[Docs] [txt|pdf] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-acee-ospf-rfc4970bis) 00 01 02 03 04 05 06 07 RFC 7770

Network Working Group                                     A. Lindem, Ed.
Internet-Draft                                                   N. Shen
Obsoletes: 4970 (if approved)                                 J. Vasseur
Intended status: Standards Track                           Cisco Systems
Expires: April 17, 2016                                      R. Aggarwal
                                                                  Arktan
                                                              S. Shaffer
                                                                  Akamai
                                                        October 15, 2015


    Extensions to OSPF for Advertising Optional Router Capabilities
                   draft-ietf-ospf-rfc4970bis-07.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.  The Router
   Information (RI) Link State Advertisement (LSA) is defined for this
   purpose.  In OSPFv2, the RI LSA will be implemented with an opaque
   LSA type ID.  In OSPFv3, the RI LSA will be implemented with a unique
   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 April 17, 2016.





Lindem, et al.           Expires April 17, 2016                 [Page 1]


Internet-Draft         OSPF Capability Extensions           October 2015


Copyright Notice

   Copyright (c) 2015 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  . . . . . . . . . . . . . . . . . . . . . . . .   2
     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 . . . . . . . .   4
     2.3.  OSPF Router Information LSA TLV Format  . . . . . . . . .   5
     2.4.  OSPF Router Informational Capabilities TLV  . . . . . . .   6
     2.5.  Assigned OSPF Router Informational Capability Bits  . . .   7
     2.6.  OSPF Router Functional Capabilities TLV . . . . . . . . .   8
     2.7.  Flooding Scope of the Router Information LSA  . . . . . .   9
   3.  Backwards Compatibility . . . . . . . . . . . . . . . . . . .   9
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
     5.1.  OSPFv2 Opaque LSA Type Assignment . . . . . . . . . . . .  10
     5.2.  OSPFv3 LSA Function Code Assignment . . . . . . . . . . .  10
     5.3.  OSPF RI LSA TLV Type Assignment . . . . . . . . . . . . .  11
     5.4.  Registry for OSPF RI Informational Capability Bits  . . .  12
     5.5.  Registry for OSPF RI Functional Capability Bits . . . . .  13
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  13
     6.2.  Informative References  . . . . . . . . . . . . . . . . .  13
   Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

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.



Lindem, et al.           Expires April 17, 2016                 [Page 2]


Internet-Draft         OSPF Capability Extensions           October 2015


   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 additional optional capabilities
   cannot be advertised.  This document describes extensions to OSPF to
   advertise these optional capabilities via opaque LSAs in OSPFv2 and
   LSAs with a unique type in OSPFv3.  For existing OSPF capabilities,
   backwards 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 an additional TLV for
       functional capabilities.  This is in contrast to the existing TLV
       which is used to advertise capabilities for informational
       purposes only.

   3.  The IANA allocation policy for the OSPFv3 LSA Function Code
       registry and all the OSPF Router Information IANA registries has
       been changed from "Standards Action" to "IETF Review"
       [IANA-GUIDE].

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





Lindem, et al.           Expires April 17, 2016                 [Page 3]


Internet-Draft         OSPF Capability Extensions           October 2015


2.  OSPF Router Information (RI) LSA

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 (RI) LSA
   has an Opaque type of 4 and the Opaque ID is the RI LSA instance ID.
   The first Opaque ID, i.e., 0, SHOULD always contain the Router
   Informational Capabilities TLV and, if advertised, the Router
   Functional Capabilities TLV.  RI LSA instances subsequent to the
   first can be used for information that doesn't fit in the first
   instance.

   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)                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+d-+-+-+-+-+-+-+-+-+-+-+
      |                     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 as defined in
   Section 2.3

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



Lindem, et al.           Expires April 17, 2016                 [Page 4]


Internet-Draft         OSPF Capability Extensions           October 2015


   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
   that doesn't fit in the first instance.  OSPFv3 routers MAY advertise
   multiple RI LSAs 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 2.3

2.3.  OSPF Router Information LSA TLV Format

   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:













Lindem, et al.           Expires April 17, 2016                 [Page 5]


Internet-Draft         OSPF Capability Extensions           October 2015


      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 4-octet
   aligned.  For example, a 1-octet 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.  The padding is composed of undefined bits.
   Unrecognized types are ignored.

