carries the ingress interface of the ingress network
   node.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA5  |U|  Length = 8 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     Source Interface/Port                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                Figure 7: Ingress Network Source Interface

4.6.  Flow ID

   Flow ID provides a representation of the flow.  Akin, but not
   identical to the usage described in [RFC6437].

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA6  |U|  Length = 4 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     Flow ID                                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                             Figure 8: Flow ID








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4.7.  Source and/or Destination Groups

   Intent-based systems can use this data to express the logical
   grouping of source and/or destination objects.  [GROUPBASEDPOLICY]
   and [GROUPPOLICY] provide examples of such a system.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA7  |U|  Length=12  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  GT   |                Reserved                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Source Group                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Dest Group                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                         Figure 9: End Point Group

   where:

      Group Type (GT) is four bits-long field that specifies the the
      interpretation of Source Group and/or Destination Group fields.
      This document defines the following values for GT:

      *  0x1 - Group Based Policy (GBP) end point group (EPG)

4.8.  Universal Resource Identifier

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA8  |U|  Length=var |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  UT   |                URI                                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                        URI                                    ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                 Figure 10: Universal Resource Identifier

   where

      URI (Universal Resource Identifier) Type is four bits-long field
      that specifies the format of the URI field.  This document defines
      the following values for the URI Type field:



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      *  0x1: URI in standard string format as defined in [RFC3986].

      *  0x2: URI represented in a compacted hash format.

4.9.  Policy Identifier (POLICY_ID)

   The policy is often referred by a system-generated identifier which
   is then used by the devices to lookup the content of the policy
   locally.  For example, this identifier could be an index to an array,
   a lookup key, a database Id.  The identifier allows enforcement
   agents or services to lookup up the content of their part of the
   policy quite efficiently.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Metadata Class = 0x0000    |  Type = TBA9  |U|  Length=var |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     POLICY_ID                                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                     POLICY_ID                                  ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                           Figure 11: POLICY_ID

5.  Security Considerations

   [RFC8300] describes the requisite security considerations for
   protecting NSH metadata.

6.  Acknowledgments

   The authors would like to thank Paul Quinn, Behcet Sarikaya, Dirk von
   Hugo, Mohamed Boucadair, Carlos Pignataro and Gregory Mirsky for
   providing invaluable concepts and content for this document.

7.  IANA Considerations

   This document requests IANA to assign the following types from the
   "NSH IETF- Assigned Optional Variable-Length Metadata Types" (0x0000
   IETF Base NSH MD Class) registry available at [IANA-NSH-MD2]

   This document defines the following new values (Table 1)in the
   Network Service Header (NSH) metadata context Type registry:







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       +-------+----------------------------------+---------------+
       | Value |           Description            | Reference     |
       +-------+----------------------------------+---------------+
       | TBA1  |        Forwarding Context        | This document |
       | TBA2  |        Tenant Identifier         | This document |
       | TBA3  |           Content Type           | This document |
       | TBA4  |      Ingress Network NodeID      | This document |
       | TBA5  |    Ingress Network Interface     | This document |
       | TBA6  |             Flow ID              | This document |
       | TBA7  | Source and/or Destination Groups | This document |
       | TBA8  |  Universal Resource Identifier   | This document |
       | TBA9  |        Policy Identifier         | This document |
       +-------+----------------------------------+---------------+

                           Table 1: Type Values

7.1.  Forwarding Context Types

   IANA is requested to create and maintain a new sub registry for
   "Forwarding Context" context types at [IANA-NSH-MD2].

