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rfc:rfc1381

Network Working Group D. Throop Request for Comments: 1381 Data General Corporation

                                                              F. Baker
                                      Advanced Computer Communications
                                                         November 1992
                  SNMP MIB Extension for X.25 LAPB

Status of this Memo

 This RFC specifies an IAB standards track protocol for the Internet
 community, and requests discussion and suggestions for improvements.
 Please refer to the current edition of the "IAB Official Protocol
 Standards" for the standardization state and status of this protocol.
 Distribution of this memo is unlimited.

Abstract

 This memo defines a portion of the Management Information Base (MIB)
 for use with network management protocols in TCP/IP-based internets.
 In particular, it defines objects for managing the Link Layer of
 X.25, LAPB.  The objects defined here, along with the objects in the
 "SNMP MIB Extension for the Packet Layer of X.25" [9] and the
 "Definitions of Managed Objects for RS-232-like Hardware Devices"
 [8], combine to allow management of an X.25 protocol stack.

Table of Contents

 1. The Network Management Framework .......................    2
 2. Objects ................................................    2
 2.1 Format of Definitions .................................    3
 3. Overview ...............................................    3
 3.1 Informal overview .....................................    3
 3.2 Textual Conventions ...................................    4
 3.3 Formal overview .......................................    4
 3.4 Tables ................................................    5
 3.5 Traps .................................................    6
 4. Object Definitions .....................................    6
 5. Appendix: Revision History .............................   27
    July 30, 1992 ..........................................   27
    June 12, 1992 ..........................................   27
    May 18, 1992 ...........................................   28
    April 8, 1992 ..........................................   28
    February 1992 ..........................................   28
    October 1991 ...........................................   29
    June 1991 ..............................................   30
    April 1991 .............................................   30

Throop & Baker [Page 1] RFC 1381 X.25 LAPB MIB November 1992

 6. Acknowledgements .......................................   30
 7. References .............................................   31
 8. Security Considerations ................................   33
 9. Authors' Addresses .....................................   33

1. The Network Management Framework

 The Internet-standard Network Management Framework consists of three
 components.  These components give the rules for defining objects,
 the definitions of objects, and the protocol for manipulating
 objects.
 The network management framework structures objects in an abstract
 information tree. The branches of the tree name objects and the
 leaves of the tree contain the values manipulated to effect
 management. This tree is called the Management Information Base or
 MIB. The concepts of this tree are given in STD 16/RFC 1155 "The
 Structure of Management Information" or SMI [1]. The SMI defines the
 trunk of the tree and the types of objects used when defining the
 leaves. STD 16/RFC 1212, "Towards Concise MIB Definitions" [4],
 defines a more concise description mechanism that preserves all the
 principals of the SMI.
 The core MIB definitions for the Internet suite of protocols can be
 found in RFC 1156 [2] "Management Information Base for Network
 Management of TCP/IP-based internets". STD 17/RFC 1213 [5] defines
 MIB-II, an evolution of MIB-I with changes to incorporate
 implementation experience and new operational requirements.
 STD 15/RFC 1157 [3] defines the SNMP protocol itself. The protocol
 defines how to manipulate the objects in a remote MIB.
 The tree structure of the MIB allows new objects to be defined for
 the purpose of experimentation and evaluation.

2. Objects

 The definition of an object in the MIB requires an object name and
 type.  Object names and types are defined using the subset of the
 Abstract Syntax Notation One (ASN.1) [6] defined in the SMI [1].
 Objects are named using ASN.1 object identifiers, administratively
 assigned names, to specify object types. The object name, together
 with an optional object instance, uniquely identifies a specific
 instance of an object. For human convenience, we often use a textual
 string, termed the OBJECT DESCRIPTOR, to also refer to objects.
 Objects also have a syntax that defines the abstract data structure
 corresponding to that object type.  The ASN.1 language [6] provides

Throop & Baker [Page 2] RFC 1381 X.25 LAPB MIB November 1992

 the primitives used for this purpose.  The SMI [1] purposely
 restricts the ASN.1 constructs which may be used for simplicity and
 ease of implementation.  The encoding of an object type simply
 describes how to represent an object using ASN.1 encoding rules [7],
 for purposes of dealing with the SNMP protocol.

2.1. Format of Definitions

 Section 4 contains the specification of all object types defined in
 this MIB module. The object definitions use the conventions given in
 the SMI [1] as amended by the concise MIB definitions [4].

3. Overview

3.1. Informal overview

 This section describes how the objects defined below relate with
 other MIBs.  This section is only informational to help understand
 how the pieces fit together.
 The objects defined below are to be used in conjunction with MIB-II
 and other MIBs such as the X.25 packet level MIB [9].  A system with
 a complete X.25 stack running over a synchronous line will have at
 least two interfaces in the ifTable defined in MIB-II.  There will be
 an interface for LAPB and another interface for the packet layer of
 X.25. There will also be objects defined in the RS-232-like MIB for
 the physical sync line.
 Each software interface identifies the layer below it used to send
 and receive packets. The X.25 MIB object, x25InfoDataLinkId,
 specifies an instance of lapbAdmnIndex for the LAPB interface under
 that X.25. The LAPB object, lapbOperPortId, defined below, identifies
 an instance of the rs232PortIndex for the the Sync line used by LAPB.
 For X.25 running over LAPB over Ethernet, the lapbAdmnPortId would
 identify the instance of ifIndex for the Ethernet interface.
 Each X.25 subnetwork will have separate entries in the ifTable.  Thus
 a system with two X.25 lines would have two ifTable entries for the
 two X.25 packet layers and two other entries for the two LAPB
 interfaces. Each X.25 Packet Layer MIB would identify the instance of
 the LAPB MIB below it. Each LAPB MIB would identify the Sync line
 below it. The system would also have two entries for rs232PortTable
 and rs232SyncPortTable for the two physical lines.
 Since the ifTable as defined in MIB-II is device independent, it
 doesn't have anything specific for any type of interface.  The
 objects below define the LAPB specific information for an interface

Throop & Baker [Page 3] RFC 1381 X.25 LAPB MIB November 1992

 of type LAPB. Different LAPB interfaces can also be differentiated by
 matching the values of ifIndex with lapbAdmnIndex.

