Network Working Group                                  A. Bashandy, Ed.
Internet Draft                                              C. Filsfils
Intended status: Standard Track                             L. Ginsberg
Expires: September 2017                                   Cisco Systems
                                                         Bruno Decraene
                                                                 Orange
                                                         March 10, 2017



     IS-IS Extensions to Support Segment Routing over IPv6 Dataplane
                 draft-bashandy-isis-srv6-extensions-00


Abstract

Segment Routing (SR) allows for a flexible definition of end-to-end
paths by encoding paths as sequences of topological sub-paths, called
"segments".  Segment routing architecture can be implemented over an
MPLS data plane as well as an IPv6 data plane. This draft describes
the IS-IS extensions required to support Segment Routing over an IPv6
data plane.

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Table of Contents

   1. Introduction...................................................3
      1.1. Conventions used in this document.........................3
   2. SRv6-Capabilities sub-TLV......................................4
   3. SRv6-function Descriptor.......................................6
   4. SRv6-SID TLV...................................................7
   5. Function Code points...........................................8
   6. Advertising SRv6 SIDs associated with a Neighbor...............8
      6.1. P2P SRv6 X-SID sub-TLV....................................9
      6.2. LAN SRv6 X-SID sub-TLV...................................10
   7. IANA Considerations...........................................11
      7.1. SRv6 SID TLV and sub-TLVs................................11
      7.2. IS-IS SRv6-functions Codepoints Registry.................12
      7.3. SRv6 Capabilities sub-TLV................................12
      7.4. P2P SRv6 X-SID and LAN SRv6 X-SID sub-TLVs...............12
      7.5. IS-IS SRv6 X-SID sub-sub-TLV Codepoints Registry.........13
   8. Security Considerations.......................................13
   9. Contributors..................................................13
   10. References...................................................14
      10.1. Normative References....................................14
      10.2. Informative References..................................15
   11. Acknowledgments..............................................16



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1. Introduction

   With Segment Routing (SR)[9], a node steers a packet through an
   ordered list of instructions, called segments.

   Segments are identified through Segment Identifiers (SIDs).

   Segment Routing can be directly instantiated on the IPv6 data plane
   through the use of the Segment Routing Header defined in [10]. SRv6
   refers to this SR instantiation on the IPv6 dataplane.

   The network programming paradigm [11] is central to SRv6.

   It describes how any function can be bound to a SID and how any
   network program can be expressed as a combination of SID's.

   It defines several well-known functions such as End, End.X,
   T.Insert, T.Encaps, etc.

   This document specifies IS-IS extensions that allow IS-IS protocol
   to encode some of these functions.

   Familiarity with the network programming paradigm [11] is necessary
   to understand the extensions specified in this document.

   This document defines one new top level IS-IS_TLV and three new IS-
   IS sub-TLVs.

   The SRv6 Capabilities sub-TLV announces the ability to support SRv6
   and some functions defined in [11] as well as advertising
   limitations when applying  such functions.

   The SRv6 SID top level TLV, the P2P SRv6 X-SID sub-TLV, and the LAN
   SRv6 X-SID sub-TLV are used to advertise which SIDs are instantiated
   at a node and what function is bound to each instantiated SID.

   Only ISIS-related functions such as End and its variants D and X
   [11] are defined in this document.



   1.1. Conventions used in this document

   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 RFC-2119
   [8].




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   In this document, these words will appear with that interpretation
   only when in ALL CAPS. Lower case uses of these words are not to
   be interpreted as carrying RFC-2119 [8] significance.

2. SRv6-Capabilities sub-TLV

   As described in [10] and [11], the list of Segments is stored in the
   segment routing header referred hereafter as "SRH".

   A router that supports SRv6 MUST be able to process the segment
   routing header as described in [10] and [11] up to the limitations
   set by the advertised SRv6-capabilities sub-TLV.

   To announce this ability, a router uses the newly defined SRv6-
   capabilities sub-TLV of the router capabilities TLV [1]. The SRv6-
   capabilities sub-TLV may contain optional sub-sub-TLVs in the
   future.

