path: root/doc/rfc/rfc7503.txt

Internet Engineering Task Force (IETF)                         A. Lindem
Request for Comments: 7503                                 Cisco Systems
Updates: 5340                                                   J. Arkko
Category: Standards Track                                       Ericsson
ISSN: 2070-1721                                               April 2015


                        OSPFv3 Autoconfiguration

Abstract

   OSPFv3 is a candidate for deployments in environments where
   autoconfiguration is a requirement.  One such environment is the IPv6
   home network where users expect to simply plug in a router and have
   it automatically use OSPFv3 for intra-domain routing.  This document
   describes the necessary mechanisms for OSPFv3 to be self-configuring.
   This document updates RFC 5340 by relaxing the HelloInterval/
   RouterDeadInterval checking during OSPFv3 adjacency formation and
   adding hysteresis to the update of self-originated Link State
   Advertisements (LSAs).

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7503.

















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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  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Requirements Notation . . . . . . . . . . . . . . . . . .   3
   2.  OSPFv3 Default Configuration  . . . . . . . . . . . . . . . .   4
   3.  OSPFv3 HelloInterval/RouterDeadInterval Flexibility . . . . .   5
     3.1.  Wait Timer Reduction  . . . . . . . . . . . . . . . . . .   5
   4.  OSPFv3 Minimal Authentication Configuration . . . . . . . . .   5
   5.  OSPFv3 Router ID Selection  . . . . . . . . . . . . . . . . .   5
   6.  OSPFv3 Adjacency Formation  . . . . . . . . . . . . . . . . .   6
   7.  OSPFv3 Duplicate Router ID Detection and Resolution . . . . .   6
     7.1.  Duplicate Router ID Detection for Neighbors . . . . . . .   6
     7.2.  Duplicate Router ID Detection for Non-neighbors . . . . .   7
       7.2.1.  OSPFv3 Router Autoconfiguration LSA . . . . . . . . .   7
       7.2.2.  Router-Hardware-Fingerprint TLV . . . . . . . . . . .   9
     7.3.  Duplicate Router ID Resolution  . . . . . . . . . . . . .   9
     7.4.  Change to RFC 2328, Section 13.4 ("Receiving
           Self-Originated LSAs")  . . . . . . . . . . . . . . . . .  10
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   9.  Management Considerations . . . . . . . . . . . . . . . . . .  11
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     11.2.  Informative References . . . . . . . . . . . . . . . . .  13
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15










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1.  Introduction

   OSPFv3 [OSPFV3] is a candidate for deployments in environments where
   autoconfiguration is a requirement.  This document describes
   extensions to OSPFv3 to enable it to operate in these environments.
   In this mode of operation, the protocol is largely unchanged from the
   base OSPFv3 protocol specification [OSPFV3].  Since the goals of
   autoconfiguration and security can be conflicting, operators and
   network administrators should carefully consider their security
   requirements before deploying the solution described in this
   document.  Refer to Section 8 for more information.

   The following aspects of OSPFv3 autoconfiguration are described in
   this document:

   1.  Default OSPFv3 Configuration

   2.  HelloInterval/RouterDeadInterval Flexibility

   3.  OSPFv3 Minimal Authentication Configuration

   4.  Unique OSPFv3 Router ID Generation

   5.  OSPFv3 Adjacency Formation

   6.  Duplicate OSPFv3 Router ID Resolution

   7.  Self-Originated LSA Processing

   OSPFv3 [OSPFV3] is updated by allowing OSPFv3 adjacencies to be
   formed between OSPFv3 routers with differing HelloIntervals or
   RouterDeadIntervals (refer to Section 3).  Additionally, hysteresis
   has been added to the processing of stale self-originated LSAs to
   mitigate the flooding overhead created by an OSPFv3 Router with a
   duplicate OSPFv3 Router ID in the OSPFv3 routing domain (refer to
   Section 7.4).  Both updates are fully backward compatible.

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].