3.2. Textual Conventions

 Two new data types are introduced as a textual conventions in this
 MIB document.  These textual conventions enhance the readability of
 the specification and can ease comparison with other specifications
 if appropriate.  It should be noted that the introduction of these
 textual conventions has no effect on either the syntax nor the
 semantics of any managed objects.  The use of these is merely an
 artifact of the explanatory method used.  Objects defined in terms of
 one of these methods are always encoded by means of the rules that
 define the primitive type.  Hence, no changes to the SMI or the SNMP
 are necessary to accommodate these textual conventions which are
 adopted merely for the convenience of readers and writers in pursuit
 of the elusive goal of clear, concise, and unambiguous MIB documents.
 This MIB introduces the data types of:
                  PositiveInteger
                  ifIndexType

3.3. Formal overview

 Instances of the objects defined below represent attributes of a LAPB
 interface.  LAPB interfaces are identified by an ifType object in the
 Internet-standard MIB [5] of
              lapb(16).
 For these interfaces, the value of the ifSpecific variable in the
 MIB-II [5] has the OBJECT IDENTIFIER value:
              lapb    OBJECT IDENTIFIER ::= { transmission 16 }
 The relationship between a LAPB interface and an interface in the
 context of the Internet-standard MIB [5] is one-to-one.  As such, the
 value of an ifIndex object instance can be directly used to identify
 corresponding instances of the objects defined below.
 The objects defined below are defined in the context of ISO 7776 [10]
 and ISO 8885 [11]. Access to those documents maybe useful (but isn't
 essential) to understand the names and semantics of some objects.
 Where possible the object descriptions use the terminology of ISO
 7776; for example, one commonly used term refers to the peer LAPB as
 the DCE/remote DTE.  This terminology does not restrict the
 instrumented LAPB to function only as a DTE.  This MIB maybe applied

Throop & Baker [Page 4] RFC 1381 X.25 LAPB MIB November 1992

 to a LAPB configured as either a DCE or a DTE.
 To the extent that some attributes defined in the Internet standard
 MIB [5] are applicable to LAPB, those objects have not been
 duplicated here.  In some instances some clarification of how to
 apply those objects to LAPB has been given.
 Some objects defined below include a DEFVAL clause. This clause
 provides reasonable (but not mandatory) default values to use when
 creating these objects.  This does not imply this MIB defines any
 mechanism for creating or deleting LAPB interfaces.  The creation and
 deletion of the objects of this MIB depend on the implementation
 method for creating and deleting LAPB interfaces.  The DEFVAL clause
 provides reasonable defaults to allow further extension of the MIB to
 define methods for creating and deleting LAPB interfaces without
 having to deprecate these objects for the lack of a DEFVAL clause.

3.4. Tables

 This extension adds four tables to the MIB.  These tables are:
                     lapbAdmnTable,
                     lapbOperTable,
                     lapbFlowTable, and
                     lapbXidTable.
 The lapbAdmnTable provides objects for common parameters used by LAPB
 such as the T1 retransmission timer or the N2 retransmission counter.
 Changes to objects in this table need not affect a running interface
 but provides access to the values used to initialize an interface.
 These values are read-write.
 The lapbOperTable provides objects to determine the parameters
 actually in use by an interface.  These objects are read only.  The
 values currently in use maybe different from the lapbAdmnTable values
 if the lapbAdmnTable was changed after interface initialization or if
 XID negotiation selected different values.
 The lapbFlowTable provides objects that report how the LAPB interface
 performs.  These are read-only objects used to monitor operation.
 The lapbXidTable is not required for systems that do not transmit XID
 frames. For systems that do transmit XID frames, this table provides
 the values for the fields of the XID frame that are not already
 present in the lapbAdmnTable.  The objects in this table are read-
 write.

Throop & Baker [Page 5] RFC 1381 X.25 LAPB MIB November 1992

3.5. Traps

 Since all LAPB interfaces have entries in the ifTable, significant
 changes in the state of the interface should send a linkUp or
 linkDown trap. Thus an interface that receives or sends a Frame
 Reject frame should send a linkDown trap.  If the interface later
 comes back up, it should then send a linkUP trap.

4. Object Definitions

        RFC1381-MIB DEFINITIONS ::= BEGIN
        IMPORTS
                Counter
                        FROM RFC1155-SMI
                transmission
                        FROM RFC1213-MIB
                OBJECT-TYPE
                        FROM RFC-1212;
  1. - LAPB MIB
        lapb    OBJECT IDENTIFIER ::= { transmission 16 }
        PositiveInteger ::= INTEGER (0..2147483647)
        IfIndexType     ::= INTEGER (1..2147483647)
        -- IfIndexType specifies an index object for a table
        -- with entries that match entries in the MIB-II ifTable.
        -- The value of the index for the table will match the
        -- ifIndex entry for same interface in the ifTable.
        -- The values of this object range from 1 to ifNumber
        -- inclusive.
  1. - ###########################################################
  2. - LAPB Admn Table
  3. - ###########################################################
  1. - Support of the lapbAdmnTable is mandatory for all
  2. - agents of systems that implement LAPB.
        lapbAdmnTable   OBJECT-TYPE
                SYNTAX  SEQUENCE OF LapbAdmnEntry
                ACCESS  not-accessible
                STATUS  mandatory

