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RFC 2233

 
 
 

The Interfaces Group MIB using SMIv2

Part 3 of 3, p. 48 to 66
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   ifStackHigherLayer  OBJECT-TYPE
        SYNTAX        Integer32
        MAX-ACCESS    not-accessible
        STATUS        current
        DESCRIPTION
               "The value of ifIndex corresponding to the higher
               sub-layer of the relationship, i.e., the sub-layer
               which runs on 'top' of the sub-layer identified by the
               corresponding instance of ifStackLowerLayer.  If there
               is no higher sub-layer (below the internetwork layer),
               then this object has the value 0."
        ::= { ifStackEntry 1 }


   ifStackLowerLayer  OBJECT-TYPE
        SYNTAX        Integer32
        MAX-ACCESS    not-accessible
        STATUS        current
        DESCRIPTION
               "The value of ifIndex corresponding to the lower sub-
               layer of the relationship, i.e., the sub-layer which
               runs 'below' the sub-layer identified by the
               corresponding instance of ifStackHigherLayer.  If
               there is no lower sub-layer, then this object has the
               value 0."
        ::= { ifStackEntry 2 }


   ifStackStatus  OBJECT-TYPE
       SYNTAX         RowStatus
       MAX-ACCESS     read-create
       STATUS         current
       DESCRIPTION
               "The status of the relationship between two sub-
               layers.

               Changing the value of this object from 'active' to
               'notInService' or 'destroy' will likely have
               consequences up and down the interface stack.  Thus,
               write access to this object is likely to be
               inappropriate for some types of interfaces, and many
               implementations will choose not to support write-
               access for any type of interface."
       ::= { ifStackEntry 3 }

   ifStackLastChange OBJECT-TYPE
       SYNTAX         TimeTicks
       MAX-ACCESS     read-only

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       STATUS         current
       DESCRIPTION
               "The value of sysUpTime at the time of the last change
               of the (whole) interface stack.  A change of the
               interface stack is defined to be any creation,
               deletion, or change in value of any instance of
               ifStackStatus.  If the interface stack has been
               unchanged since the last re-initialization of the
               local network management subsystem, then this object
               contains a zero value."
       ::= { ifMIBObjects 6 }


   --   Generic Receive Address Table
   --
   -- This group of objects is mandatory for all types of
   -- interfaces which can receive packets/frames addressed to
   -- more than one address.
   --
   -- This table replaces the ifExtnsRcvAddr table.  The main
   -- difference is that this table makes use of the RowStatus
   -- textual convention, while ifExtnsRcvAddr did not.

   ifRcvAddressTable  OBJECT-TYPE
       SYNTAX      SEQUENCE OF IfRcvAddressEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "This table contains an entry for each address
               (broadcast, multicast, or uni-cast) for which the
               system will receive packets/frames on a particular
               interface, except as follows:

               - for an interface operating in promiscuous mode,
               entries are only required for those addresses for
               which the system would receive frames were it not
               operating in promiscuous mode.

               - for 802.5 functional addresses, only one entry is
               required, for the address which has the functional
               address bit ANDed with the bit mask of all functional
               addresses for which the interface will accept frames.

               A system is normally able to use any unicast address
               which corresponds to an entry in this table as a
               source address."
       ::= { ifMIBObjects 4 }

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   ifRcvAddressEntry  OBJECT-TYPE
       SYNTAX      IfRcvAddressEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "A list of objects identifying an address for which
               the system will accept packets/frames on the
               particular interface identified by the index value
               ifIndex."
       INDEX  { ifIndex, ifRcvAddressAddress }
       ::= { ifRcvAddressTable 1 }

   IfRcvAddressEntry ::=
       SEQUENCE {
           ifRcvAddressAddress   PhysAddress,
           ifRcvAddressStatus    RowStatus,
           ifRcvAddressType      INTEGER
       }

   ifRcvAddressAddress OBJECT-TYPE
       SYNTAX      PhysAddress
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "An address for which the system will accept
               packets/frames on this entry's interface."

       ::= { ifRcvAddressEntry 1 }

   ifRcvAddressStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
               "This object is used to create and delete rows in the
               ifRcvAddressTable."