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2.  OSPFv3 Default Configuration

   For complete autoconfiguration, OSPFv3 will need to choose suitable
   configuration defaults.  These include:

   1.  Area 0 Only - All autoconfigured OSPFv3 interfaces MUST be in
       area 0.

   2.  OSPFv3 SHOULD be autoconfigured on all IPv6-capable interfaces on
       the router.  An interface MAY be excluded if it is clear that
       running OSPFv3 on the interface is not required.  For example, if
       manual configuration or another condition indicates that an
       interface is connected to an Internet Service Provider (ISP),
       there is typically no need to employ OSPFv3.  In fact, [IPv6-CPE]
       specifically requires that IPv6 Customer Premise Equipment (CPE)
       routers not initiate any dynamic routing protocol by default on
       the router's WAN, i.e., ISP-facing, interface.  In home
       networking environments, an interface where no OSPFv3 neighbors
       are found, but a DHCP IPv6 prefix can be acquired, may be
       considered an ISP-facing interface, and running OSPFv3 is
       unnecessary.

   3.  OSPFv3 interfaces will be autoconfigured to an interface type
       corresponding to their Layer 2 capability.  For example, Ethernet
       interfaces and Wi-Fi interfaces will be autoconfigured as OSPFv3
       broadcast networks and Point-to-Point Protocol (PPP) interfaces
       will be autoconfigured as OSPFv3 Point-to-Point interfaces.  Most
       extant OSPFv3 implementations do this already. autoconfigured
       operation over wireless networks requiring a point-to-multipoint
       (P2MP) topology and dynamic metrics based on wireless feedback is
       not within the scope of this document.  However,
       autoconfiguration is not precluded in these environments.

   4.  OSPFv3 interfaces MAY use an arbitrary HelloInterval and
       RouterDeadInterval as specified in Section 3.  Of course, an
       identical HelloInterval and RouterDeadInterval will still be
       required to form an adjacency with an OSPFv3 router not
       supporting autoconfiguration [OSPFV3].

   5.  All OSPFv3 interfaces SHOULD be autoconfigured to use an
       Interface Instance ID of 0 that corresponds to the base IPv6
       unicast address family instance ID as defined in [OSPFV3-AF].
       Similarly, if IPv4 unicast addresses are advertised in a separate
       autoconfigured OSPFv3 instance, the base IPv4 unicast address
       family instance ID value, i.e., 64, SHOULD be autoconfigured as
       the Interface Instance ID for all interfaces corresponding to the
       IPv4 unicast OSPFv3 instance [OSPFV3-AF].




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3.  OSPFv3 HelloInterval/RouterDeadInterval Flexibility

   autoconfigured OSPFv3 routers will not require an identical
   HelloInterval and RouterDeadInterval to form adjacencies.  Rather,
   the received HelloInterval will be ignored and the received
   RouterDeadInterval will be used to determine OSPFv3 liveliness with
   the sending router.  In other words, the Neighbor Inactivity Timer
   (Section 10 of [OSPFV2]) for each neighbor will reflect that
   neighbor's advertised RouterDeadInterval and MAY be different from
   other OSPFv3 routers on the link without impacting adjacency
   formation.  A similar mechanism requiring additional signaling is
   proposed for all OSPFv2 and OSPFv3 routers [ASYNC-HELLO].

3.1.  Wait Timer Reduction

   In many situations, autoconfigured OSPFv3 routers will be deployed in
   environments where back-to-back ethernet connections are utilized.
   When this is the case, an OSPFv3 broadcast interface will not come up
   until the other OSPFv3 router is connected, and the routers will wait
   RouterDeadInterval seconds before forming an adjacency [OSPFV2].  In
   order to reduce this delay, an autoconfigured OSPFv3 router MAY
   reduce the wait interval to a value no less than (HelloInterval + 1).
   Reducing the setting will slightly increase the likelihood of the
   Designated Router (DR) flapping but is preferable to the long
   adjacency formation delay.  Note that this value is not included in
   OSPFv3 Hello packets and does not impact interoperability.

4.  OSPFv3 Minimal Authentication Configuration

   In many deployments, the requirement for OSPFv3 authentication
   overrides the goal of complete OSPFv3 autoconfiguration.  Therefore,
   it is RECOMMENDED that OSPFv3 routers supporting this specification
   minimally offer an option to explicitly configure a single password
   for HMAC-SHA authentication as described in [OSPFV3-AUTH-TRAILER].
   It is RECOMMENDED that the password be entered as ASCII hexadecimal
   digits and that 32 or more digits be accepted to facilitate a
   password with a high degree of entropy.  When configured, the
   password will be used on all autoconfigured interfaces with the
   Security Association Identifier (SA ID) set to 1 and HMAC-SHA-256
   used as the authentication algorithm.

