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Versions: (RFC 4970) 00 draft-ietf-ospf-rfc4970bis

Network Working Group                                     A. Lindem, Ed.
Internet-Draft                                                   N. Shen
Obsoletes: 4970 (if approved)                                 J. Vasseur
Intended status: Standards Track                           Cisco Systems
Expires: February 1, 2015                                    R. Aggarwal
                                                                  Arktan
                                                              S. Shaffer
                                                                  Akamai
                                                           July 31, 2014


    Extensions to OSPF for Advertising Optional Router Capabilities
                   draft-acee-ospf-rfc4970bis-00.txt

Abstract

   It is useful for routers in an OSPFv2 or OSPFv3 routing domain to
   know the capabilities of their neighbors and other routers in the
   routing domain.  This document proposes extensions to OSPFv2 and
   OSPFv3 for advertising optional router capabilities.  A new Router
   Information (RI) Link State Advertisement (LSA) is proposed for this
   purpose.  In OSPFv2, the RI LSA will be implemented with a new opaque
   LSA type ID.  In OSPFv3, the RI LSA will be implemented with a new
   LSA type function code.  In both protocols, the RI LSA can be
   advertised at any of the defined flooding scopes (link, area, or
   autonomous system (AS)).  This document obsoletes RFC 4970 by
   providing a revised specification including support for advertisement
   of multiple instances of the RI LSA and a TLV for functional
   capabilities.

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 February 1, 2015.

Copyright Notice



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   Copyright (c) 2014 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
   (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
   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 . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Requirements Notation  . . . . . . . . . . . . . . . . . .  3
     1.2.  Summary of Changes from RFC 4970 . . . . . . . . . . . . .  3
   2.  OSPF Router Information (RI) LSA . . . . . . . . . . . . . . .  4
     2.1.  OSPFv2 Router Information (RI) Opaque LSA  . . . . . . . .  4
     2.2.  OSPFv3 Router Information (RI) Opaque LSA  . . . . . . . .  6
     2.3.  OSPF Router Informational Capabilities TLV . . . . . . . .  6
     2.4.  Assigned OSPF Router Informational Capability Bits . . . .  8
     2.5.  OSPF Router Functional Capabilities TLV  . . . . . . . . .  8
     2.6.  Flooding Scope of the Router Information LSA . . . . . . .  9
   3.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   4.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 12
   5.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
     5.1.  Normative References . . . . . . . . . . . . . . . . . . . 15
     5.2.  Informative References . . . . . . . . . . . . . . . . . . 15
   Appendix A.  Acknowledgments . . . . . . . . . . . . . . . . . . . 16
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17


















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1.  Introduction

   It is useful for routers in an OSPFv2 [OSPF] or OSPFv3 [OSPFV3]
   routing domain to know the capabilities of their neighbors and other
   routers in the routing domain.  This can be useful for both the
   advertisement and discovery of OSPFv2 and OSPFv3 capabilities.
   Throughout this document, OSPF will be used when the specification is
   applicable to both OSPFv2 and OSPFv3.  Similarly, OSPFv2 or OSPFv3
   will be used when the text is protocol specific.

   OSPF uses the options field in LSAs and hello packets to advertise
   optional router capabilities.  In the case of OSPFv2, all the bits in
   this field have been allocated so new optional capabilities cannot be
   advertised.  This document proposes extensions to OSPF to advertise
   these optional capabilities via opaque LSAs in OSPFv2 and new LSAs in
   OSPFv3.  For existing OSPF capabilities, backward-compatibility
   issues dictate that this advertisement is used primarily for
   informational purposes.  For future OSPF extensions, this
   advertisement MAY be used as the sole mechanism for advertisement and
   discovery.

   This document obsoletes RFC 4970 by providing a revised specification
   including support for advertisement of multiple instances of the RI
   LSA and a TLV for functional capabilities.

1.1.  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 [RFC-KEYWORDS].