   The SRv6 Capabilities sub-TLV has the following format:

   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    |            Flags              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      max-SL   |Max-End-Pop-SRH| Max-T-Ins-SRH |Max-T-Encap-SRH|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | max-End-D-SRH |
   +-+-+-+-+-+-+-+-+


      Type: Suggested value 22, to be assigned by IANA



      Length: 7 + length of sub-sub-TLVs



      Flags: 2 octets  The following flags are defined:

      0                   1
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |E|                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      where:


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        E-flag: If set, then router is able to apply "T.Encap"
        operation



      Max-SL: 1 octet.

      This field specifies the maximum value of the "SL" field [10] in
      the SRH of a received packet before applying the function
      associated with a SID.



      Max-End-Pop-SRH: 1 Octet

      This field specifies the maximum number of SIDs in the top SRH in
      an SRH stack that the router can apply "PSP" or USP" [11] flavors
      to. If the value of this field is zero, then the router cannot
      apply PSP or USP flavors.



      Max-T-Ins-SRH: 1 octet

      This field specifies the maximum number of SIDs that can be
      inserted as part of the "T.insert" behavior [11]. If the value of
      this field is zero, then the router cannot apply any variation of
      the "T.insert" behavior.



      Max-T-Encap-SRH: 1 octet

      This field specifies the maximum number of SIDs that can be
      included as part of the "T.Encap" behavior [11]. If this field is
      zero and the "E" flag is set, then the router can apply T.Encap
      by encapsulating the incoming packet in another IPv6 header
      without SRH the same way IPinIP encapsulation is performed. If
      the "E" flag is clear, then this field SHOULD be transmitted as
      zero and MUST be ignored on receipt.

      max-End-D-SRH: 1 octet

      This field specifies the maximum number of SIDs in an SRH when
      applying "End.DX6" and "End.DT6" functions. If this field is
      zero, then the router cannot apply "End.DX6" or "End.DT6"
      functions if the extension header right underneath the outer IPv6
      header is an SRH.



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3. SRv6-function Descriptor

   The SRv6 SID TLV defined in Section 4, P2P SRv6 X-SID sub-TLV
   specified in Section 6.1, and LAN SRv6 X-SID sub-TLV specified in
   section 6.2 MUST include one SRv6 function Descriptor.

   When included in the SRv6 SID TLV, the descriptor is encoded as a
   sub-TLV. When included in a P2P/LAN SRv6 X-SID sub-TLV, the
   descriptor is encoded as a sub-sub-TLV.

   The SRv6-function Descriptor encodes the function (and its flavors)
   bound to the SRv6 SID advertised in the SRv6 SID TLV [11].

   The SRv6 SID function Descriptor has the following format:

   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    | Behavior (variable) ..
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type: See IANA considerations in Section 7.

      Length: 3 * (number of functions)

      Behavior: One function (with its associated flavors) encoded in 3
      octets as shown in the following diagram

          0                   1
          0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |P|U| Reserved  |           Function              |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      The first octet encodes flags. This document defines two flags to
      specify the flavor(s) [11] associated with the SRv6 function
      specified in the "Function" field:

        P bit: If set, then the PSP flavor [11] is associated with the
        function encoded in the "function" field

        U bit: If set, then the USP flavor [11] is associated with the
        function encoded in the "function" field

        Reserved Bits SHOULD be transmitted as 0 and MUST be ignored on
        receipt.

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      The second two octets encode the function. Function code points
      are defined in Section 5.

      For a given SRv6 SID function encoded in the "Function" field,
      the "P" and "U" bits are set/cleared  according to the rules of
      enabling/disabling the PSP and USP flavors, respectively, for
      that function as specified in [11].

4. SRv6-SID TLV

   A new top level TLV is introduced to advertise SRv6 Segment
   Identifiers (SID) and their attributes.

   The new TLV is used to advertise SRv6 SIDs with any of the functions
   defined in [11] whose code point is defined in this document except
   those SIDs which must be associated with a particular neighbor in
   order to be correctly applied [11]. SRv6 SIDs associated with a
   neighbor are advertised in the sub-TLVs defined in Section 6.

   This new TLV shares the sub-TLV space defined for TLVs 135, 235, 236
   and 237.

   The SRv6 SID TLV has the following format

   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    |    flags      |   SID-size    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        SID (variable) . . .                                   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | sub-tlv-len   |         Sub-TLVs (variable) . . .             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Type: 27 (Suggested value to be assigned by IANA)

      Length: variable.

