rfc2443.txt

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RFC 2443                MARS Service Using SCSP            November 1998


4.  Values for SCSP Protocol Independent Part

   The following sections give values for fields of the SCSP Protocol
   Independent Part of the various SCSP messages.

4.1 Values for the SCSP "Mandatory Common Part"

   Protocol ID = 0x0003
   Sender ID Len = 0x04
   Recvr ID Len = 0x04

   See Section B.2.0.1 of [2] for a detailed description of these
   fields.

4.2 Values for the SCSP "CSAS Record"

   Cache Key Len = 0x04
   Orig ID Len = 0x04

   See Section B.2.0.2 of [2] for a detailed description of these
   fields.

5.  Detailed State Descriptions

5.1  MARS Server Redirect Entry.

   The MARS Server Redirect Entry is used to determine the operational
   state of a MARS Server in the SG. Each server MUST update it's MARS
   Server Redirect Entry state at least every 2 minutes, it is
   RECOMMENDED that it is updated every 1 minute.

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Hardware Type          |        Protocol Type          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              SNAP                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     SNAP      |   Unused      |    Version    |   State       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Flags              |       Cluster Member ID       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Src Addr Len  | Group Addr Len| ATM Addr T/L  |ATM SubAddr T/L|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM Address                  (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM SubAddress               (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



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RFC 2443                MARS Service Using SCSP            November 1998


   Hardware Type
     This value is the ATM Forum 'address family number' specified in
     [3] as 15 decimal (0x000F).

   Protocol Type
     This field is the protocol type number for the protocol using MARS
     from [3].  (IPv4 is 0x0800).

   Protocol SNAP
     This field is the optional protocol SNAP extension to protocol
     type.  This is the mar$pro.snap field from [1].

   Version Number
     Version Number for this document MUST be set to 0x00.

   State
     State value is coded as 1 decimal for a MARS Server Redirect Entry.

   The Flags, Cluster Member ID, Src Addr Len, and Group Addr Len fields
   are unused and set to zero.

   The ATM Addr T/L, ATM SubAddr T/L, Source ATM Address, and Source ATM
   SubAddress fields define the ATM address for the source of the MARS
   Server Redirect Entry in the SG. The coding for these fields are the
   same as described in Section 3 of this document.

   Failure to receive two consecutive MARS Server Redirect Entry updates
   from a given MARS Server in the SG will cause all membership
   information learned from this server to be flushed. When a valid MARS
   Server Redirect Entry update is received the source of this update
   will be placed into the table of backup MARS Servers sent in the
   MARS_REDIRECT_MAP message. The ordering of servers in the
   MARS_REDIRECT_MAP will first contain the list of MARS Servers learned
   via MARS Server Redirect Entry updates in ascending order based on
   the SCSP Sender ID, followed by any externally configured or learned
   backup MARS Servers. The format of the MARS_REDIRECT_MAP can be found
   in Section 5.4.3 of [1].

5.2  MCS Serve/Register request.

   The MCS Serve/Register request is used to propagate the registering
   or servicing of specific groups by an MCS Client within the SG
   domain. It is similar to an MARS_MSERV request defined in Section
   6.2.2 and 6.2.3 of [1]. When a MARS Server in the SG successfully
   adds a new MCS Client to it's SCVC or adds MCS support for a specific
   group it MUST send a MCS Serve/Register request to the SG. An MCS
   Client can only register with one MARS Server in the SG.




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RFC 2443                MARS Service Using SCSP            November 1998


   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Hardware Type          |        Protocol Type          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              SNAP                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     SNAP      |   Unused      |    Version    |   State       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Flags              |       Cluster Member ID       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Src Addr Len  | Group Addr Len| ATM Addr T/L  |ATM SubAddr T/L|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source Protocol Address             (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM Address                  (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM SubAddress               (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Minimum Multicast Group Address     (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Maximum Multicast Group Address     (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Hardware Type
     This value is the ATM Forum 'address family number' specified in
     [3] as 15 decimal (0x000F).

   Protocol Type
     This field is the protocol type number for the protocol using MARS
     from [3].  (IPv4 is 0x0800).

   Protocol SNAP
     This field is the optional protocol SNAP extension to protocol
     type.  This is the mar$pro.snap field from [1].

   Version Number
     Version Number for this document MUST be set to 0x00.

   State
     State value is coded as 2 decimal for a MCS Serve/Register request.