Throop & Baker [Page 6] RFC 1381 X.25 LAPB MIB November 1992

                DESCRIPTION
                        "This table contains objects that can be
                        changed to manage a LAPB interface.
                        Changing one of these parameters may take
                        effect in the operating LAPB immediately or
                        may wait until the interface is restarted
                        depending on the details of the
                        implementation.
                        Most of the objects in this read-write table
                        have corresponding read-only objects in the
                        lapbOperTable that return the current
                        operating value.
                        The operating values may be different from
                        these configured values if changed by XID
                        negotiation or if a configured parameter was
                        changed after the interface was started."
                ::= { lapb 1 }
        lapbAdmnEntry   OBJECT-TYPE
                SYNTAX  LapbAdmnEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "Configured parameter values for a specific
                        LAPB."
                INDEX { lapbAdmnIndex }
                ::= { lapbAdmnTable 1 }
        LapbAdmnEntry ::= SEQUENCE {
                lapbAdmnIndex
                        IfIndexType,
                lapbAdmnStationType
                        INTEGER,
                lapbAdmnControlField
                        INTEGER,
                lapbAdmnTransmitN1FrameSize
                        PositiveInteger,
                lapbAdmnReceiveN1FrameSize
                        PositiveInteger,
                lapbAdmnTransmitKWindowSize
                        INTEGER,
                lapbAdmnReceiveKWindowSize
                        INTEGER,
                lapbAdmnN2RxmitCount
                INTEGER,
                lapbAdmnT1AckTimer

Throop & Baker [Page 7] RFC 1381 X.25 LAPB MIB November 1992

                        PositiveInteger,
                lapbAdmnT2AckDelayTimer
                        PositiveInteger,
                lapbAdmnT3DisconnectTimer
                        PositiveInteger,
                lapbAdmnT4IdleTimer
                        PositiveInteger,
                lapbAdmnActionInitiate
                        INTEGER,
                lapbAdmnActionRecvDM
                        INTEGER
                }
        lapbAdmnIndex   OBJECT-TYPE
                SYNTAX  IfIndexType
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The ifIndex value for the LAPB interface."
                ::= { lapbAdmnEntry 1 }
        lapbAdmnStationType     OBJECT-TYPE
                SYNTAX  INTEGER {
                        dte (1),
                        dce (2),
                        dxe (3)
                        }
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "Identifies the desired station type of this
                        interface."
                REFERENCE "ISO 7776 section 3.1"
                DEFVAL { dte }
                ::= { lapbAdmnEntry 2 }
        lapbAdmnControlField OBJECT-TYPE
                SYNTAX  INTEGER {
                        modulo8 (1),
                        modulo128 (2)
                        }
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The desired size of the sequence numbers
                        used to number frames."
                REFERENCE "ISO 8885 Table 3, Name: HDLC Option - 10"
                DEFVAL { modulo8 }

Throop & Baker [Page 8] RFC 1381 X.25 LAPB MIB November 1992

                ::= { lapbAdmnEntry 3 }
        lapbAdmnTransmitN1FrameSize OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default maximum N1 frame size desired
                        in number of bits for a frame transmitted by
                        this DTE.  This excludes flags and 0 bits
                        inserted for transparency."
                REFERENCE "ISO 8885 Table 3,
                        Name: Information Field length"
                DEFVAL { 36000 } -- 4500 * 8; 802.5 Frame size
                ::= { lapbAdmnEntry 4 }
        lapbAdmnReceiveN1FrameSize OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default maximum N1 frame size desired
                        in number of bits for a frame the DCE/remote
                        DTE transmits to this DTE.  This excludes
                        flags and 0 bits inserted for transparency."
                DEFVAL { 36000  } -- 4500 * 8; 802.5 Frame size
                ::= { lapbAdmnEntry 5 }
        lapbAdmnTransmitKWindowSize OBJECT-TYPE
                SYNTAX  INTEGER (1..127)
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default transmit window size for this
                        Interface.  This is the maximum number of
                        unacknowledged sequenced PDUs that may be
                        outstanding from this DTE at any one time."
                REFERENCE "ISO 8885 Table 3, Name: Window size"
                DEFVAL { 7 }
                ::= { lapbAdmnEntry 6 }
        lapbAdmnReceiveKWindowSize OBJECT-TYPE
                SYNTAX  INTEGER (1..127)
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default receive window size for this
                        Interface.  This is the maximum number of

Throop & Baker [Page 9] RFC 1381 X.25 LAPB MIB November 1992

                        unacknowledged sequenced PDUs that may be
                        outstanding from the DCE/remote DTE at any
                        one time."
                REFERENCE "ISO 8885 Table 3, Name: Window size"
                DEFVAL { 7 }
                ::= { lapbAdmnEntry 7 }
        lapbAdmnN2RxmitCount    OBJECT-TYPE
                SYNTAX  INTEGER (0..65535)
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default N2 retry counter for this
                        interface.  This specifies the number of
                        times a PDU will be resent after the T1
                        timer expires without an acknowledgement for
                        the PDU."
                REFERENCE "ISO 8885 Table 3,
                        Name: Retransmission Attempts"
                DEFVAL { 20 }
                ::= { lapbAdmnEntry 8 }
        lapbAdmnT1AckTimer      OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default T1 timer for this interface.
                        This specifies the maximum time in
                        Milliseconds to wait for acknowledgment of a
                        PDU."
                REFERENCE "ISO 8885 Table 3, Name:
                        Acknowledgement timer"
                DEFVAL { 3000 }
                ::= { lapbAdmnEntry 9 }
        lapbAdmnT2AckDelayTimer         OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The default T2 timer for this interface.
                        This specifies the maximum time in
                        Milliseconds to wait before sending an
                        acknowledgment for a sequenced PDU.  A value
                        of zero means there will be no delay in
                        acknowledgement generation."
                REFERENCE "ISO 8885 Table 3,