   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.

2.4.  OSPF 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, i.e., instance 0, of the OSPF RI LSA.
   Additionally, the TLV MUST accurately reflect the OSPF router's
   capabilities in the scope advertised.  However, the informational
   capabilities advertised have no impact on OSPF protocol operation,
   they are advertised purely for informational purposes.

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














Lindem, et al.           Expires April 17, 2016                 [Page 6]


Internet-Draft         OSPF Capability Extensions           October 2015


       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.

2.5.  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 (IETF Review)

                OSPF Router Informational Capabilities Bits

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




Lindem, et al.           Expires April 17, 2016                 [Page 7]


Internet-Draft         OSPF Capability Extensions           October 2015


2.6.  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 reflect
   the advertising OSPF router's actual functional capabilities since
   the information will be used to dictate OSPF protocol operation in
   the flooding-scope of the containing OSPF RI LSA.  If the TLV is not
   included or the length doesn't include the assigned OSPF functional
   capability bit, the corresponding OSPF functional capability is
   implicitly advertised as not being supported by the advertising OSPF
   router.

   The format of the Router Functional 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            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Functional Capabilities                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


      Type     A 16-bit field set to IANA TBD (Suggested value 2).

      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
   Informational Capabilities TLV, the OSPF extensions advertised in
   this TLV MAY be used by other OSPF routers to dictate protocol
   operation.  The specifications for functional capabilities advertised



Lindem, et al.           Expires April 17, 2016                 [Page 8]


Internet-Draft         OSPF Capability Extensions           October 2015


   in this TLV MUST describe protocol behavior and address backwards
   compatibility.

2.7.  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
   a matter of local policy.  The originating router MAY advertise
   multiple RI LSAs with the same instance ID 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 future Router Information LSA TLVs.

3.  Backwards Compatibility

   For backwards compatibility, previously advertised Router Information
   TLVs SHOULD continue to be advertised in the first instance, i.e., 0,
   of the Router Information LSA.  If a Router Information TLV is
   advertised in multiple Router Information LSA instances and the
   multiple instance processing is not explicitly specified in the RFC
   defining that Router Information TLV, the Router Instance TLV in the
   Router Information LSA with the numerically smallest Instance ID will
   be used and subsequent instances will be ignored.

4.  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].





Lindem, et al.           Expires April 17, 2016                 [Page 9]


Internet-Draft         OSPF Capability Extensions           October 2015


5.  IANA Considerations

5.1.  OSPFv2 Opaque LSA Type Assignment

   [RFC4970] defined the Router Information opaque LSA as type 4 in the
   Opaque Link-State Advertisements (LSA) Option Types Registry.  IANA
   is asked to update the reference for that entry to point to this RFC.

5.2.  OSPFv3 LSA Function Code Assignment

   [RFC4970]  created the registry for OSPFv3 LSA Function Codes.  IANA
   is requested to update the reference for that registry to point to
   this RFC.  References within that registry to [RFC4970] should be
   updated to point to this RFC; references to other RFCs are unchanged.
   The definition and assignment policy has been updated as follows.

   This registry is now 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.  The
   assignment policy has been updated for the range 16-255.

        +-----------+-------------------------------------+
        | Range     | Assignment Policy                   |
        +-----------+-------------------------------------+
        | 0         | Reserved (not to be assigned)       |
        |           |                                     |
        | 1-11      | Already assigned                    |
        |           |                                     |
        | 12        | OSPFv3 RI LSA (Assigned herein)     |
        |           |                                     |
        | 13-15     | Already assigned                    |
        |           |                                     |
        | 16-255    | Unassigned (IETF Review)            |
        |           |                                     |
        | 256-8175  | Reserved (No assignments)           |
        |           |                                     |
        | 8176-8183 | Experimentation (No assignments)    |
        |           |                                     |
        | 8184-8190 | Vendor Private Use (No assignments) |
        |           |                                     |
        | 8191      | Reserved (not to be assigned)       |
        +-----------+-------------------------------------+

                         OSPFv3 LSA Function Codes

   o  OSPFv3 LSA function codes in the range 16-255 are to be assigned
      subject to IETF Review.  New values are assigned only through RFCs



Lindem, et al.           Expires April 17, 2016                [Page 10]


Internet-Draft         OSPF Capability Extensions           October 2015


      that have been shepherded through the IESG as AD- Sponsored or
      IETF WG Documents [IANA-GUIDE].

   o  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.