5.  OSPFv3 Router ID Selection

   An OSPFv3 router requires a unique Router ID within the OSPFv3
   routing domain for correct protocol operation.  Existing Router ID
   selection algorithms (Appendix C.1 in [OSPFV2] and [OSPFV3]) are not
   viable since they are dependent on a unique IPv4 interface address
   that is not likely to be available in autoconfigured deployments.  An



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   OSPFv3 router implementing this specification will select a Router ID
   that has a high probability of uniqueness.  A pseudorandom number
   SHOULD be used for the OSPFv3 Router ID.  The generation SHOULD be
   seeded with a variable that is likely to be unique in the applicable
   OSPFv3 router deployment.  A good choice of seed would be some
   portion or hash of the Router-Hardware-Fingerprint as described in
   Section 7.2.2.

   Since there is a possibility of a Router ID collision, duplicate
   Router ID detection and resolution are required as described in
   Sections 7 and 7.3.  OSPFv3 routers SHOULD maintain the last
   successfully chosen Router ID in nonvolatile storage to avoid
   collisions subsequent to when an autoconfigured OSPFv3 router is
   first added to the OSPFv3 routing domain.

6.  OSPFv3 Adjacency Formation

   Since OSPFv3 uses IPv6 link-local addresses for all protocol messages
   other than messages sent on virtual links (which are not applicable
   to autoconfiguration), OSPFv3 adjacency formation can proceed as soon
   as a Router ID has been selected and the IPv6 link-local address has
   completed Duplicate Address Detection (DAD) as specified in IPv6
   Stateless Address Autoconfiguration [SLAAC].  Otherwise, the only
   changes to the OSPFv3 base specification are supporting
   HelloInterval/RouterDeadInterval flexibility as described in
   Section 3 and duplicate Router ID detection and resolution as
   described in Sections 7 and 7.3.

7.  OSPFv3 Duplicate Router ID Detection and Resolution

   There are two cases of duplicate OSPFv3 Router ID detection.  One
   where the OSPFv3 router with the duplicate Router ID is directly
   connected and one where it is not.  In both cases, the duplicate
   resolution is for one of the routers to select a new OSPFv3 Router
   ID.

7.1.  Duplicate Router ID Detection for Neighbors

   In this case, a duplicate Router ID is detected if any valid OSPFv3
   packet is received with the same OSPFv3 Router ID but a different
   IPv6 link-local source address.  Once this occurs, the OSPFv3 router
   with the numerically smaller IPv6 link-local address will need to
   select a new Router ID as described in Section 7.3.  Note that the
   fact that the OSPFv3 router is a neighbor on a non-virtual interface
   implies that the router is directly connected.  An OSPFv3 router
   implementing this specification should ensure that the inadvertent





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   connection of multiple router interfaces to the same physical link is
   not misconstrued as detection of an OSPFv3 neighbor with a duplicate
   Router ID.

7.2.  Duplicate Router ID Detection for Non-neighbors

   OSPFv3 routers implementing autoconfiguration, as specified herein,
   MUST originate an Autoconfiguration (AC) Link State Advertisement
   (LSA) including the Router-Hardware-Fingerprint Type-Length-Value
   (TLV).  The Router-Hardware-Fingerprint TLV contains a variable-
   length value that has a very high probability of uniquely identifying
   the advertising OSPFv3 router.  An OSPFv3 router implementing this
   specification MUST detect received Autoconfiguration LSAs with its
   Router ID specified in the LSA header.  LSAs received with the local
   OSPFv3 Router's Router ID in the LSA header are perceived as self-
   originated (see Section 4.6 of [OSPFV3]).  In these received
   Autoconfiguration LSAs, the Router-Hardware-Fingerprint TLV is
   compared against the OSPFv3 Router's own router hardware fingerprint.
   If the fingerprints are not equal, there is a duplicate Router ID
   conflict and the OSPFv3 router with the numerically smaller router
   hardware fingerprint MUST select a new Router ID as described in
   Section 7.3.

   This new LSA is designated for information related to OSPFv3
   autoconfiguration and, in the future, could be used for other
   autoconfiguration information, e.g., global IPv6 prefixes.  However,
   this is beyond the scope of this document.