Throop & Baker [Page 10] RFC 1381 X.25 LAPB MIB November 1992

                        Name: Reply delay timer"
                DEFVAL { 0 }
                ::= { lapbAdmnEntry 10 }
        lapbAdmnT3DisconnectTimer OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The T3 timer for this interface.  This
                        specifies the time in Milliseconds to wait
                        before considering the link disconnected.  A
                        value of zero indicates the link will be
                        considered disconnected upon completion of
                        the frame exchange to disconnect the link."
                REFERENCE "ISO 7776 section 5.7.1.3"
                DEFVAL { 60000 }
                ::= { lapbAdmnEntry 11 }
        lapbAdmnT4IdleTimer OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The T4 timer for this interface.  This
                        specifies the maximum time in Milliseconds
                        to allow without frames being exchanged on
                        the data link.  A value of 2147483647
                        indicates no idle timer is being kept."
                REFERENCE "ISO 7776 section 5.7.1.4"
                DEFVAL { 2147483647 }
                ::= { lapbAdmnEntry 12 }
        lapbAdmnActionInitiate OBJECT-TYPE
                SYNTAX  INTEGER {
                sendSABM (1),
                        sendDISC (2),
                        sendDM (3),
                        none (4),
                        other (5)
                        }
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "This identifies the action LAPB will take
                        to initiate link set-up."
                DEFVAL { sendSABM }
                ::= { lapbAdmnEntry 13 }

Throop & Baker [Page 11] RFC 1381 X.25 LAPB MIB November 1992

        lapbAdmnActionRecvDM OBJECT-TYPE
                SYNTAX  INTEGER {
                        sendSABM (1),
                        sendDISC (2),
                        other (3)
                        }
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "This identifies the action LAPB will take
                        when it receives a DM response."
                DEFVAL { sendSABM }
                ::= { lapbAdmnEntry 14 }
  1. - ###########################################################
  2. - LAPB operating parameters.
  3. - ###########################################################
  1. - Support of the lapbOperTable is mandatory for all
  2. - agents of systems that implement LAPB.
        lapbOperTable   OBJECT-TYPE
                SYNTAX  SEQUENCE OF LapbOperEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "This table contains configuration
                        information about interface parameters
                        currently set in the interface.  Many of
                        these objects have corresponding objects in
                the lapbAdmnTable."
                ::= { lapb 2 }
        lapbOperEntry   OBJECT-TYPE
                SYNTAX  LapbOperEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "Currently set parameter values for a
                        specific LAPB."
                INDEX { lapbOperIndex }
                ::= { lapbOperTable 1 }
        LapbOperEntry ::= SEQUENCE {
                lapbOperIndex
                        IfIndexType,
                lapbOperStationType

Throop & Baker [Page 12] RFC 1381 X.25 LAPB MIB November 1992

                        INTEGER,
                lapbOperControlField
                        INTEGER,
                lapbOperTransmitN1FrameSize
                        PositiveInteger,
                lapbOperReceiveN1FrameSize
                        PositiveInteger,
                lapbOperTransmitKWindowSize
                        INTEGER,
                lapbOperReceiveKWindowSize
                        INTEGER,
                lapbOperN2RxmitCount
                        INTEGER,
                lapbOperT1AckTimer
                        PositiveInteger,
                lapbOperT2AckDelayTimer
                        PositiveInteger,
                lapbOperT3DisconnectTimer
                        PositiveInteger,
                lapbOperT4IdleTimer
                        PositiveInteger,
                lapbOperPortId
                        OBJECT IDENTIFIER,
                lapbOperProtocolVersionId
                        OBJECT IDENTIFIER
                }
        lapbOperIndex   OBJECT-TYPE
           SYNTAX       IfIndexType
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The ifIndex value for the LAPB interface."
                ::= { lapbOperEntry 1 }
        lapbOperStationType     OBJECT-TYPE
                SYNTAX  INTEGER {
                        dte (1),
                        dce (2),
                        dxe (3)
                        }
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "Identifies the current operating station
                        type of this interface.  A value of dxe (3)
                        indicates XID negotiation has not yet taken
                        place."

Throop & Baker [Page 13] RFC 1381 X.25 LAPB MIB November 1992

                REFERENCE "ISO 7776 section 3.1"
                ::= { lapbOperEntry 2 }
        lapbOperControlField OBJECT-TYPE
                SYNTAX  INTEGER {
                        modulo8 (1),
                        modulo128 (2)
                        }
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current operating size of the sequence
                        numbers used to number frames."
                REFERENCE "ISO 7776 section 3.3"
                ::= { lapbOperEntry 3 }
        lapbOperTransmitN1FrameSize OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current operating N1 frame size used
                        for the maximum number of bits in a frame
                        this DTE can transmit.  This excludes flags
                        and 0 bits inserted for transparency."
                REFERENCE "ISO 7776 section 5.7.3"
                ::= { lapbOperEntry 4 }
        lapbOperReceiveN1FrameSize OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-only
                STATUS  mandatory
                -- See lapbOperTransmitN1FrameSize above
                DESCRIPTION
                        "The current operating N1 frame size used
                        for the maximum number of bits in a frame
                        the DCE/remote DTE can transmit.  This
                        excludes flags and 0 bits inserted for
                        transparency."
                ::= { lapbOperEntry 5 }
        lapbOperTransmitKWindowSize OBJECT-TYPE
                SYNTAX  INTEGER (1..127)
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current PDU window size this Interface
                        uses to transmit.  This is the maximum