1.2.  Summary of Changes from RFC 4970

   This document includes the following changes from RFC 4970 [RFC4970]:

   1.  The main change is that an OSPF router will be able to advertise
       multiple instances of the OSPF Router Information LSA.  This
       change permeates through much of the document

   2.  Additionally, Section 2.5 includes a new TLV for functional
       capabilities.  This is constast to the existing TLV which is used
       to advertise capabilities for informational purposes only.

   3.  Finally, references have been updated for drafts that have become
       RFCs and RFCs that have been obseleted since the publication of
       RFC 4970.





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2.  OSPF Router Information (RI) LSA

   OSPFv2 routers will advertise a link scoped, area-scoped, or AS-
   scoped Opaque-LSA [OPAQUE].  The OSPFv2 Router Information LSA has an
   Opaque type of 4 and Opaque ID is the instance ID.  The first
   instance ID, i.e., 0, should always contain the Router Informational
   Capabilities TLV and, if advertised, the Router Functional
   Capabilities TLV.  RI Information LSAs subsequence to the first can
   be used for information which doesn't fit in the first instance.

2.1.  OSPFv2 Router Information (RI) Opaque LSA

   OSPFv2 routers will advertise a link scoped, area-scoped, or AS-
   scoped Opaque-LSA [OPAQUE].  The OSPFv2 Router Information LSA has an
   Opaque type of 4 and Opaque ID specifies the LSA instance ID with the
   first instance always having an Instance ID of 0.


       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            LS age             |     Options   |  9, 10, or 11 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |       4       |     Opaque ID (Instance ID)                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     Advertising Router                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     LS sequence number                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         LS checksum           |             length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      +-                            TLVs                             -+
      |                             ...                               |


                   OSPFv2 Router Information Opaque LSA


   The format of the TLVs within the body of an RI LSA is the same as
   the format used by the Traffic Engineering Extensions to OSPF [TE].
   The LSA payload consists of one or more nested Type/Length/Value
   (TLV) triplets.  The format of each TLV is:








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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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              Type             |             Length            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                            Value...                           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                                TLV Format

   The Length field defines the length of the value portion in octets
   (thus a TLV with no value portion would have a length of 0).  The TLV
   is padded to 4-octet alignment; padding is not included in the length
   field (so a 3-octet value would have a length of 3, but the total
   size of the TLV would be 8 octets).  Nested TLVs are also 32-bit
   aligned.  For example, a 1-byte value would have the length field set
   to 1, and 3 octets of padding would be added to the end of the value
   portion of the TLV.  Unrecognized types are ignored.
































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2.2.  OSPFv3 Router Information (RI) Opaque LSA

   The OSPFv3 Router Information LSA has a function code of 12 while the
   S1/S2 bits are dependent on the desired flooding scope for the LSA.
   The U bit will be set indicating that the OSPFv3 RI LSA should be
   flooded even if it is not understood.  The Link State ID (LSID) value
   for this LSA is the instance ID.  The first instance ID, i.e., 0,
   should always contain the Router Informational Capabilities TLV and,
   if advertised, the Router Functional Capabilities TLV.  OSPFv3 Router
   Information LSAs subsequence to the first can be used for information
   which doesn't fit in the first instance.  OSPFv3 routers MAY
   advertise multiple RIs LSA per flooding scope.


       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            LS age             |1|S12|          12             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Link State ID (Instance ID)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Advertising Router                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       LS sequence number                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        LS checksum           |             Length             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      +-                            TLVs                             -+
      |                             ...                               |


                       OSPFv3 Router Information LSA

   The format of the TLVs within the body of an RI LSA is as defined in
   Section 2.1

   When a new Router Information LSA TLV is defined, the specification
   MUST explicitly state whether the TLV is applicable to OSPFv2 only,
   OSPFv3 only, or both OSPFv2 and OSPFv3.