       ::= { ifRcvAddressEntry 2 }

   ifRcvAddressType OBJECT-TYPE
       SYNTAX      INTEGER {
                       other(1),
                       volatile(2),
                       nonVolatile(3)
                   }

       MAX-ACCESS  read-create
       STATUS      current

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       DESCRIPTION
               "This object has the value nonVolatile(3) for those
               entries in the table which are valid and will not be
               deleted by the next restart of the managed system.
               Entries having the value volatile(2) are valid and
               exist, but have not been saved, so that will not exist
               after the next restart of the managed system.  Entries
               having the value other(1) are valid and exist but are
               not classified as to whether they will continue to
               exist after the next restart."

       DEFVAL  { volatile }
       ::= { ifRcvAddressEntry 3 }

   -- definition of interface-related traps.

   linkDown NOTIFICATION-TYPE
           OBJECTS { ifIndex, ifAdminStatus, ifOperStatus }
           STATUS  current
           DESCRIPTION
               "A linkDown trap signifies that the SNMPv2 entity,
               acting in an agent role, has detected that the
               ifOperStatus object for one of its communication links
               is about to enter the down state from some other state
               (but not from the notPresent state).  This other state
               is indicated by the included value of ifOperStatus."
       ::= { snmpTraps 3 }

   linkUp NOTIFICATION-TYPE
           OBJECTS { ifIndex, ifAdminStatus, ifOperStatus }
           STATUS  current
           DESCRIPTION
               "A linkDown trap signifies that the SNMPv2 entity,
               acting in an agent role, has detected that the
               ifOperStatus object for one of its communication links
               left the down state and transitioned into some other
               state (but not into the notPresent state).  This other
               state is indicated by the included value of
               ifOperStatus."
       ::= { snmpTraps 4 }

   -- conformance information

   ifConformance OBJECT IDENTIFIER ::= { ifMIB 2 }

   ifGroups      OBJECT IDENTIFIER ::= { ifConformance 1 }
   ifCompliances OBJECT IDENTIFIER ::= { ifConformance 2 }

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   -- compliance statements

   ifCompliance2 MODULE-COMPLIANCE
       STATUS  current
       DESCRIPTION
               "The compliance statement for SNMPv2 entities which
               have network interfaces."

       MODULE  -- this module
           MANDATORY-GROUPS { ifGeneralInformationGroup, ifStackGroup2,
                              ifCounterDiscontinuityGroup }

           GROUP       ifFixedLengthGroup
           DESCRIPTION
               "This group is mandatory for all network interfaces
               which are character-oriented or transmit data in
               fixed-length transmission units."

           GROUP       ifHCFixedLengthGroup
           DESCRIPTION
               "This group is mandatory only for those network
               interfaces which are character-oriented or transmit
               data in fixed-length transmission units, and for which
               the value of the corresponding instance of ifSpeed is
               greater than 20,000,000 bits/second."

           GROUP       ifPacketGroup
           DESCRIPTION
               "This group is mandatory for all network interfaces
               which are packet-oriented."

           GROUP       ifHCPacketGroup
           DESCRIPTION
               "This group is mandatory only for those network
               interfaces which are packet-oriented and for which the
               value of the corresponding instance of ifSpeed is
               greater than 650,000,000 bits/second."

           GROUP       ifRcvAddressGroup
           DESCRIPTION
               "The applicability of this group MUST be defined by
               the media-specific MIBs.  Media-specific MIBs must
               define the exact meaning, use, and semantics of the
               addresses in this group."

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           OBJECT      ifLinkUpDownTrapEnable
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required."

           OBJECT      ifPromiscuousMode
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required."

           OBJECT      ifStackStatus
           SYNTAX      INTEGER { active(1) } -- subset of RowStatus
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required, and only one of the six
               enumerated values for the RowStatus textual convention
               need be supported, specifically: active(1)."

           OBJECT       ifAdminStatus
           SYNTAX       INTEGER { up(1), down(2) }
           MIN-ACCESS   read-only
           DESCRIPTION
               "Write access is not required, nor is support for the
               value testing(3)."

           OBJECT       ifAlias
           MIN-ACCESS   read-only
           DESCRIPTION
               "Write access is not required."

