rfc2461.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

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RFC 2461              Neighbor Discovery for IPv6          December 1998


                      lack reflexive and transitive connectivity.

4.  MESSAGE FORMATS

4.1.  Router Solicitation Message Format

   Hosts send Router Solicitations in order to prompt routers to
   generate Router Advertisements quickly.

      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      |     Code      |          Checksum             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                            Reserved                           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Options ...
     +-+-+-+-+-+-+-+-+-+-+-+-

   IP Fields:

      Source Address
                     An IP address assigned to the sending interface, or
                     the unspecified address if no address is assigned
                     to the sending interface.

      Destination Address
                     Typically the all-routers multicast address.

      Hop Limit      255

      Authentication Header
                     If a Security Association for the IP Authentication
                     Header exists between the sender and the
                     destination address, then the sender SHOULD include
                     this header.

   ICMP Fields:

      Type           133

      Code           0

      Checksum       The ICMP checksum.  See [ICMPv6].

      Reserved       This field is unused.  It MUST be initialized to
                     zero by the sender and MUST be ignored by the
                     receiver.



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RFC 2461              Neighbor Discovery for IPv6          December 1998


   Valid Options:

      Source link-layer address
                     The link-layer address of the sender, if known.
                     MUST NOT be included if the Source Address is the
                     unspecified address.  Otherwise it SHOULD be
                     included on link layers that have addresses.

      Future versions of this protocol may define new option types.
      Receivers MUST silently ignore any options they do not recognize
      and continue processing the message.

4.2.  Router Advertisement Message Format

   Routers send out Router Advertisement message periodically, or in
   response to a Router Solicitation.

      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      |     Code      |          Checksum             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Cur Hop Limit |M|O|  Reserved |       Router Lifetime         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                         Reachable Time                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Retrans Timer                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Options ...
     +-+-+-+-+-+-+-+-+-+-+-+-

   IP Fields:

      Source Address
                     MUST be the link-local address assigned to the
                     interface from which this message is sent.

      Destination Address
                     Typically the Source Address of an invoking Router
                     Solicitation or the all-nodes multicast address.

      Hop Limit      255

      Authentication Header
                     If a Security Association for the IP Authentication
                     Header exists between the sender and the
                     destination address, then the sender SHOULD include
                     this header.



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RFC 2461              Neighbor Discovery for IPv6          December 1998


   ICMP Fields:

      Type           134

      Code           0

      Checksum       The ICMP checksum.  See [ICMPv6].

      Cur Hop Limit  8-bit unsigned integer.  The default value that
                     should be placed in the Hop Count field of the IP
                     header for outgoing IP packets.  A value of zero
                     means unspecified (by this router).

      M              1-bit "Managed address configuration" flag.  When
                     set, hosts use the administered (stateful) protocol
                     for address autoconfiguration in addition to any
                     addresses autoconfigured using stateless address
                     autoconfiguration.  The use of this flag is
                     described in [ADDRCONF].

      O              1-bit "Other stateful configuration" flag.  When
                     set, hosts use the administered (stateful) protocol
                     for autoconfiguration of other (non-address)
                     information.  The use of this flag is described in
                     [ADDRCONF].

      Reserved       A 6-bit unused field.  It MUST be initialized to
                     zero by the sender and MUST be ignored by the
                     receiver.

      Router Lifetime
                     16-bit unsigned integer.  The lifetime associated
                     with the default router in units of seconds.  The
                     maximum value corresponds to 18.2 hours.  A
                     Lifetime of 0 indicates that the router is not a
                     default router and SHOULD NOT appear on the default
                     router list.  The Router Lifetime applies only to
                     the router's usefulness as a default router; it
                     does not apply to information contained in other
                     message fields or options.  Options that need time
                     limits for their information include their own
                     lifetime fields.

      Reachable Time 32-bit unsigned integer.  The time, in
                     milliseconds, that a node assumes a neighbor is
                     reachable after having received a reachability
                     confirmation.  Used by the Neighbor Unreachability
                     Detection algorithm (see Section 7.3).  A value of



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RFC 2461              Neighbor Discovery for IPv6          December 1998


                     zero means unspecified (by this router).

      Retrans Timer  32-bit unsigned integer.  The time, in
                     milliseconds, between retransmitted Neighbor
                     Solicitation messages.  Used by address resolution
                     and the Neighbor Unreachability Detection algorithm
                     (see Sections 7.2 and 7.3).  A value of zero means
                     unspecified (by this router).

   Possible options:

      Source link-layer address
                     The link-layer address of the interface from which
                     the Router Advertisement is sent.  Only used on
                     link layers that have addresses.  A router MAY omit
                     this option in order to enable inbound load sharing
                     across multiple link-layer addresses.

      MTU            SHOULD be sent on links that have a variable MTU
                     (as specified in the document that describes how to
                     run IP over the particular link type).  MAY be sent
                     on other links.

      Prefix Information
                     These options specify the prefixes that are on-link
                     and/or are used for address autoconfiguration.  A
                     router SHOULD include all its on-link prefixes
                     (except the link-local prefix) so that multihomed
                     hosts have complete prefix information about on-
                     link destinations for the links to which they
                     attach.  If complete information is lacking, a
                     multihomed host may not be able to choose the
                     correct outgoing interface when sending traffic to
                     its neighbors.

      Future versions of this protocol may define new option types.
      Receivers MUST silently ignore any options they do not recognize
      and continue processing the message.













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RFC 2461              Neighbor Discovery for IPv6          December 1998


4.3.  Neighbor Solicitation Message Format

   Nodes send Neighbor Solicitations to request the link-layer address
   of a target node while also providing their own link-layer address to
   the target.  Neighbor Solicitations are multicast when the node needs
   to resolve an address and unicast when the node seeks to verify the
   reachability of a neighbor.

         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      |     Code      |          Checksum             |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |                           Reserved                            |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |                                                               |
        +                                                               +
        |                                                               |
        +                       Target Address                          +
        |                                                               |
        +                                                               +
        |                                                               |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |   Options ...
        +-+-+-+-+-+-+-+-+-+-+-+-

   IP Fields:

      Source Address
                     Either an address assigned to the interface from
                     which this message is sent or (if Duplicate Address
                     Detection is in progress [ADDRCONF]) the
                     unspecified address.

      Destination Address
                     Either the solicited-node multicast address
                     corresponding to the target address, or the target
                     address.

      Hop Limit      255

      Authentication Header
                     If a Security Association for the IP Authentication
                     Header exists between the sender and the
                     destination address, then the sender SHOULD include
                     this header.





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RFC 2461              Neighbor Discovery for IPv6          December 1998


   ICMP Fields:

      Type           135

      Code           0

      Checksum       The ICMP checksum.  See [ICMPv6].

      Reserved       This field is unused.  It MUST be initialized to
                     zero by the sender and MUST be ignored by the
                     receiver.

      Target Address
                     The IP address of the target of the solicitation.