7.2.1.  OSPFv3 Router Autoconfiguration LSA

   The OSPFv3 Autoconfiguration (AC) LSA has a function code of 15 and
   the S2/S1 bits set to 01 indicating Area Flooding Scope.  The U bit
   will be set indicating that the OSPFv3 AC LSA should be flooded even
   if it is not understood.  The Link State ID (LSID) value will be an
   integer index used to discriminate between multiple AC LSAs
   originated by the same OSPFv3 router.  This specification only
   describes the contents of an AC LSA with an LSID of 0.














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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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            LS age             |1|0|1|           15            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Link State ID                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Advertising Router                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       LS sequence number                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        LS checksum            |            Length             |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       +-                            TLVs                             -+
       |                             ...                               |

                     OSPFv3 Autoconfiguration (AC) LSA

   The format of the TLVs within the body of an AC LSA is the same as
   the format used by the Traffic Engineering Extensions to OSPFv2 [TE].
   The LSA payload consists of one or more nested TLV triplets.  The
   format of each TLV is:

       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.

   The new LSA is designated for information related to OSPFv3
   autoconfiguration and, in the future, can be used other
   autoconfiguration information.





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7.2.2.  Router-Hardware-Fingerprint TLV

   The Router-Hardware-Fingerprint TLV is the first TLV defined for the
   OSPFv3 Autoconfiguration (AC) LSA.  It will have type 1 and MUST be
   advertised in the LSID OSPFv3 AC LSA with an LSID of 0.  It SHOULD
   occur, at most, once and the first instance of the TLV will take
   precedence over subsequent TLV instances.  The length of the Router-
   Hardware-Fingerprint is variable but must be 32 octets or greater.
   If the Router-Hardware-Fingerprint TLV is not present as the first
   TLV, the AC LSA is considered malformed and is ignored for the
   purposes of duplicate Router ID detection.  Additionally, the event
   SHOULD be logged.

   The contents of the hardware fingerprint MUST have an extremely high
   probability of uniqueness.  It SHOULD be constructed from the
   concatenation of a number of local values that themselves have a high
   likelihood of uniqueness, such as Media Access Control (MAC)
   addresses, CPU ID, or serial numbers.  It is RECOMMENDED that one or
   more available universal tokens (e.g., IEEE 802 48-bit MAC addresses
   or IEEE EUI-64 Identifiers [EUI64]) associated with the OSPFv3 router
   be included in the hardware fingerprint.  It MUST be based on
   hardware attributes that will not change across hard and soft
   restarts.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              1                |             >32               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                    Router Hardware Fingerprint                |
                                      o
                                      o
                                      o
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Router-Hardware-Fingerprint TLV Format

7.3.  Duplicate Router ID Resolution

   The OSPFv3 router selected to resolve the duplicate OSPFv3 Router ID
   condition must select a new OSPFv3 Router ID.  The OSPFv3 router
   SHOULD reduce the possibility of a subsequent Router ID collision by
   checking the Link State Database (LSDB) for an OSPFv3
   Autoconfiguration LSA with the newly selected Router ID and a
   different Router-Hardware-Fingerprint.  If one is detected, a new
   Router ID should be selected without going through the resolution
   process (Section 7).  After selecting a new Router ID, all self-



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   originated LSAs MUST be reoriginated, and any OSPFv3 neighbor
   adjacencies MUST be reestablished.  The OSPFv3 router retaining the
   Router ID causing the conflict will reoriginate or flush any stale
   self-originated LSAs as described in Section 13.4 of [OSPFV2].

7.4.  Change to RFC 2328, Section 13.4 ("Receiving Self-Originated
      LSAs")

   RFC 2328 [OSPFV2], Section 13.4, describes the processing of received
   self-originated LSAs.  If the received LSA doesn't exist, the
   receiving router will flush it from the OSPF routing domain.  If the
   LSA is newer than the version in the LSDB, the receiving router will
   originate a newer version by advancing the LSA sequence number and
   reoriginating.  Since it is possible for an autoconfigured OSPFv3
   router to choose a duplicate OSPFv3 Router ID, OSPFv3 routers
   implementing this specification should detect when multiple instances
   of the same self-originated LSA are flushed or reoriginated since
   this is indicative of an OSPFv3 router with a duplicate Router ID in
   the OSPFv3 routing domain.  When this condition is detected, the
   OSPFv3 router SHOULD delay self-originated LSA processing for LSAs
   that have recently been flushed or reoriginated.  This specification
   recommends 10 seconds as the interval defining recent self-originated
   LSA processing and an exponential back-off of 1 to 8 seconds for the
   processing delay.  This additional delay should allow for the
   mechanisms described in Section 7 to resolve the duplicate OSPFv3
   Router ID conflict.