       ::= { ifCompliances 2 }

   -- units of conformance

   ifGeneralInformationGroup    OBJECT-GROUP
       OBJECTS { ifIndex, ifDescr, ifType, ifSpeed, ifPhysAddress,
                 ifAdminStatus, ifOperStatus, ifLastChange,
                 ifLinkUpDownTrapEnable, ifConnectorPresent,
                 ifHighSpeed, ifName, ifNumber, ifAlias,
                 ifTableLastChange }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               applicable to all network interfaces."
       ::= { ifGroups 10 }

   -- the following five groups are mutually exclusive; at most
   -- one of these groups is implemented for any interface

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   ifFixedLengthGroup    OBJECT-GROUP
       OBJECTS { ifInOctets, ifOutOctets, ifInUnknownProtos,
                 ifInErrors, ifOutErrors }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               specific to non-high speed (non-high speed interfaces
               transmit and receive at speeds less than or equal to
               20,000,000 bits/second) character-oriented or fixed-
               length-transmission network interfaces."
       ::= { ifGroups 2 }

   ifHCFixedLengthGroup    OBJECT-GROUP
       OBJECTS { ifHCInOctets, ifHCOutOctets,
                 ifInOctets, ifOutOctets, ifInUnknownProtos,
                 ifInErrors, ifOutErrors }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               specific to high speed (greater than 20,000,000
               bits/second) character-oriented or fixed-length-
               transmission network interfaces."
       ::= { ifGroups 3 }

   ifPacketGroup    OBJECT-GROUP
       OBJECTS { ifInOctets, ifOutOctets, ifInUnknownProtos,
                 ifInErrors, ifOutErrors,
                 ifMtu, ifInUcastPkts, ifInMulticastPkts,
                 ifInBroadcastPkts, ifInDiscards,
                 ifOutUcastPkts, ifOutMulticastPkts,
                 ifOutBroadcastPkts, ifOutDiscards,
                 ifPromiscuousMode }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               specific to non-high speed (non-high speed interfaces
               transmit and receive at speeds less than or equal to
               20,000,000 bits/second) packet-oriented network
               interfaces."
       ::= { ifGroups 4 }

   ifHCPacketGroup    OBJECT-GROUP
       OBJECTS { ifHCInOctets, ifHCOutOctets,
                 ifInOctets, ifOutOctets, ifInUnknownProtos,
                 ifInErrors, ifOutErrors,
                 ifMtu, ifInUcastPkts, ifInMulticastPkts,
                 ifInBroadcastPkts, ifInDiscards,
                 ifOutUcastPkts, ifOutMulticastPkts,

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                 ifOutBroadcastPkts, ifOutDiscards,
                 ifPromiscuousMode }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               specific to high speed (greater than 20,000,000
               bits/second but less than or equal to 650,000,000
               bits/second) packet-oriented network interfaces."
       ::= { ifGroups 5 }

   ifVHCPacketGroup    OBJECT-GROUP
       OBJECTS { ifHCInUcastPkts, ifHCInMulticastPkts,
                 ifHCInBroadcastPkts, ifHCOutUcastPkts,
                 ifHCOutMulticastPkts, ifHCOutBroadcastPkts,
                 ifHCInOctets, ifHCOutOctets,
                 ifInOctets, ifOutOctets, ifInUnknownProtos,
                 ifInErrors, ifOutErrors,
                 ifMtu, ifInUcastPkts, ifInMulticastPkts,
                 ifInBroadcastPkts, ifInDiscards,
                 ifOutUcastPkts, ifOutMulticastPkts,
                 ifOutBroadcastPkts, ifOutDiscards,
                 ifPromiscuousMode }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
               specific to higher speed (greater than 650,000,000
               bits/second) packet-oriented network interfaces."
       ::= { ifGroups 6 }

   ifRcvAddressGroup    OBJECT-GROUP
       OBJECTS { ifRcvAddressStatus, ifRcvAddressType }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information on the
               multiple addresses which an interface receives."
       ::= { ifGroups 7 }

   ifStackGroup2    OBJECT-GROUP
       OBJECTS { ifStackStatus, ifStackLastChange }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information on the
               layering of MIB-II interfaces."
       ::= { ifGroups 11 }

   ifCounterDiscontinuityGroup  OBJECT-GROUP
       OBJECTS { ifCounterDiscontinuityTime }
       STATUS  current

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       DESCRIPTION
               "A collection of objects providing information
               specific to interface counter discontinuities."
       ::= { ifGroups 13 }