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

   o  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.

5.3.  OSPF RI LSA TLV Type Assignment

   [RFC4970] created the registry for OSPF Router Information (RI) TLVs.
   IANA is requested to update the reference for this registry to point
   to this RFC.  The definition and assignment policy has been updated
   as follows.  References within that registry to [RFC4970] should be
   updated to point to this RFC; references to other RFCs are unchanged.
   The definition and assignment policy has been updated as follows.

   The registry is now comprised of the fields Value, TLV Name, and
   Document Reference.  The value of 1 for the informational
   capabilities TLV is defined herein.  The value IANA TBD (suggested
   value 2) for the Router Functional Capabilities TLV is also defined
   herein.





















Lindem, et al.           Expires April 17, 2016                [Page 11]


Internet-Draft         OSPF Capability Extensions           October 2015


           +-------------+-----------------------------------+
           | Range       | Assignment Policy                 |
           +-------------+-----------------------------------+
           | 0           | Reserved (not to be assigned)     |
           |             |                                   |
           | 1           | Informational Capabilities        |
           |             |                                   |
           | 2           | Unassigned (IETF Review)          |
           |             |                                   |
           | TBD         | Functional Capabilities           |
           |             |                                   |
           | 3-9         | Already Assigned                  |
           |             |                                   |
           | 10-32767    | Unassigned (IETF Review)          |
           |             |                                   |
           | 32768-32777 | Experimentation (No assignments)  |
           |             |                                   |
           | 32778-65535 | Reserved (Not to be assigned)     |
           +-------------+-----------------------------------+

                               OSPF RI TLVs

   o  Types in the range 2, 10-32767 are to be assigned subject to IETF
      Review.  New values are assigned only through RFCs that have been
      shepherded through the IESG as AD-Sponsored or IETF WG Documents
      [IANA-GUIDE].

   o  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.

5.4.  Registry for OSPF RI Informational Capability Bits

   [RFC4970] created the registry for OSPF Router Informational
   Capability Bits.  IANA is requested to update the reference for this
   registry to point to this RFC.  The definition and assignment policy
   has been updated as follows.

   o  This registry is now comprised of the fields Bit Number,
      Capability Name, and Document Reference.

   o  The values are defined in Section 2.4.  All Router Informational
      Capability TLV additions are to be assigned through IETF Review
      [IANA-GUIDE].






Lindem, et al.           Expires April 17, 2016                [Page 12]


Internet-Draft         OSPF Capability Extensions           October 2015


5.5.  Registry for OSPF RI Functional Capability Bits

   IANA is asked to create a registry for OSPF Router Functional
   Capability Bits within the Open Shortest Path First v2 (OSPFv2)
   Parameters Group.  This registry will be comprised of the fields Bit
   Number, Capability Name, and Document Reference.  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 IETF Review [IANA-GUIDE].

6.  References

6.1.  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.

6.2.  Informative References

   [ENTERPRISE-CODE]
              Eronen, P. and D. Harrington, "Enterprise Number for
              Documentation Use", RFC 5612, August 2009.

   [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.






Lindem, et al.           Expires April 17, 2016                [Page 13]


Internet-Draft         OSPF Capability Extensions           October 2015


   [IANA-GUIDE]
              Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", RFC 5226, May 2008.

   [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.

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.

   Special thanks to Tom Petch for providing the updated IANA text in
   the BIS version of the document.

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

   Thanks to Yingzhen Qu for acting as document shepherd.

   Thanks to Chris Bowers, Alia Atlas, Shraddha Hegde, Dan Romascanu,
   and Victor kuarsingh for review of the BIS version of this document.

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

Authors' Addresses

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

   Email: acee@cisco.com











Lindem, et al.           Expires April 17, 2016                [Page 14]


Internet-Draft         OSPF Capability Extensions           October 2015


   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




















Lindem, et al.           Expires April 17, 2016                [Page 15]


Html markup produced by rfcmarkup 1.124, available from https://tools.ietf.org/tools/rfcmarkup/