   +---------+-------------------------------------------+-------------+
   | Value   |               Context Types               | Reference   |
   +---------+-------------------------------------------+-------------+
   | 0x0     |     24-bits VXLAN/LISP virtual network    | This        |
   |         |              identifier (VNI)             | document    |
   | 0x1     |           20-bits MPLS VPN label          | This        |
   |         |                                           | document    |
   | 0x2     |           12-bit VLAN identifier          | This        |
   |         |                                           | document    |
   | 0x3-0x9 |                 Unassigned                | IETF Review |
   | 0xA-0xE |               Expert Review               | IETF Review |
   | 0xF     |                  Reserved                 | This        |
   |         |                                           | document    |
   +---------+-------------------------------------------+-------------+

                     Table 2: Fowarding Context Types

7.2.  Tenant Identifier Types

   IANA is requested to create and maintain a new sub registry for
   "Tenant Identifier" context types at [IANA-NSH-MD2], with the
   following initial allocation:








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            +-------+-------------------------+---------------+
            | Value | Tenant Identifier Types | Reference     |
            +-------+-------------------------+---------------+
            | 0x0   |  32 bits-long Tenant ID | This document |
            | 0x1   |  64 bits-long Tenant ID | This document |
            +-------+-------------------------+---------------+

                     Table 3: Tenant Identifier Types

7.3.  Group Types

   IANA is requested to create and maintain a new sub registry for
   "Group" context types at [IANA-NSH-MD2], with the following initial
   allocation:

   +---------+------------------------------------------+--------------+
   | Value   |               Group Types                | Reference    |
   +---------+------------------------------------------+--------------+
   | 0x0     |                 Reserved                 | This         |
   |         |                                          | document     |
   | 0x1     | Group Based Policy (GBP) end point group | This         |
   |         |                  (EPG)                   | document     |
   | 0x2-0xE |                Unassigned                | IETF Review  |
   | 0xF     |                 Reserved                 | This         |
   |         |                                          | document     |
   +---------+------------------------------------------+--------------+

                           Table 4: Group Types

7.4.  URI Types

   IANA is requested to create and maintain a new sub registry for
   "Group" context types at [IANA-NSH-MD2], with the following initial
   allocation:

















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   +---------+-------------------------------------------+-------------+
   | Value   |                 URI Types                 | Reference   |
   +---------+-------------------------------------------+-------------+
   | 0x0     |                  Reserved                 | This        |
   |         |                                           | document    |
   | 0x1     |  URI in standard string format as defined | This        |
   |         |                in [RFC3986]               | document    |
   | 0x2     |    URI represented in a compacted hash    | This        |
   |         |                   format                  | document    |
   | 0x3-0xE |                 Unassigned                | IETF Review |
   | 0xF     |                  Reserved                 | This        |
   |         |                                           | document    |
   +---------+-------------------------------------------+-------------+

                            Table 5: URI Types

8.  References

8.1.  Normative References

   [IANA-NSH-MD2]
              IANA, "NSH IETF-Assigned Optional Variable-Length Metadata
              Types", <https://www.iana.org/assignments/nsh/
              nsh.xhtml#optional-variable-length-metadata-types>.

   [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>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.

   [RFC7665]  Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
              Chaining (SFC) Architecture", RFC 7665,
              DOI 10.17487/RFC7665, October 2015,
              <https://www.rfc-editor.org/info/rfc7665>.

   [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>.

   [RFC8300]  Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
              "Network Service Header (NSH)", RFC 8300,
              DOI 10.17487/RFC8300, January 2018,
              <https://www.rfc-editor.org/info/rfc8300>.



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8.2.  Informative References

   [GROUPBASEDPOLICY]
              OpenStack, "Group Based Policy", 2014.

   [GROUPPOLICY]
              OpenDaylight, "Group Policy", 2014.

   [RFC6437]  Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
              "IPv6 Flow Label Specification", RFC 6437,
              DOI 10.17487/RFC6437, November 2011,
              <https://www.rfc-editor.org/info/rfc6437>.

Authors' Addresses

   Yuehua (Corona) Wei (editor)
   ZTE Corporation
   No.50, Software Avenue
   Nanjing  210012
   China

   Email: wei.yuehua@zte.com.cn


   Uri Elzur
   Intel

   Email: uri.elzur@intel.com


   Sumandra Majee
   Caber systems inc

   Email: Sum.majee@gmail.com

















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