Throop & Baker [Page 14] RFC 1381 X.25 LAPB MIB November 1992

                        number of unacknowledged sequenced PDUs that
                        may be outstanding from this DTE at any one
                        time."
                REFERENCE "ISO 7776 section 5.7.4"
                ::= { lapbOperEntry 6 }
        lapbOperReceiveKWindowSize OBJECT-TYPE
                SYNTAX  INTEGER (1..127)
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current receive PDU window size for
                        this Interface.  This is the maximum number
                        of unacknowledged sequenced PDUs that may be
                        outstanding from the DCE/remote DTE at any
                        one time."
                REFERENCE "ISO 7776 section 5.7.4"
                ::= { lapbOperEntry 7 }
        lapbOperN2RxmitCount    OBJECT-TYPE
                SYNTAX  INTEGER (0..65535)
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current N2 retry counter used for this
                        interface.  This specifies the number of
                        times a PDU will be resent after the T1
                        timer expires without an acknowledgement for
                        the PDU."
                REFERENCE "ISO 7776 section 5.7.2"
                ::= { lapbOperEntry 8 }
        lapbOperT1AckTimer      OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current T1 timer for this interface.
                        This specifies the maximum time in
                        Milliseconds to wait for acknowledgment of a
                        PDU."
                REFERENCE "ISO 7776 section 5.7.1.1"
                ::= { lapbOperEntry 9 }
        lapbOperT2AckDelayTimer         OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-only
                STATUS  mandatory

Throop & Baker [Page 15] RFC 1381 X.25 LAPB MIB November 1992

                DESCRIPTION
                        "The current T2 timer for this interface.
                        This specifies the maximum time in
                        Milliseconds to wait before sending an
                        acknowledgment for a sequenced PDU.  A value
                        of zero means there will be no delay in
                        acknowledgement generation."
                REFERENCE "ISO 7776 section 5.7.1.2"
                ::= { lapbOperEntry 10 }
        lapbOperT3DisconnectTimer OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current T3 timer for this interface.
                        This specifies the time in Milliseconds to
                        wait before considering the link
                        disconnected.  A value of zero indicates the
                        link will be considered disconnected upon
                        completion of the frame exchange to
                        disconnect the link."
                REFERENCE "ISO 7776 section 5.7.1.3"
                ::= { lapbOperEntry 11 }
        lapbOperT4IdleTimer OBJECT-TYPE
                SYNTAX  PositiveInteger
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The current T4 timer for this interface.
                        This specifies the maximum time in
                        Milliseconds to allow without frames being
                        exchanged on the data link.  A value of
                        2147483647 indicates no idle timer is being
                        kept."
                REFERENCE "ISO 7776 section 5.7.1.4"
                ::= { lapbOperEntry 12 }
        lapbOperPortId OBJECT-TYPE
                SYNTAX  OBJECT IDENTIFIER
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "This object identifies an instance of the
                        index object in the first group of objects
                        in the MIB specific to the physical device
                        or interface used to send and receive

Throop & Baker [Page 16] RFC 1381 X.25 LAPB MIB November 1992

                        frames.  If an agent does not support any
                        such objects, it should return nullSpec
                        OBJECT IDENTIFIER {0 0}."
                ::= { lapbOperEntry 13 }
        lapbOperProtocolVersionId       OBJECT-TYPE
                SYNTAX  OBJECT IDENTIFIER
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "This object identifies the version of the
                        lapb protocol implemented by this
                        interface."
                ::= { lapbOperEntry 14 }
  1. - ###########################################################
  2. - LAPB Flow Table
  3. - ###########################################################
  1. - Support of the lapbFlowTable is mandatory for all
  2. - agents of systems that implement LAPB.
        lapbFlowTable OBJECT-TYPE
                SYNTAX  SEQUENCE OF LapbFlowEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "This table defines the objects recorded by
                        LAPB to provide information about the
                        traffic flow through the interface."
                ::= { lapb 3 }
        lapbFlowEntry OBJECT-TYPE
                SYNTAX  LapbFlowEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "The information regarding the effects of
                        flow controls in LAPB."
                 INDEX { lapbFlowIfIndex }
                ::= { lapbFlowTable 1 }
        LapbFlowEntry ::= SEQUENCE {
                lapbFlowIfIndex
                        IfIndexType,
                lapbFlowStateChanges
                        Counter,

Throop & Baker [Page 17] RFC 1381 X.25 LAPB MIB November 1992

                lapbFlowChangeReason
                        INTEGER,
                lapbFlowCurrentMode
                        INTEGER,
                lapbFlowBusyDefers
                        Counter,
                lapbFlowRejOutPkts
                        Counter,
                lapbFlowRejInPkts
                        Counter,
                lapbFlowT1Timeouts
                        Counter,
                lapbFlowFrmrSent
                OCTET STRING,
                lapbFlowFrmrReceived
                        OCTET STRING,
                lapbFlowXidReceived
                        OCTET STRING
                }
        lapbFlowIfIndex OBJECT-TYPE
                SYNTAX  IfIndexType
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The ifIndex value for the LAPB Interface."
                ::= { lapbFlowEntry 1 }
        lapbFlowStateChanges OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The number of LAPB State Changes, including
                        resets."
                ::= { lapbFlowEntry 2 }
        lapbFlowChangeReason OBJECT-TYPE
                SYNTAX  INTEGER {
                        notStarted (1),    -- Initial state
                        abmEntered (2),    -- SABM or UA
                        abmeEntered (3),   -- SABME or UA
                        abmReset (4),      -- SABM in ABM
                        abmeReset (5),     -- SABME in ABME
                        dmReceived (6),    -- DM Response
                        dmSent (7),        -- DM sent
                        discReceived (8),  -- DISC Response
                        discSent (9),      -- DISC Sent

