rfc2124.txt

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   is as shown for Destination Address IE.

Destination Switch Address IE

   Destination Switch address associated with a message. TYPE is 16,
   format is as shown for Destination Address IE.

Time IE

   The time (as a SNMPv2 TimeStamp [1443]) associated with the
   status/statistics observed. TYPE is 17 and format 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 = 17           |          LENGTH = 4           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              Time                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+








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RFC 2124                          LFAP                       March 1997


Multiple Record IE

   The Multiple Record IE is composed of 4 parts.  The record
   descriptor, fixed information, record format IEs and individual
   records.  The record descriptor consist of two fields the first field
   is the length of the fixed information field.  The second is the
   length of the Record format section.  The fixed information is the
   IE's that apply to all the records that follow. The Record Format is
   the list of IE's that make up each record. The individual record
   section contains the individual records that are being reported in
   the format given by the Record Format section.

    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 = 18           |          LENGTH               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Length of fixed Information  |   Length of Record Format     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                     Fixed Information                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                       Record Format                           ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                    Individual Record (1)                      |
   |                    Individual Record (2)                      |
   |                    Individual Record (3)                      |
   |                             .                                 |
   ~                             .                                 ~
   |                             .                                 |
   |                    Individual Record (n)                      |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+














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RFC 2124                          LFAP                       March 1997


Flow Failure Code IE

   Flow failure code is the reason why a operation an a given flow
   failed. IE format 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 = 19           |          LENGTH = 4           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Flow Failure Code                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


  Flow failure code has one of the following values and meanings:

     0 - POLICY_REJECT        - A policy reject has occurred
     1 - NO_SUCH_FLOW         - The specified was flow was not found
     2 - AMBIGUOUS            - Duplicate FAR caused this error
     3 - DESTINATION_UNKNOWN  - The redirect destination was unknown

Command Code IE

   Command Code is a administrative request command to perform a
   particular function. IE format 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 = 20           |          LENGTH = 4           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Command  Code                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


  Command code has one of the following values and meanings:

     0 - RETURN_INDICATED_FLOWS    - Return FUNs indicated
     1 - RETURN_ALL_CHANGED_FLOWS  - Return FUNs indicated
     2 - RETURN_ALL_FLOWS          - Return FUNs indicated
     3 - RETURN_FLOW_PREFIX        - Return a new flow prefix










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RFC 2124                          LFAP                       March 1997


Flow Identifier Prefix IE

   The flow Identifier prefix IE gives the prefix that the FAS has
   created to maintain a globally unique ID. IE format 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 = 21           |          Length = 8           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |+-+-+-+-+-   FAS assigned Flow Identifier Prefix      -+-+-+-+-+
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.2.  Flow Admission Request (FAR) Message

   Status is set to SUCCESS in FAR messages. In addition, FAR messages
   may contain the following IEs:

      Source Switch Address IE  - address of switch making request
      Dest Switch Address IE    - address of switch to which the
                                  request is made
      Source Address IE         - flow "from" address
      Destination Address IE    - flow "to" address
      Service Identifier IE     - identifier for service requested
      Flow ID IE                - locally unique identifier for flow
                                  (unique to update reporting entity)
      Client Data IE            - client data as applied to this request
      Time IE                   - switch time of admission request

   Mandatory IE's
      Source Address
      Destination Address
      Flow ID
      Time

   Optional IE's
      Source Switch Address
      Destination Switch Address
      Client Data










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RFC 2124                          LFAP                       March 1997


   FAR messages are sent by a switch CCE when it seeks verification of
   validity of a flow that is about to be established. FAR messages
   refer to a single flow only and do not multi IE functionality. Source
   and destination addresses are those determined by the switch CCE as
   the points of origin and termination of a flow. Service ID is the
   service type/category associated with the desired flow. The client
   data is arbitrary information about the client associated with the
   desired flow.

3.3.  Flow Admission Acknowledge (FAA) Message

   Status reflects the result of the corresponding FAR message (see
   Error Handling for details). Message ID is copied from the FAR
   message. In addition, FAA messages may have the following IEs:

      Optional Operating Policy IE  - policy(s) that may apply to
                                      this flow.
      Mandatory Operating Policy IE - policy(s) that must apply to
                                      this flow.

      Destination Address IE        - may be included if the flow
                                      should be redirected.
      Flow Failure Code IE          - indicates the cause of flow
                                      failure

   FAA messages are sent by a FAS in response to FAR messages received
   from a switch CCE. Operating policy information is that determined by
   the FAS as either desirable or required for the flow specified in the
   corresponding FAR message.

3.4.  Flow Admission Update (FAU) Message

   Status reflects the result of the corresponding FAA message (see
   Error Handling for details).  Message ID is copied from the FAR or
   FAA message. In addition, FAU messages may have the following IEs:

      Flow ID IE           - identifier for the flow
      Flow Failure Code IE - indicates the cause of flow failure

   FUA messages are sent by a switch CCE in response to FAA messages
   received from a FAS.  The FAU message is returned by the switch CCE
   only if an a error was detected as a result of the FAA message.









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RFC 2124                          LFAP                       March 1997


3.5.  Flow Update Notification (FUN) Message

   Status is set to SUCCESS in FUN messages.  In addition, FUN messages
   may contain the following IEs:

      Time IE         - switch time of notification
      Flow ID IE      - identifier for the flow
      Flow State IE   - state of the flow at time of notification
      Byte Count IE   - octets sent and received for this flow
      Packet Count IE - packets sent and received for this flow

   Mandatory IE's
      Time - If multiple IE, only needs to be given once in fixed
             information section. If given in record format must be
             in each individual record.

   Optional IE's at least one must be present
      Flow State
      Byte Count
      Packet Count

   FUN messages are sent periodically (possibly as specified in an
   operating policy associated with the flow) by an CCE to the FAS. The
   Time IE may be given first and only once. If it is only a single flow
   being reported on then just the IE's and their values are returned.
   If multiple flows are to be reported on then the multiple record IE
   should be used. This results in reduced overhead on transmissions.
   FUN messages may are also be sent as a result of a AR message or a
   FCR message. The FCR message would be one that request that the flow
   state be set to inactive.

   The flow ID identifies the flow to which this update applies.  Flow
   state is the state of the flow at the time this message is sent.
   Counts are as specified in the IE definitions.  The FAS's are
   coordinated and will resolve the reception of FUN information from a
   CCE who has lost connection with its FAS and has gone to a
   alternative FAS.

3.6.  Flow Update Acknowledge (FUA) Message