rfc1381.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

                  STATUS  mandatory
                  DESCRIPTION
                          "The port number assigned for this link.  A
                          zero length string indicates no local port
                          number identifier has been assigned."
                  REFERENCE "ISO 8885 Table 3, Name: Port number"
                  DEFVAL { ''h }
                  ::= { lapbXidEntry 6 }

          lapbXidUserDataSubfield OBJECT-TYPE



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                  SYNTAX  OCTET STRING (SIZE (0..8206))
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "A user data subfield, if any, to be
                          transmitted in an XID frame.  A zero length
                          frame indicates no user data subfield has
                          been assigned.  The octet string should
                          include both the User data identifier and
                          User data field as shown in Figures 1 and
                          4."
                  REFERENCE "ISO 8885 section 4.3"
                  DEFVAL { ''h }
                  ::= { lapbXidEntry 7 }


          -- ###########################################################
          --                      LAPB protocol versions
          -- ###########################################################

          lapbProtocolVersion OBJECT IDENTIFIER
                  ::= { lapb 5 }

          lapbProtocolIso7776v1986 OBJECT IDENTIFIER
                  ::= { lapbProtocolVersion 1 }

          lapbProtocolCcittV1980 OBJECT IDENTIFIER
                  ::= { lapbProtocolVersion 2 }

          lapbProtocolCcittV1984 OBJECT IDENTIFIER
                  ::= { lapbProtocolVersion 3 }



          -- The following describes some of the MIB-II interface
          -- objects and their relationship with the objects in this
          -- MIB extension.

          -- ifDescr:  describes the interface.   It should include
          -- identification information for the physical line and a
          -- description of the network.  For connections to PDNs,
          -- it should name the PDN.

          -- ifMtu: the maximum number of octets an upper layer can
          -- pass to this interface as a single frame.

          -- ifSpeed:




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          -- ifAdminStatus:

          -- ifOperStatus:

          -- ifLastChange: the last time the state of the interface
          -- changed.  A reset is considered an instantaneous change to
          -- the ndm state and back to abm or abme.  This will be the
          -- last time that lapbFlowChangeReason and lapbFlowChanges
          -- changed.

          -- ifInOctets: contains the number of octets
          -- received from the peer LAPB including FCS.

          -- ifInUcastPkts: contains the number of I-frames delivered
          -- by this interface to a higher layer interface.

          -- ifInDiscards: contains the number of received
          -- frames discarded because of internal conditions
          -- (such as lack of buffering).

          -- ifInErrors: contains the number of Invalid frames received.
          -- This does not have any relationship with the number REJ,
          -- or RNR frames sent or received.

          -- ifInUnknownProtos: contains the number of frames
          -- that were correct but were dropped because they
          -- were inappropriate for the current state.  This
          -- includes an invalid Poll bit, an unknown address,
          -- or other condition such as an RNR when connection
          -- not established.  This also includes the number of
          -- DISC or other frames that were ignored because the
          -- link was not established and this interface was not
          -- configured to perform link setup on that type frame.

          -- ifOutOctets: number of octets sent to peer including
          -- FCS octets.

          -- ifOutUcastPkts: number of I-frames received from
          -- a higher layer for transmission to peer.

          -- ifOutDiscards: number of frames to be sent that were
          -- dropped due to internal conditions such as buffering etc.

          -- ifOutErrors: number of transmissions that failed
          -- due to errors or were considered invalid by the receiver.
          -- This does not have any relationship with the number REJ,
          -- or RNR frames sent or received.




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          -- ifOutQLen: number of frames waiting to be transmitted.


          -- This MIB does not provide any support for:
          --      Multilink procedure (MLP) in ISO 7776 section 6
          --      LLC Pbit timer
          --      LLC REJ timer
          --      LLC Busy State Timer 7.8.1.4

          -- ###########################################################

          END

5.  Appendix: Revision History

July 30, 1992

The July revision of this document (Editor's Internal Reference 2.10)
incorporated the comments of the SNMP directorate.

      The ifIndexType textual convention was added and used as the type
      for all index objects.

      The enumeration xidDetection of the lapbAdmnStationType was
      changed to dxe to be consistent with other similar enumerations.

      Conformance statements were added at before every table as ASN.1
      comments.

June 12, 1992

   The June 12, 1992 revision of this document (Editor's Internal
   Reference 2.9) incorporated some clarifications and updated the
   status.

      The range on PositiveInteger was changed to start at 0 rather than
      1.

      The syntax of lapbXidIndex was changed to PositiveInteger.