Throop & Baker [Page 18] RFC 1381 X.25 LAPB MIB November 1992

                        frmrReceived (10), -- FRMR Received
                        frmrSent (11),     -- FRMR Sent
                        n2Timeout (12),    -- N2 Timer Expired
                        other (13)
                          }
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The reason for the most recent incrementing
                        of lapbFlowStateChanges.  A DM or DISC frame
                        generated to initiate link set-up does not
                        alter this object.  When the MIB-II object
                        ifOperStatus does not have a value of
                        testing, there exists a correlation between
                        this object and ifOperStatus.  IfOperStatus
                        will have a value of up when this object
                        contains:  abmEntered, abmeEntered,
                        abmReset, or abmeReset.  IfOperStatus will
                        have a value of down when this object has a
                        value of notStarted, or dmReceived through
                        n2Timeout.  There is no correlation when
                        this object has the value other."
                ::= { lapbFlowEntry 3 }
        lapbFlowCurrentMode OBJECT-TYPE
                SYNTAX  INTEGER {
                        disconnected (1),
                                -- initial state or DISC received
                        linkSetup (2),
                                -- SABM sent
                        frameReject (3),
                                -- Invalid frame received and
                                -- FRMR sent
                        disconnectRequest (4),
                                -- DISC sent
                        informationTransfer (5),
                                -- normal information transfer state
                                -- SABM(E) sent and UA received, or
                                -- SABM(E) received and UA sent
                        rejFrameSent (6),
                                -- invalid NS received and REJ sent
                        waitingAcknowledgement (7),

Throop & Baker [Page 19] RFC 1381 X.25 LAPB MIB November 1992

  1. - T1 expired and RR sent
                        stationBusy (8),
                                -- RNR sent
                        remoteStationBusy (9),
                                -- RNR received
                        bothStationsBusy (10),
                                -- RNR received and RNR sent
                        waitingAckStationBusy (11),
                                -- T1 expired, RNR sent
                        waitingAckRemoteBusy (12),
                                -- T1 expired, RNR received
                        waitingAckBothBusy (13),
                                -- T1 expired, RNR sent,
                                -- and RNR received
                        rejFrameSentRemoteBusy (14),
                                -- REJ sent and RNR received
                        xidFrameSent (15),
                                -- XID frame sent
                        error (16),
                                -- An error state other than
                                -- a one defined above
                        other (17)
                                --  A state not listed above
                          }
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The current condition of the conversation."
                ::= { lapbFlowEntry 4 }
        lapbFlowBusyDefers OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The number of times this device was unable
                        to transmit a frame due to a perceived
                        remote busy condition.  Busy conditions can

Throop & Baker [Page 20] RFC 1381 X.25 LAPB MIB November 1992

                        result from the receipt of an RNR from the
                        remote device, the lack of valid sequence
                        number space (window saturation), or other
                        conditions."
                ::= { lapbFlowEntry 5 }
        lapbFlowRejOutPkts OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The number of REJ or SREJ frames sent by
                        this station."
                ::= { lapbFlowEntry 6 }
        lapbFlowRejInPkts OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The number of REJ or SREJ frames received
                        by this station."
                ::= { lapbFlowEntry 7 }
        lapbFlowT1Timeouts OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The number of times a re-transmission was
                        effected by the T1 Timer expiring."
                ::= { lapbFlowEntry 8 }
        lapbFlowFrmrSent OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..7))
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The Information Field of the FRMR most
                        recently sent.  If no FRMR has been sent
                        (the normal case) or the information isn't
                        available, this will be an OCTET STRING of
                        zero length."
                REFERENCE "ISO 7776 Section 4.3.9, tables 7 and 8"
                ::= { lapbFlowEntry 9 }
        lapbFlowFrmrReceived OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..7))

Throop & Baker [Page 21] RFC 1381 X.25 LAPB MIB November 1992

                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The Information Field of the FRMR most
                        recently received.  If no FRMR has been
                        received (the normal case) or the
                        information isn't available, this will be an
                        OCTET STRING of zero length."
                REFERENCE "ISO 7776 Section 4.3.9, tables 7 and 8"
                ::= { lapbFlowEntry 10 }
        lapbFlowXidReceived OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..8206))
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The Information Field of the XID frame most
                        recently received.  If no XID frame has been
                        received, this will be an OCTET STRING of
                        zero length."
                REFERENCE "ISO 8885"
                ::= { lapbFlowEntry 11 }
  1. - ###########################################################
  2. - LAPB XID Table
  3. - ###########################################################
  1. - Support for the lapbXidTable is mandatory for all agents
  2. - of systems that have a LAPB implementation using XID
  3. - negotiation. Agents of systems without XID negotiation
  4. - support should not implement this table.
        lapbXidTable    OBJECT-TYPE
                SYNTAX  SEQUENCE OF LapbXidEntry
                ACCESS  not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "This table defines values to use for XID
                        negotiation that are not found in the
                        lapbAdmnTable.  This table is optional for
                        implementations that don't support XID and
                        mandatory for implementations that do
                        initiate XID negotiation."
                ::= { lapb 4 }
        lapbXidEntry    OBJECT-TYPE
                SYNTAX  LapbXidEntry