2.3.  OSPF Router Informational Capabilities TLV

   The first defined TLV in the body of an RI LSA is the Router
   Informational Capabilities TLV.  An OSPF router advertising an OSPF
   RI LSA MAY include the Router Informational Capabilities TLV.  If
   included, it MUST be the first TLV in the first instance of the OSPF
   RI LSA.  Additionally, the TLV MUST accurately reflect the OSPF



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   router's capabilities in the scope advertised.  However, the
   informational capabilities advertised have no impact on the OSPF's
   operation -- they are advertised purely for informational purposes.

   The format of the Router Informational Capabilities TLV is as
   follows:


       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            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Informational Capabilities                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type     A 16-bit field set to 1.

      Length   A 16-bit field that indicates the length of the value
               portion in octets and will be a multiple of 4 octets
               dependent on the number of capabilities advertised.
               Initially, the length will be 4, denoting 4 octets of
               informational capability bits.

      Value    A variable length sequence of capability bits rounded
               to a multiple of 4 octets padded with undefined bits.
               Initially, there are 4 octets of capability bits.  Bits
               are numbered left-to-right starting with the most
               significant bit being bit 0.


                OSPF Router Informational Capabilities TLV

   The Router Informational Capabilities TLV MAY be followed by optional
   TLVs that further specify a capability.















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2.4.  Assigned OSPF Router Informational Capability Bits

   The following informational capability bits are assigned:

      Bit       Capabilities

      0         OSPF graceful restart capable [GRACE]
      1         OSPF graceful restart helper  [GRACE]
      2         OSPF Stub Router support [STUB]
      3         OSPF Traffic Engineering support [TE]
      4         OSPF point-to-point over LAN [P2PLAN]
      5         OSPF Experimental TE [EXP-TE]
      6-31      Unassigned (Standards Action)

                OSPF Router Informational Capabilities Bits

   References for [GRACE], [STUB], [TE], [P2PLAN], and [EXP-TE] are
   included herein.

2.5.  OSPF Router Functional Capabilities TLV

   This specification also defines the Router Functional Capabilities
   TLV for advertisement within the OSPF Router Information LSA.  An
   OSPF router advertising an OSPF RI LSA MAY include the Router
   Functional Capabilities TLV.  If included, it MUST be the included in
   the first instance of the LSA.  Additionally, the TLV MUST be used to
   reflect OSPF router functional capabilities.  If the TLV is not
   included or the length doesn't include the assigned OSPF functional
   capability bit, the corresponding OSPF functional capabilty is
   implicitly advertised as not being support by the advertising OSPF
   router.

   The format of the Router Functional Capabilities TLV is as follows:


















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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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Functional Capabilities                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type     A 16-bit field set to 1.

      Length   A 16-bit field that indicates the length of the value
               portion in octets and will be a multiple of 4 octets
               dependent on the number of capabilities advertised.
               Initially, the length will be 4, denoting 4 octets of
               informational capability bits.

      Value    A variable length sequence of capability bits rounded
               to a multiple of 4 octets padded with undefined bits.
               Initially, there are 4 octets of capability bits.  Bits
               are numbered left-to-right starting with the most
               significant bit being bit 0.

                  OSPF Router Functional Capabilities TLV

   The Router Functional Capabilities TLV MAY be followed by optional
   TLVs that further specify a capability.  In contrast to the Router
   Informatioal Capabilities TLV, the OSPF extensions advertised in this
   TLV MAY be used to by other OSPF routers to dicate protocol
   operation.  The specifications for functional capabilities
   adveritised in this TLV MUST describe protocol behavior and address
   backward compatibility.

2.6.  Flooding Scope of the Router Information LSA

   The flooding scope for a Router Information LSA is determined by the
   LSA type.  For OSPFv2, type 9 (link-scoped), type 10 (area-scoped),
   or a type 11 (AS-scoped) opaque LSA may be flooded.  For OSPFv3, the
   S1 and S2 bits in the LSA type determine the flooding scope.  If AS-
   wide flooding scope is chosen, the originating router should also
   advertise area-scoped LSA(s) into any attached Not-So-Stubby Area
   (NSSA) area(s).  An OSPF router MAY advertise different capabilities
   when both NSSA area scoped LSA(s) and an AS-scoped LSA are
   advertised.  This allows functional capabilities to be limited in
   scope.  For example, a router may be an area border router but only
   support traffic engineering (TE) in a subset of its attached areas.