   Flags
     The flags field is used to contain several flags:







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RFC 2443                MARS Service Using SCSP            November 1998


       mar$flags
          Bit 15   - mar$flags.layer3grp
          Bit 13   - mar$flags.register
          Bit 0-7  - mar$flags.sequence

     The mar$flags.register bit MUST be set the same as in the
     originating MARS_MSERV request. The mar$flags.layer3grp bit MUST be
     zero and the mar$flags.sequence bits are of local significance only
     to the LS.

   Cluster Member CMI
     This field contains the CMI assigned by the MARS Server which
     processed the MARS_MSERV request and uniquely identifies the MCS
     Client in the MARS server cache.

   Src Addr Len
     This field contains the length of the Source Protocol Address
     field.  For IPv4, the value is 4 if an address is specified. A null
     (non-existent) address MUST be coded as zero length, and no space
     allocated for it in the message body.

   Group Addr Len
     This field contains the length of the Group Protocol Address field.
     If the register bit in the flags field is set to 1 in the request
     this field MUST be zero.  If the register bit is zero in the flags
     field the value of this field for IPv4 is 4.

   ATM Addr T/L
     This field contains the type and length of the Source ATM Address
     field for the MCS Client that originated the MARS_MSERV request.
     The type and length encoding is described in Section 3.

   ATM SubAddr T/L
     This field contains the type and length of the Source ATM
     SubAddress field for the MCS Client that originated the MARS_MSERV
     request.  The type and length encoding is described in Section 3.

   Source Protocol Address
     This is the internetwork address for the source of an address
     binding in a MARS server cache entry. If Src Addr Len is set to
     zero no storage will be allocated.

   Source ATM Address
     This is the MCS Client's ATM address of an address binding in a
     MARS server cache entry. The address is E.164 or ATM Forum NSAPA.






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   Source ATM SubAddress
     This is the MCS Client's ATM subaddress of an address binding in a
     MARS server cache entry. The subaddress, if specified, is an ATM
     Forum NSAPA.  If null, no storage will be allocated.

   Minimum Multicast Group Address
     This is the internetwork address of the lower bound on the range of
     multicast group addresses for the address binding in a MARS server
     cache entry. If Group Addr Len is set to zero no storage will be
     allocated.

   Maximum Multicast Group Address
     This is the internetwork address of the upper bound on the range of
     multicast group addresses for the address binding in a MARS server
     cache entry. If Group Addr Len is set to zero no storage will be
     allocated.

   An MCS Client can only register with one MARS Server in the SG and is
   only placed on the SCVC for the MARS Server for which it is
   registered with.

   When a MCS Client Serve/Register request specifying a group address
   is received by a MARS Server it MUST create a cache entry associated
   with this client. In addition to adding the cache entry it MUST send
   out a MARS_MIGRATE message on it's CCVC. This is needed so that
   clients using a mesh topology can migrate to a server based topology.
   Details regarding the MARS_MIGRATE message can be found in Section
   5.1.6 of [1].

5.3  MARS Client Join/Register request.

   The MARS Client Join/Register request is used to propagate the
   registering or joining of specific group ranges by MARS Clients
   within the SG domain.  It is similar to the MARS_JOIN request defined
   in Sections 5.2.1 to 5.2.3 of [1]. When a MARS Server in the SG
   successfully registers a new MARS Client or a registered client joins
   a specific group address range the MARS Server MUST send a MARS
   Client Join/Register request to the SG. A MARS Client can only
   register with one MARS Server in the SG and is placed only on that
   servers CCVC.











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RFC 2443                MARS Service Using SCSP            November 1998


   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Hardware Type          |        Protocol Type          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              SNAP                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     SNAP      |   Unused      |    Version    |   State       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Flags              |       Cluster Member ID       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Src Addr Len  | Group Addr Len| ATM Addr T/L  |ATM SubAddr T/L|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source Protocol Address             (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM Address                  (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Source ATM SubAddress               (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Minimum Multicast Group Address     (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Maximum Multicast Group Address     (variable length)     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Hardware Type
     This value is the ATM Forum 'address family number' specified in
     [3] as 15 decimal (0x000F).

   Protocol Type
     This field is the protocol type number for the protocol using MARS
     from [3].  (IPv4 is 0x0800).

   Protocol SNAP
     This field is the optional protocol SNAP extension to protocol
     type.  This is the mar$pro.snap field from [1].

   Version Number
     Version Number for this document MUST be set to 0x00.

   State
     State value is coded as 3 decimal for a MARS Client Join/Register
     request.









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RFC 2443                MARS Service Using SCSP            November 1998