      One or more SID entries, each of which has the following format:

     Flags: 1 octet. The following flags are defined

       0
       0 1 2 3 4 5 6 7
      +-+-+-+-+-+-+-+-+
      |D| Reserved    |
      +-+-+-+-+-+-+-+-+


      where:

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        D bit: When the SID is leaked from level-2 to level-1, the D
        bit MUST be set.  Otherwise, this bit MUST be clear.  SIDs with
        the D bit set MUST NOT be leaked from level-1 to level-2.  This
        is to prevent looping.


        The remaining bits are reserved for future use. They SHOULD be
        set to zero on transmission and MUST be ignored on receipt.



      SID-Size: 1 octet. Number of bits in the SID field.

      SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
      "SID-size" field can have the values 1-128 and indicates the
      number of bits in the SID.  The SRv6 SID is encoded in the
      minimal number of octets for the given number of bits. The owning
      router may associate one or more functions as specified in [11],
      in other documents, or as locally configured.

      Sub-TLV-length: 1 octet. Number of octets used by sub-TLVs

     The function associated with the advertised SID is specified by
     the SRv6-Function Descriptor sub-TLV specified in Section 3.

5. Function Code points.

   This section defines the code points for supported functions
   associated with SRv6 SIDs. Functions are defined in [11].

   o  0: Reserved

   o  1: End Function.

   o  2: End.DX6 Function.

   o  3: End.DT6 Function.

   o  4: End.X Function.

6. Advertising SRv6 SIDs associated with a Neighbor.

   Certain SRv6 functions [11] must be associated with a particular
   neighbor, and in case of multiple layer 3 links to the same
   neighbor, with a particular link in order to be correctly applied.

   This document specifies how to advertise two such functions in IS-
   IS, namely End.X and End.DX6 [11].



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   SIDs associated with End.X and End.DX6 functions are advertised
   within neighbor reachability TLVs.

   This document defines two new sub-TLVs of TLV 22 [4], 23 [6], 222
   [5], 223[6], and 141 [7] namely "P2P SRv6 X-SID" and "LAN SRv6 X-
   SID".

   6.1. P2P SRv6 X-SID sub-TLV

   This sub-TLV is used to advertise one or more SRv6 SIDs associated
   with End.X and End.DX6 [11] functions over a point to point
   adjacency.

   The "P2P SRv6 X-SID" sub-TLV has the following format

   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    |    Flags      |   SID-size    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        SID (variable) . . .                                   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |sub-sub-tlv-len|      Sub-sub-TLVs (variable) . . .            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type: 40 (Suggested value to be assigned by IANA)

      Length: variable.



      One or more SIDs each of which has the following format:



      Flags: 1 octet. No flags defined in this document



      SID-Size: 1 octet. Number of bits in the SID field.

      SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
      "SID-size" field can have the values 1-128 and indicates the
      number of bits in the SID.  The SRv6 SID is encoded in the
      minimal number of octets for the given number of bits. The owning
      router may associate one or more functions as specified in [11],
      in other documents, or as locally configured.

      Sub-sub-TLV-length: 1 octet. Number of octets used by sub-sub-
      TLVs

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   The function associated with the advertised SID is specified by the
   SRv6-Function Descriptor sub-sub-TLV specified in Section 3. If the
   SRv6-Function Descriptor is encoded in the P2P SRv6 X-SID sub-TLV,
   then the encoded SRv6 SID function MUST include only the code points
   of SRv6 SID functions that require the specification of a neighbor
   to be correctly applied. This document specifies the code points of
   two such functions, namely End.X and End.DX6 [11].

   6.2. LAN SRv6 X-SID sub-TLV

   This sub-TLV is used to advertise one or more SRv6 SIDs associated
   with End.X and End.DX6 [11] functions over a LAN adjacency. The "LAN
   SRv6 X-SID" sub-TLV has the following format

   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    |    System ID (6 octets)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Flags       |  SID-size   |    SID (variable) . . .         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |sub-sub-tlv-len|      sub-sub-TLVs (variable) . . .            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type: 41 (Suggested value to be assigned by IANA)

      Length: variable.

      System-ID: 6 octets of IS-IS System-ID of length "ID Length" as
      defined in [2].

      One or more SIDs each of which has the following format:

      Flags 1 Octet. No flags are defined in this document

      SID-Size: 1 octet. Number of bits in the SID field.

      SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
      "SID-size" field can have the values 1-128 and indicates the
      number of bits in the SID.  The SRv6 SID is encoded in the
      minimal number of octets for the given number of bits. The owning
      router may associate one or more functions as specified in [11],
      in other documents, or as locally configured.

      Sub-sub-TLV-length: 1 octet. Number of octets used by sub-sub-
      TLVs


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   The function associated with the advertised SID is specified by the
   SRv6-Function Descriptor sub-sub-TLV specified in Section 3. If the
   SRv6-Function Descriptor is encoded in the P2P SRv6 X-SID sub-TLV,
   then the encoded SRv6 SID function MUST include only the code points
   of SRv6 SID functions that require the specification of a neighbor
   to be correctly applied. This document specifies the code points of
   two such functions, namely End.X and End.DX6 [11].

7. IANA Considerations

   This documents request allocation for the following TLVs, sub-
   TLVs,  and sub-sub-TLVs as well updating the ISIS TLV registry and
   defining a new registry.

   7.1. SRv6 SID TLV and sub-TLVs

   This document adds the following new TLV to the IS-IS TLV Codepoints
   registry.

   Value: 27 (suggested - to be assigned by IANA)

   Name: SRv6 SID

   The name of the "Sub-TLVs for TLVs 135, 235, 236 and 237 registry"
   needs to be changed to "Sub-TLVs for TLVs 27, 135, 235, 236 and 237
   registry".

   This document adds a new sub-TLV to the (renamed) "Sub-TLVs for TLVs
   27, 135, 235, 236 and 237 registry".

   Value:  5 (Suggested - to be assigned by IANA)

   Name: SRv6-function Descriptor

   The revised table of sub-TLVs in the registry should be:

   Type  27 135 235 236 237

   1     n   y   y   y   y

   2     n   y   y   y   y

   3     y   y   y   y   y

   4     y   y   y   y   y

   5(new)y   n   n   n   n

   11    y   y   y   y   y

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   12    y   y   y   y   y



   7.2. IS-IS SRv6-functions Codepoints Registry

   This document requests the creation of a new IANA managed registry
   to identify SRv6 SID functions. The registration procedure is
   "Expert Review" as defined in [3]. Suggested registry name is "SRv6
   SID Function Types". A function identifier is an unsigned 8 bits
   value. The following values are defined by this document:

   0 Reserved

   1 End function.

   2 End.DX6 function.

   3 End.DT6 function.

   4 End.X function.

   7.3. SRv6 Capabilities sub-TLV

   This document adds the definition of a new sub-TLV in the "Sub-
   TLVs for TLV 242 registry".

   Type: 22 (Suggested - to be assigned by IANA)

   Description: SRv6 Capabilities

   7.4. P2P SRv6 X-SID and LAN SRv6 X-SID sub-TLVs

   This document adds the definition of two new sub-TLVs in the "sub-
   TLVs for TLV 22, 23, 141, 222 and 223 registry".

   Type: 40 (suggested - to be assigned by IANA)

   Description: Point-to-Point SRv6 X-SID

   Type: 41 (suggested - to be assigned by IANA)

   Description: LAN SRv6 X-SID

   Type  22 23 141 222 223

   40     y  y  y   y   y

   41     y  y  y   y   y


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   7.5. IS-IS SRv6 X-SID sub-sub-TLV Codepoints Registry

   This document requests the creation of a new IANA managed registry
   to identify SRv6 SID functions encoded in P2P/LAN X-SID sub-TLVs.
   The registration procedure is "Expert Review" as defined in [3].
   Suggested registry name is "SRv6 X-SID sub-sub-TLV Codepoints
   Registry". The following values are defined by this document:

   Value:  5 (Suggested - to be assigned by IANA)

   Name: SRv6-function Descriptor

   This sub-sub-TLV MAY appear in either the Point-to-Point SRv6 X-SID
   or the LAN SRv6 X-SID sub-TLVs described in Section 7.4.