   The choice of flooding scope is made by the advertising router and is



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   a matter of local policy.  The originating router MAY advertise
   multiple RI LSAs as long as the flooding scopes differ.  TLV flooding
   scope rules will be specified on a per-TLV basis and MUST be
   specified in the accompanying specifications for new Router
   Information LSA TLVs.














































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3.  Security Considerations

   This document describes both a generic mechanism for advertising
   router capabilities and a TLV for advertising informational and
   functional capability bits.  The capability TLVs are less critical
   than the topology information currently advertised by the base OSPF
   protocol.  The security considerations for the generic mechanism are
   dependent on the future application and, as such, should be described
   as additional capabilities are proposed for advertisement.  Security
   considerations for the base OSPF protocol are covered in [OSPF] and
   [OSPFV3].








































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4.  IANA Considerations

   The following IANA assignment was made from an existing registry:

      The OSPFv2 opaque LSA type 4 has been reserved for the OSPFv2 RI
      opaque LSA.

   The following registries have been defined for the following
   purposes:

   1.  Registry for OSPFv3 LSA Function Codes - This new top-level
       registry will be comprised of the fields Value, LSA function code
       name, and Document Reference.  The OSPFv3 LSA function code is
       defined in section A.4.2.1 of [OSPFV3].  The OSPFv3 LSA function
       code 12 has been reserved for the OSPFv3 Router Information (RI)
       LSA.

                     +-----------+-------------------------------------+
                     | Range     | Assignment Policy                   |
                     +-----------+-------------------------------------+
                     | 0         | Reserved (not to be assigned)       |
                     |           |                                     |
                     | 1-9       | Already assigned                    |
                     |           |                                     |
                     | 10-11     | Unassigned (Standards Action)       |
                     |           |                                     |
                     | 12        | OSPFv3 RI LSA (Assigned herein)     |
                     |           |                                     |
                     | 13-255    | Unassigned (Standards Action)       |
                     |           |                                     |
                     | 256-8175  | Reserved (No assignments)           |
                     |           |                                     |
                     | 8176-8183 | Experimentation (No assignments)    |
                     |           |                                     |
                     | 8184-8191 | Vendor Private Use (No assignments) |
                     +-----------+-------------------------------------+

                           OSPFv3 LSA Function Codes

       *  OSPFv3 LSA function codes in the range 256-8175 are not to be
          assigned at this time.  Before any assignments can be made in
          this range, there MUST be a Standards Track RFC that specifies
          IANA Considerations that cover the range being assigned.

       *  OSPFv3 LSA function codes in the range 8176-8181 are for
          experimental use; these will not be registered with IANA and
          MUST NOT be mentioned by RFCs.




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       *  OSPFv3 LSAs with an LSA Function Code in the Vendor Private
          Use range 8184-8191 MUST include the Vendor Enterprise Code as
          the first 4 octets following the 20 octets of LSA header.

       *  If a new LSA Function Code is documented, the documentation
          MUST include the valid combinations of the U, S2, and S1 bits
          for the LSA.  It SHOULD also describe how the Link State ID is
          to be assigned.

   2.  Registry for OSPF RI TLVs - This top-level registry will be
       comprised of the fields Value, TLV Name, and Document Reference.
       The value of 1 for the capabilities TLV is defined herein.