      A value of dxe was added to lapbOperStationType.

      The range of lapbAdmnN2RxmitCount was change to (0..65535).

      The definition of ifInOctets, ifInUcastPkts, ifInErrors,
      ifInUnknownProtos, ifOutOctets, and ifoutUcastPkts was clarified.





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May 18, 1992

   The May 18, 1992 revision of this document (Editor's Internal
   Reference  2.8) incorporated the following changes:

      The states of lapbFlowCurrentMode were redefined.

      The default value for lapbAdmnControlField was changed from
      module8 to modulo8.

April 8, 1992

   The April 8, 1992 revision of this document (Editor's Internal
   Reference 2.4) incorporated the following changes:

      All reference comments in the MIB were moved to the REFERENCE
      field of the OBJECT-TYPE macro.

      A type of PositiveInteger was introduced and used for common
      integer values including all timers.  This effectively made the
      maximum value for timers 2147483646 milliseconds.  The type of the
      frame size was changed to positiveInteger.

      The reference to ISO 7776 has been broadened to say the MIB
      descriptions use the terminology of ISO 7776.

      A comment was added to the overview section discussing creation
      and deletion of tables.

      The objects in the lapbParmTable and lapbDefTable were
      redistributed to create a lapbOperTable, a lapbAdmnTable, and a
      lapbXidTable.  The lapbParmTable and lapbDefTable were deleted.
      Objects were included in the Admn table for t3 and t4.

      An object identifier was added to identify the protocol version.

      A DEFVAL clause was added for all writable objects.

      Some more overview text was included.

February 1992

   The February 1992 revision of this document (Editor's Internal
   Reference 1.17) incorporated the following changes:

      The name was changed from HDLC to LAPB. This change was made
      because other flavors of HDLC such as LAPD, SDLC, and raw HDLC
      framing, are different enough that this MIB will not adequately



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      manage them.

      The Historical Perspective section at the beginning of the
      document has been replaced with a more concise Network Management
      Framework section.

      The name lapbParmKWindowSize was changed to
      lapbParmTransmitKWindowSize and the object
      lapbParmReceiveKWindowSize was added. This change was made because
      section 5.7.4 of ISO 7776 and Table 3 of ISO 8885 have provisions
      for different values for the transmit and receive window size.

      The name lapbParmN1FrameSize was changed to
      lapbParmTransmitN1FrameSize and the object
      lapbParmReceiveN1FrameSize was added. This change was made because
      section 5.7.3 of ISO 7776 and Table 3 of ISO 8886 have provisions
      for different values for the transmit and receive maximum frame
      size.

      The object lapbParmPortIndex was deleted and the description of
      lapbParmPortId was changed.  The object lapbParmPortId now
      identifies an instance of the index object for the MIB of the
      physical device or interface below LAPB.

      The units for the timers were changed to Milliseconds to be
      consistent with ISO 8885; see table 3.

      The objects lapbParamT2AckDelayTimer and
      lapbParamT3DisconnectTimer both allow values of 0 to indicate the
      timer is not being used.

      The object lapbParamT4IdleTimer has a value to indicate timer not
      in use.

      The object lapbFlowXidReceived was added to the flow table.

      The lapbDefTable was added.

      Ranges and sizes were added for all INTEGERs and OCTET STRINGs
      that didn't have them.

October 1991

   The October 1991 revision of this document basically changed the name
   from LAPB to HDLC to make the objects more appropriate for a broader
   range of uses.  A number of minor changes were made to bring the
   objects in line with established conventions.  These changes are as
   follows.



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      The enumerated values of hdlcParmStationType were renumbered from
      0 and 1 to 1 and 2.

      The object hdlcFlowBusyDefer was renamed hdlcFlowBusyDefers.

      The object hdlcFlowRejSent was rename hdlcFlowRejOutPkts.

      The object hdlcFlowRejReceived was renamed hdlcFlowRejInPkts.

June 1991

   The June revision of this document incorporated much of the E-mail
   discussion of the first draft. In particular it replaced the
   lapbStatTable (and all contents) with the lapbFlowTable.

April 1991

   The April 24 version of this document was the first release.  At that
   time this document was basically a bunch of objects synthesized from
   various vendor MIBs and a quick reading of ISO 7776 [10].  On first
   reading it appeared to instrument too many LAPB normal functions and
   too few exceptional conditions.  The lapbStatTable was too long and
   needed to be redone.

6.  Acknowledgements

   This document was produced by the x25mib working group:

                  Fred Baker, ACC
                  Art Berggreen, ACC
                  Frank Bieser