   Since this mechanism is useful in mitigating the flooding overhead
   associated with the inadvertent or malicious introduction of an
   OSPFv3 router with a duplicate Router ID into an OSPFv3 routing
   domain, it MAY be deployed outside of autoconfigured deployments.
   The detection of a self-originated LSA that is being repeatedly
   reoriginated or flushed SHOULD be logged.

8.  Security Considerations

   The goals of security and complete OSPFv3 autoconfiguration are
   somewhat contradictory.  When no explicit security configuration
   takes place, autoconfiguration implies that additional devices placed
   in the network are automatically adopted as a part of the network.
   However, autoconfiguration can also be combined with password
   configuration (see Section 4) or future extensions for automatic
   pairing between devices.  These mechanisms can help provide an
   automatically configured, securely routed network.

   In deployments where a different authentication algorithm or
   encryption is required (or different per-interface keys are
   required), OSPFv3 IPsec [OSPFV3-IPSEC] or alternate OSPFv3



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   Authentication Trailer [OSPFV3-AUTH-TRAILER] algorithms MAY be used
   at the expense of additional configuration.  The configuration and
   operational description of such deployments are beyond the scope of
   this document.  However, a deployment could always revert to explicit
   configuration as described in Section 9 for features such as IPsec,
   per-interface keys, or alternate authentication algorithms.

   The introduction, either malicious or accidental, of an OSPFv3 router
   with a duplicate Router ID is an attack point for OSPFv3 routing
   domains.  This is due to the fact that OSPFv3 routers will interpret
   LSAs advertised by the router with the same Router ID as self-
   originated LSAs and attempt to flush them from the routing domain.
   The mechanisms in Section 7.4 will mitigate the effects of
   duplication.

9.  Management Considerations

   It is RECOMMENDED that OSPFv3 routers supporting this specification
   also support explicit configuration of OSPFv3 parameters as specified
   in Appendix C of [OSPFV3].  This would allow explicit override of
   autoconfigured parameters in situations where it is required (e.g.,
   if the deployment requires multiple OSPFv3 areas).  This is in
   addition to the authentication key configuration recommended in
   Section 4.  Additionally, it is RECOMMENDED that OSPFv3 routers
   supporting this specification allow autoconfiguration to be
   completely disabled.

   Since there is a small possibility of OSPFv3 Router ID collisions,
   manual configuration of OSPFv3 Router IDs is RECOMMENDED in OSPFv3
   routing domains where route convergence due to a Router ID change is
   intolerable.

   OSPFv3 routers supporting this specification MUST augment mechanisms
   for displaying or otherwise conveying OSPFv3 operational state to
   indicate whether or not the OSPFv3 router was autoconfigured and
   whether or not its OSPFv3 interfaces have been autoconfigured.

10.  IANA Considerations

   This specification defines an OSPFv3 LSA Type for the OSPFv3
   Autoconfiguration (AC) LSA, as described in Section 7.2.1.  The value
   15 has been allocated from the existing "OSPFv3 LSA Function Codes"
   registry for the OSPFv3 Autoconfiguration (AC) LSA.








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   This specification also creates a registry for OSPFv3
   Autoconfiguration (AC) LSA TLVs.  This registry has been placed in
   the existing OSPFv3 IANA registry, and new values will be allocated
   via IETF Review or, under exceptional circumstances, IESG Approval.
   [IANA-GUIDELINES]

   Three initial values are allocated:

   o  0 is marked as Reserved.

   o  1 is Router-Hardware-Fingerprint TLV (Section 7.2.2).

   o  65535 is an Autoconfiguration-Experiment-TLV, a common value that
      can be used for experimental purposes.

11.  References

11.1.  Normative References

   [OSPFV2]   Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998,
              <http://www.rfc-editor.org/info/rfc2328>.

