rfc2641.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

   The format of the VlanHello Interswitch Keepalive message is
   described in the next section.

































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RFC 2641       Cabletron's VlanHello Protocol Version 4      August 1999


4. Interswitch Keepalive Message

   The VlanHello Interswitch Keepalive message consists of a variable
   number of octets, as shown below:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    00 |                                                               |
       +                          Frame header /                       +
       :                       ISMP packet header                      :
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     n |            Version            |      Switch IP address ...    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   n+4 |    ... Switch IP address      |                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   n+8 |                                                               |
       +                           Switch ID                           +
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  n+16 |                                                               |
       +      Chassis MAC address      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                               |      Chassis IP address ...   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  n+24 |   ... Chassis IP address      |          Switch type          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  n+28 |                        Functional level                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  n+32 |                            Options                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  n+36 |        Base MAC count         |                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
  n+40 |                                                               |
       :                        Base MAC entries                       :
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

          n = 21 + length of the authentication code of the packet


   Frame header/ISMP packet header

      This variable-length field contains the frame header and the ISMP
      packet header.






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RFC 2641       Cabletron's VlanHello Protocol Version 4      August 1999


   Version

      This 2-octet field contains the version number of the VlanHello
      protocol to which this message adheres.  This document describes
      VlanHello Version 4.

   Switch IP address

      This 4-octet field contains the Internet Protocol (IP) address of
      the sending switch.

   Switch ID

      This 10-octet field contains the internal ISMP identifier of the
      sending switch.  The identifier is generated by the sending switch
      and consists of the 6-octet physical (MAC) address of the switch,
      followed by a 4-octet value containing the logical port number
      over which the switch sent the packet.

   Chassis MAC

      This 6-octet field contains the physical (MAC) address of the
      chassis of the sending switch.

   Chassis IP address

      This 4-octet field contains the Internet Protocol (IP) address of
      the switch chassis.

   Switch type

      This 2-octet field contains the type of the switch. Currently, the
      only value recognized here is as follows:

         2   The switch is an SFVLAN switch.

   Functional level

      This 4-octet field contains the functional level of the sending
      switch, as determined by the version level of the SecureFast VLAN
      software under which this switch is operating.  Valid values are
      as follows:

         1  The switch is running a version of SFVLAN prior to Version
            1.8.
         2  The switch is running SFVLAN Version 1.8 or greater.





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RFC 2641       Cabletron's VlanHello Protocol Version 4      August 1999


   Options

      This 4-octet field contains a bit map specifying the features of
      the switch.  Bit assignments are as follows:

         1       (unused)
         2       The switch is a VLAN switch.
         4       The switch has link state capability.
         8       The switch has loop-free flood path capability.
         16      The switch has resolve capability.
         32      (unused)
         64      The switch has tag-based flood capability.
         128     The switch has tap capability.
         256     The switch has message connection capability.
         512     The switch has redundant access capability.
         1024    The switch is an isolated switch.
         4096    The switch is an uplink. (SFVLAN V1.8 only)
         8192    The switch is an uplink to core. (SFVLAN V1.8 only)
         16384   The port is an uplink port. (SFVLAN V1.8 only)
         32768   The port is an uplink flood port. (SFVLAN V1.8 only)

   Base MAC count

      This 2-octet field contains the number of entries in the list of
      Base MAC entries.

   Base MAC entries

      This variable-length field contains a list of entries for all
      neighboring switches that the sending switch has previously
      discovered on the port over which the message was sent. The number
      of entries is found in the Base MAC count field.

      Each MAC entry is 10 octets long, structured 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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      +      Switch MAC address       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                               |  Assigned neighbor state ...  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  ... Assigned neighbor state  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+







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RFC 2641       Cabletron's VlanHello Protocol Version 4      August 1999


   Switch MAC address

      This 6-octet field contains the base MAC address of the
      neighboring switch.

   Assigned neighbor state

      This 4-octet field contains the assigned state of the neighboring
      switch as perceived by the sending switch. Currently, the only
      value valid here is 3, indicating a state of Network

5. Security Considerations

   Security concerns are not addressed in this document.

6. References

   [RFC1700]   Reynolds, J. and  J. Postel, "Assigned Numbers", STD 2,
               RFC 1700, October 1994.

   [IDsfvlan]  Ruffen, D., Len, T. and J. Yanacek, "Cabletron's
               SecureFast VLAN Operational Model", RFC 2643, August
               1999.

   [IDvlsp]    Kane, L., "Cabletron's VLS Protocol Specification", RFC
               2642, August 1999.

7. Authors' Addresses

   Dave Hamilton
   Cabletron Systems, Inc.
   Post Office Box 5005
   Rochester, NH  03866-5005

   Phone:[phone]
   EMail:  [e-mail]


   Dave Ruffen
   Cabletron Systems, Inc.
   Post Office Box 5005
   Rochester, NH  03866-5005

   Phone:[phone]
   EMail:  [e-mail]






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RFC 2641       Cabletron's VlanHello Protocol Version 4      August 1999


17.  Full Copyright Statement

   Copyright (C) The Internet Society (1999).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.



















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