8. Security Considerations

   TBD

9. Contributors

   The following people gave a substantial contribution to the content
   of this document and should be considered as co-authors:

   Stefano Previdi (editor)
   Cisco Systems, Inc.
   Via Del Serafico, 200
   Rome  00142
   Italy

   Email: sprevidi@cisco.com


   Peter Psenak
   Cisco Systems
   Apollo Business Center Mlynske nivy 43
   Bratislava  821 09
   Slovakia

   Email: ppsenak@cisco.com


   Paul Wells
   Cisco Systems
   Saint Paul,
   Minisota,
   United States

   Email: pauwells@cisco.com


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   Daniel Voyer
   Email:  daniel.voyer@bell.ca



   Satoru Matsushima
   Email: satoru.matsushima@g.softbank.co.jp

   Bart Peirens
   Email: bart.peirens@proximus.com


   Hani Elmalky
   Email: hani.elmalky@ericsson.com


   Prem Jonnalagadda
   Email: prem@barefootnetworks.com


   Milad Sharif
   Email: msharif@barefootnetworks.com>



   Robert Hanzl
   Cisco Systems
   Millenium Plaza Building, V Celnici 10, Prague 1,
   Prague, Czech Republic
   Email rhanzl@cisco.com









10. References

   10.1. Normative References

  [1]   Previdi, S., Ginsberg, L., Chen, M., IS-IS Extensions for
        Advertising Router Information", RFC7981, October 2016




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  [2]   International Organization for Standardization, "Intermediate
        system to Intermediate system intra-domain routeing information
        exchange protocol for use inconjunction with the protocol for
        providing theconnectionless-mode Network Service (ISO 8473)",
        ISO/IEC 10589:2002, Second Edition, Nov 2002.

  [3]   T Narten and H. Alvestrand, "Guidelines for Writing an IANA
        Considerations Section in RFCs", RFC5226, May 2008

  [4]   T. Li, "IS-IS Extensions for Traffic Engineering", RFC5305,
        October 2008

  [5]   Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: MultiTopology
        (MT) Routing in Intermediate System to Intermediate Systems
        (IS-ISs)", RFC 5120, DOI 10.17487/RFC5120, February 2008,
        <http://www.rfc-editor.org/info/rfc5120>.

  [6]   McPherson, D., Ed., Ginsberg, L., Previdi, S., and M. Shand,
        "Simplified Extension of Link State PDU (LSP) Space for IS-IS",
        RFC 5311, DOI 10.17487/RFC5311, February 2009, <http://www.rfc-
        editor.org/info/rfc5311>.

  [7]   M. Chen, R. Zhang, X. Duan, "ISIS Extensions in Support of
        Inter-Autonomous System (AS) MPLS and GMPLS Traffic
        Engineering", RFC 5316, December 2008

  [8]   Bradner, S., "Key words for use in RFCs to Indicate
        Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119,
        March 1997, <http://www.rfc-editor.org/info/rfc2119>.



   10.2. Informative References

  [9]   Filsfils, C., Previdi, S., Decraene, B., Litkowski, S., and R.
        Shakir, "Segment Routing Architecture", draft-ietf-spring-
        segment-routing-11 (work in progress), Feb 2017.

  [10]  Previdi, S., Filsfils, C., Field, B., Leung, I., Linkova, J.,
        Aries, E., Kosugi, T., Vyncke, E., and D. Lebrun, "IPv6 Segment
        Routing Header (SRH)", draft-ietf-6man-segment-routing-header-
        05 (work in progress), Feb 2017.

  [11]  C. Fisfils, D. Voyer, D. Bernier, Bell Canada, D. Steinberg, R.
        Raszuk, S. Matsushima, D. Lebrun, B. Decraene, B. Peirens, S.
        Salsano, G. Naik, H. Elmalky, P. Jonnalagadda, M. Sharif, A.
        Ayyangar, Force10 Networks, A. Bashandy, K. Raza, D. Dukes, F.
        Clad, P. Camarillo, "SRv6 Network Programming", draft-filsfils-
        spring-srv6-network-programming-00 (work in progress), May 2017


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11. Acknowledgments



   This document was prepared using 2-Word-v2.0.template.dot.



Authors' Addresses



   Ahmed Bashandy
   Cisco Systems
   170 West Tasman Dr, San Jose, CA 95134, USA

   Email: bashandy@cisco.com


   Clarence Filsfils
   Cisco Systems
   Brussels, Belgium

   Email: cfilsfil@cisco.com


   Les Ginsberg
   Cisco Systems, Inc.
   US

   Email: ginsberg@cisco.com


   Bruno Decraene
   Orange
   Issy-les-Moulineaux
   FR

   Email: bruno.decraene@orange.com










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