   [OSPFV3]   Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
              for IPv6", RFC 5340, July 2008,
              <http://www.rfc-editor.org/info/rfc5340>.

   [OSPFV3-AF]
              Lindem, A., Ed., Mirtorabi, S., Roy, A., Barnes, M., and
              R. Aggarwal, "Support of Address Families in OSPFv3", RFC
              5838, April 2010,
              <http://www.rfc-editor.org/info/rfc5838>.

   [OSPFV3-AUTH-TRAILER]
              Bhatia, M., Manral, V., and A. Lindem, "Supporting
              Authentication Trailer for OSPFv3", RFC 7166, March 2014,
              <http://www.rfc-editor.org/info/rfc7166>.

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

   [SLAAC]    Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
              Address Autoconfiguration", RFC 4862, September 2007,
              <http://www.rfc-editor.org/info/rfc4862>.






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   [TE]       Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
              (TE) Extensions to OSPF Version 2", RFC 3630, September
              2003, <http://www.rfc-editor.org/info/rfc3630>.

11.2.  Informative References

   [ASYNC-HELLO]
              Anand, M., Grover, H., and A. Roy, "Asymmetric OSPF Hold
              Timer", Work in Progress, draft-madhukar-ospf-agr-
              asymmetric-01, June 2013.

   [EUI64]    IEEE, "Guidelines for 64-bit Global Identifier (EUI-64)",
              Registration Authority Tutorial, March 1997,
              <http://standards.ieee.org/regauth/oui/tutorials/
              EUI64.html>.

   [IANA-GUIDELINES]
              Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008, <http://www.rfc-editor.org/info/rfc5226>.

   [IPv6-CPE]
              Singh, H., Beebee, W., Donley, C., and B. Stark, "Basic
              Requirements for IPv6 Customer Edge Routers", RFC 7084,
              November 2013, <http://www.rfc-editor.org/info/rfc7084>.

   [OSPFV3-IPSEC]
              Gupta, M. and N. Melam, "Authentication/Confidentiality
              for OSPFv3", RFC 4552, June 2006,
              <http://www.rfc-editor.org/info/rfc4552>.

Acknowledgments

   This specification was inspired by the work presented in the HOMENET
   working group meeting in October 2011 in Philadelphia, Pennsylvania.
   In particular, we would like to thank Fred Baker, Lorenzo Colitti,
   Ole Troan, Mark Townsley, and Michael Richardson.

   Arthur Dimitrelis and Aidan Williams did prior work in OSPFv3
   autoconfiguration in the expired Internet-Draft titled
   "Autoconfiguration of routers using a link state routing protocol".
   There are many similarities between the concepts and techniques in
   this document.

   Thanks for Abhay Roy and Manav Bhatia for comments regarding
   duplicate Router ID processing.





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   Thanks for Alvaro Retana and Michael Barnes for comments regarding
   OSPFv3 Instance ID autoconfiguration.

   Thanks to Faraz Shamim for review and comments.

   Thanks to Mark Smith for the requirement to reduce the adjacency
   formation delay in the back-to-back ethernet topologies that are
   prevalent in home networks.

   Thanks to Les Ginsberg for document review and recommendations on
   OSPFv3 hardware fingerprint content.

   Thanks to Curtis Villamizar for document review and analysis of
   duplicate Router ID resolution nuances.

   Thanks to Uma Chunduri for comments during OSPF WG last call.

   Thanks to Martin Vigoureux for Routing Area Directorate review and
   comments.

   Thanks to Adam Montville for Security Area Directorate review and
   comments.

   Thanks to Qin Wu for Operations & Management Area Directorate review
   and comments.

   Thanks to Robert Sparks for General Area (GEN-ART) review and
   comments.

   Thanks to Rama Darbha for review and comments.

   Special thanks to Adrian Farrel for his in-depth review, copious
   comments, and suggested text.

   Special thanks go to Markus Stenberg for his implementation of this
   specification in Bird.

   Special thanks also go to David Lamparter for his implementation of
   this specification in Quagga.

   This document was initially produced using the xml2rfc tool.










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Authors' Addresses

   Acee Lindem
   Cisco Systems
   301 Midenhall Way
   Cary, NC  27513
   United States

   EMail: acee@cisco.com


   Jari Arkko
   Ericsson
   Jorvas, 02420
   Finland

   EMail: jari.arkko@piuha.net


































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