Throop & Baker [Page 22] RFC 1381 X.25 LAPB MIB November 1992

           ACCESS       not-accessible
                STATUS  mandatory
                DESCRIPTION
                        "XId negotiation parameter values for a
                        specific LAPB."
                INDEX { lapbXidIndex }
                ::= { lapbXidTable 1 }
        LapbXidEntry ::= SEQUENCE {
                lapbXidIndex
                        IfIndexType,
                lapbXidAdRIdentifier
                        OCTET STRING,
                lapbXidAdRAddress
                        OCTET STRING,
                lapbXidParameterUniqueIdentifier
                        OCTET STRING,
                lapbXidGroupAddress
                        OCTET STRING,
                lapbXidPortNumber
                        OCTET STRING,
                lapbXidUserDataSubfield
                        OCTET STRING
                }
        lapbXidIndex    OBJECT-TYPE
                SYNTAX  IfIndexType
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The ifIndex value for the LAPB interface."
                ::= { lapbXidEntry 1 }
        lapbXidAdRIdentifier OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..255))
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The value of the Address Resolution
                        Identifier.  A zero length string indicates
                        no Identifier value has been assigned."
                REFERENCE "ISO 8885 Table 2, Name: Identifier"
                DEFVAL { ''h }
                ::= { lapbXidEntry 2 }
        lapbXidAdRAddress OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..255))

Throop & Baker [Page 23] RFC 1381 X.25 LAPB MIB November 1992

                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The value of the Address Resolution
                        Address.  A zero length string indicates no
                        Address value has been assigned."
                REFERENCE "ISO 8885 Table 2, Name: Address"
                DEFVAL { ''h }
                ::= { lapbXidEntry 3 }
        lapbXidParameterUniqueIdentifier OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..255))
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The value of the parameter unique
                        Identifier.  A zero length string indicates
                        no Unique identifier value has been
                        assigned."
                REFERENCE "ISO 8885 Table 3, Name: Identifier"
                DEFVAL { ''h }
                ::= { lapbXidEntry 4 }
        lapbXidGroupAddress OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..255))
                ACCESS  read-write
                STATUS  mandatory
                DESCRIPTION
                        "The value of the parameter Group address.
                        A zero length string indicates no Group
                        address value has been assigned."
                REFERENCE "ISO 8885 Table 3, Name: Group address"
                DEFVAL { ''h }
                ::= { lapbXidEntry 5 }
        lapbXidPortNumber OBJECT-TYPE
                SYNTAX  OCTET STRING (SIZE (0..255))
                ACCESS  read-write
                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

Throop & Baker [Page 24] RFC 1381 X.25 LAPB MIB November 1992

                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 }
  1. - ###########################################################
  2. - LAPB protocol versions
  3. - ###########################################################
        lapbProtocolVersion OBJECT IDENTIFIER
                ::= { lapb 5 }
        lapbProtocolIso7776v1986 OBJECT IDENTIFIER
                ::= { lapbProtocolVersion 1 }
        lapbProtocolCcittV1980 OBJECT IDENTIFIER
                ::= { lapbProtocolVersion 2 }
        lapbProtocolCcittV1984 OBJECT IDENTIFIER
                ::= { lapbProtocolVersion 3 }
  1. - The following describes some of the MIB-II interface
  2. - objects and their relationship with the objects in this
  3. - MIB extension.
  1. - ifDescr: describes the interface. It should include
  2. - identification information for the physical line and a
  3. - description of the network. For connections to PDNs,
  4. - it should name the PDN.
  1. - ifMtu: the maximum number of octets an upper layer can
  2. - pass to this interface as a single frame.
  1. - ifSpeed:

Throop & Baker [Page 25] RFC 1381 X.25 LAPB MIB November 1992

  1. - ifAdminStatus:
  1. - ifOperStatus:
  1. - ifLastChange: the last time the state of the interface
  2. - changed. A reset is considered an instantaneous change to
  3. - the ndm state and back to abm or abme. This will be the
  4. - last time that lapbFlowChangeReason and lapbFlowChanges
  5. - changed.
  1. - ifInOctets: contains the number of octets
  2. - received from the peer LAPB including FCS.
  1. - ifInUcastPkts: contains the number of I-frames delivered
  2. - by this interface to a higher layer interface.
  1. - ifInDiscards: contains the number of received
  2. - frames discarded because of internal conditions
  3. - (such as lack of buffering).
  1. - ifInErrors: contains the number of Invalid frames received.
  2. - This does not have any relationship with the number REJ,
  3. - or RNR frames sent or received.
  1. - ifInUnknownProtos: contains the number of frames
  2. - that were correct but were dropped because they
  3. - were inappropriate for the current state. This
  4. - includes an invalid Poll bit, an unknown address,
  5. - or other condition such as an RNR when connection
  6. - not established. This also includes the number of
  7. - DISC or other frames that were ignored because the
  8. - link was not established and this interface was not
  9. - configured to perform link setup on that type frame.
  1. - ifOutOctets: number of octets sent to peer including
  2. - FCS octets.
  1. - ifOutUcastPkts: number of I-frames received from
  2. - a higher layer for transmission to peer.
  1. - ifOutDiscards: number of frames to be sent that were
  2. - dropped due to internal conditions such as buffering etc.
  1. - ifOutErrors: number of transmissions that failed
  2. - due to errors or were considered invalid by the receiver.
  3. - This does not have any relationship with the number REJ,
  4. - or RNR frames sent or received.