                     +-------------+-----------------------------------+
                     | Range       | Assignment Policy                 |
                     +-------------+-----------------------------------+
                     | 0           | Reserved (not to be assigned)     |
                     |             |                                   |
                     | 1           | Already assigned                  |
                     |             |                                   |
                     | 2-32767     | Unassigned (Standards Action)     |
                     |             |                                   |
                     | 32768-32777 | Experimentation (No assignements) |
                     |             |                                   |
                     | 32778-65535 | Reserved (Not to be assigned)     |
                     +-----------+-------------------------------------+

                                 OSPF RI TLVs

       *  Types in the range 32768-32777 are for experimental use; these
          will not be registered with IANA and MUST NOT be mentioned by
          RFCs.

       *  Types in the range 32778-65535 are reserved and are not to be
          assigned at this time.  Before any assignments can be made in
          this range, there MUST be a Standards Track RFC that specifies
          IANA Considerations that covers the range being assigned.

   3.  Registry for OSPF Router Informational Capability Bits - This
       sub-registry of the OSPF RI TLV registry will be comprised of the
       fields Bit Number, Capability Name, and Document Reference.  The
       values are defined in Section 2.4.  All Router Informational
       Capability TLV additions are to be assigned through standards
       action.

   4.  Registry for OSPF Router Functional Capability Bits - This sub-
       registry of the OSPF RI TLV registry will be comprised of the
       fields Bit Number, Capability Name, and Document Reference.



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       Initially, the sub-registry will be empty but will be available
       for future capabilities.  All Router Functional Capability TLV
       additions are to be assigned through standards action.
















































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5.  References

5.1.  Normative References

   [OPAQUE]   Berger, L., Bryskin, I., Zinin, A., and R. Coltun, "The
              OSPF Opaque LSA Option", RFC 5250, July 2008.

   [OSPF]     Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [OSPFV3]   Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
              for IPv6", RFC 5340, July 2008.

   [RFC-KEYWORDS]
              Bradner, S., "Key words for use in RFC's to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4970]  Lindem, A., Shen, N., Vasseur, J., Aggarwal, R., and S.
              Shaffer, "Extensions to OSPF for Advertising Optional
              Router Capabilities", RFC 4970, July 2007.

   [TE]       Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
              Extensions to OSPF", RFC 3630, September 2003.

5.2.  Informative References

   [EXP-TE]   Srisuresh, P. and P. Joseph, "OSPF-xTE: Experimental
              Extension to OSPF for Traffic Engineering", RFC 4973,
              July 2007.

   [GRACE]    Moy, J., Pillay-Esnault, P., and A. Lindem, "Graceful OSPF
              Restart", RFC 3623, November 2003.

   [P2PLAN]   Shen, N. and A. Zinin, "Point-to-point operation over LAN
              in link-state routing protocols", RFC 5309, October 2008.

   [STUB]     Retana, A., Nguyen, L., White, R., Zinin, A., and D.
              McPherson, "OSPF Stub Router Advertisement", RFC 6987,
              September 2013.













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Appendix A.  Acknowledgments

   The idea for this work grew out of a conversation with Andrew Partan
   and we would like to thank him for his contribution.  The authors
   would like to thanks Peter Psenak for his review and helpful comments
   on early versions of the document.

   Comments from Abhay Roy, Vishwas Manral, Vivek Dubey, and Adrian
   Farrel have been incorporated into later versions.

   The RFC text was produced using Marshall Rose's xml2rfc tool.








































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Authors' Addresses

   Acee Lindem (editor)
   Cisco Systems
   301 Midenhall Way
   Cary, NC  27513
   USA

   Email: acee@cisco.com


   Naiming Shen
   Cisco Systems
   225 West Tasman Drive
   San Jose, CA  95134
   USA

   Email: naiming@cisco.com


   Jean-Philippe Vasseur
   Cisco Systems
   1414 Massachusetts Avenue
   Boxborough, MA  01719
   USA

   Email: jpv@cisco.com


   Rahul Aggarwal
   Arktan

   Email: raggarwa_1@yahoo.com


   Scott Shaffer
   Akamai
   8 Cambridge Center
   Cambridge, MA  02142
   USA

   Email: sshaffer@akamai.com









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