Throop & Baker [Page 26] RFC 1381 X.25 LAPB MIB November 1992

  1. - ifOutQLen: number of frames waiting to be transmitted.
  1. - This MIB does not provide any support for:
  2. - Multilink procedure (MLP) in ISO 7776 section 6
  3. - LLC Pbit timer
  4. - LLC REJ timer
  5. - LLC Busy State Timer 7.8.1.4
  1. - ###########################################################
        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.

Throop & Baker [Page 27] RFC 1381 X.25 LAPB MIB November 1992

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

Throop & Baker [Page 28] RFC 1381 X.25 LAPB MIB November 1992

    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.

Throop & Baker [Page 29] RFC 1381 X.25 LAPB MIB November 1992

    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
                Gary Bjerke, Tandem
                Bill Bowman, HP
                Christopher Bucci, Datability
                Charles Carvalho, ACC
                Jeff Case, Snmp Research
                Angela Chen, HP
                Carson Cheung, BNR
                Tom Daniel, Spider Systems
                Chuck Davin, MIT
                Billy Durham, Honeywell
                Richard Fox, Synoptics
                Doug Geller, Data General
                Herve Goguely, LIR Corp
                Andy Goldthorpe, british-telecom
                Walter D. Guilarte
                David Gurevich
                Steve Huston, Process Software Corporation

Throop & Baker [Page 30] RFC 1381 X.25 LAPB MIB November 1992

                Jon Infante, ICL
                Frank Kastenholz, Clearpoint
                Zbigniew Kielczewski, Eicon
                Cheryl Krupezak, Georgia Tech
                Mats Lindstrom, Diab Data AB
                Andrew Malis, BBN
                Evan McGinnis, 3Com
                Gary (G.P.)Mussar, BNR
                Chandy Nilakantan, 3Com
                Randy Pafford, Data General
                Ragnar Paulson, The Software Group Limited
                Dave Perkins, Synoptics
                Walter Pinkarschewsky, DEC
                Karen Quidley, Data General
                Chris Ranch, Novell
                Paul S. Rarey, DHL Systems Inc.
                Jim Roche, Newbridge Research
                Philippe Roger, LIR Corp.
                Timon Sloane
                Mike Shand, DEC
                Brad Steina, Microcom
                Bob Stewart, Xyplex
                Tom Sullivan, Data General
                Rodney Thayer, Sable Technology Corporation
                Mark Therieau, Microcom
                Jane Thorn, Data General
                Dean Throop, Data General
                Maurice Turcotte, Racal Datacom
                Mike Zendels, Data General
 In addition, the comments of the following individuals are also
 acknowledged:
                Keith McCloghrie

7. References

 [1] Rose M., and K. McCloghrie, "Structure and Identification of
     Management Information for TCP/IP-based internets", STD 16, RFC
     1155, Performance Systems International, Hughes LAN Systems, May
     1990.
 [2] McCloghrie K., and M. Rose, "Management Information Base for
     Network Management of TCP/IP-based internets", RFC 1156, Hughes
     LAN Systems, Performance Systems International, May 1990.
 [3] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple

Throop & Baker [Page 31] RFC 1381 X.25 LAPB MIB November 1992

     Network Management Protocol", STD 15, RFC 1157, SNMP Research,
     Performance Systems International, Performance Systems
     International, MIT Laboratory for Computer Science, May 1990.
 [4] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
     STD 16, RFC 1212, Performance Systems International, Hughes LAN
     Systems, March 1991.
 [5] Rose M., Editor, "Management Information Base for Network
     Management of TCP/IP-based internets: MIB-II", STD 17, RFC 1213,
     Performance Systems International, March 1991.
 [6] Information processing systems - Open Systems Interconnection -
     Specification of Abstract Syntax Notation One (ASN.1),
     International Organization for Standardization, International
     Standard 8824, December 1987.
 [7] Information processing systems - Open Systems Interconnection -
     Specification of Basic Encoding Rules for Abstract Notation One
     (ASN.1), International Organization for Standardization,
     International Standard 8825, December 1987.
 [8] Stewart, B., Editor, "Definitions of Managed Objects for RS-232-
     like Hardware Devices", RFC 1317, Xyplex, Inc., April 1992.
 [9] Throop, D., Editor, "SNMP MIB extension for the Packet Layer of
     X.25", RFC 1382, Data General Corporation, November 1992.
[10] "Information processing systems - Data communication - High-level
     data link control procedure - Description of the X.25 LAPB-
     compatible DTE data link procedures", International Organization
     for Standardization, International Standard 7776, December 1986.
[11] "Information technology - Telecommunications and information
     exchange between systems - High-level data link control (HDLC)
     procedures - General purpose XID frame information field contents
     and format", International Organization for Standardization,
     International Standard 8885.

Throop & Baker [Page 32] RFC 1381 X.25 LAPB MIB November 1992

8. Security Considerations

 Security issues are not discussed in this memo.

9. Authors' Addresses

 Dean D. Throop
 Data General Corporation
 62 Alexander Dr.
 Research Triangle Park, NC 27709
 Phone: (919)248-8421
 EMail: throop@dg-rtp.dg.com
 Fred Baker
 Advanced Computer Communications
 315 Bollay Drive
 Santa Barbara, CA 93101
 Phone: (805) 685-4455
 EMail: fbaker@acc.com
 While the working group has completed discussion of this document,
 comments are still welcome.  Please send comments to the x25mib
 working group at: x25mib@dg-rtp.dg.com

Throop & Baker [Page 33]

/data/webs/external/dokuwiki/data/pages/rfc/rfc1381.txt · Last modified: 1992/11/09 18:29 (external edit)