   -- Deprecated Definitions - Objects


   --
   --    The Interface Test Table
   --
   -- This group of objects is optional.  However, a media-specific
   -- MIB may make implementation of this group mandatory.
   --
   -- This table replaces the ifExtnsTestTable
   --

   ifTestTable   OBJECT-TYPE
       SYNTAX      SEQUENCE OF IfTestEntry
       MAX-ACCESS  not-accessible
       STATUS      deprecated
       DESCRIPTION
               "This table contains one entry per interface.  It
               defines objects which allow a network manager to
               instruct an agent to test an interface for various
               faults.  Tests for an interface are defined in the
               media-specific MIB for that interface.  After invoking
               a test, the object ifTestResult can be read to
               determine the outcome.  If an agent can not perform
               the test, ifTestResult is set to so indicate.  The
               object ifTestCode can be used to provide further
               test-specific or interface-specific (or even
               enterprise-specific) information concerning the
               outcome of the test.  Only one test can be in progress
               on each interface at any one time.  If one test is in
               progress when another test is invoked, the second test
               is rejected.  Some agents may reject a test when a
               prior test is active on another interface.

               Before starting a test, a manager-station must first
               obtain 'ownership' of the entry in the ifTestTable for
               the interface to be tested.  This is accomplished with
               the ifTestId and ifTestStatus objects as follows:

            try_again:
                get (ifTestId, ifTestStatus)
                while (ifTestStatus != notInUse)
                    /*

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                     * Loop while a test is running or some other
                     * manager is configuring a test.
                     */
                    short delay
                    get (ifTestId, ifTestStatus)
                }

                /*
                 * Is not being used right now -- let's compete
                 * to see who gets it.
                 */
                lock_value = ifTestId

                if ( set(ifTestId = lock_value, ifTestStatus = inUse,
                         ifTestOwner = 'my-IP-address') == FAILURE)
                    /*
                     * Another manager got the ifTestEntry -- go
                     * try again
                     */
                    goto try_again;

                /*
                 * I have the lock
                 */
                set up any test parameters.

                /*
                 * This starts the test
                 */
                set(ifTestType = test_to_run);

                wait for test completion by polling ifTestResult

                when test completes, agent sets ifTestResult
                     agent also sets ifTestStatus = 'notInUse'

                retrieve any additional test results, and ifTestId

                if (ifTestId == lock_value+1) results are valid

              A manager station first retrieves the value of the
              appropriate ifTestId and ifTestStatus objects,
              periodically repeating the retrieval if necessary,
              until the value of ifTestStatus is 'notInUse'.  The
              manager station then tries to set the same ifTestId
              object to the value it just retrieved, the same
              ifTestStatus object to 'inUse', and the corresponding
              ifTestOwner object to a value indicating itself.  If

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              the set operation succeeds then the manager has
              obtained ownership of the ifTestEntry, and the value of
              the ifTestId object is incremented by the agent (per
              the semantics of TestAndIncr).  Failure of the set
              operation indicates that some other manager has
              obtained ownership of the ifTestEntry.

              Once ownership is obtained, any test parameters can be
              setup, and then the test is initiated by setting
              ifTestType.  On completion of the test, the agent sets
              ifTestStatus to 'notInUse'.  Once this occurs, the
              manager can retrieve the results.  In the (rare) event
              that the invocation of tests by two network managers
              were to overlap, then there would be a possibility that
              the first test's results might be overwritten by the
              second test's results prior to the first results being
              read.  This unlikely circumstance can be detected by a
              network manager retrieving ifTestId at the same time as
              retrieving the test results, and ensuring that the
              results are for the desired request.

              If ifTestType is not set within an abnormally long
              period of time after ownership is obtained, the agent
              should time-out the manager, and reset the value of the
              ifTestStatus object back to 'notInUse'.  It is
              suggested that this time-out period be 5 minutes.

              In general, a management station must not retransmit a
              request to invoke a test for which it does not receive
              a response; instead, it properly inspects an agent's
              MIB to determine if the invocation was successful.
              Only if the invocation was unsuccessful, is the
              invocation request retransmitted.

              Some tests may require the interface to be taken off-
              line in order to execute them, or may even require the
              agent to reboot after completion of the test.  In these
              circumstances, communication with the management
              station invoking the test may be lost until after
              completion of the test.  An agent is not required to
              support such tests.  However, if such tests are
              supported, then the agent should make every effort to
              transmit a response to the request which invoked the
              test prior to losing communication.  When the agent is
              restored to normal service, the results of the test are
              properly made available in the appropriate objects.
              Note that this requires that the ifIndex value assigned
              to an interface must be unchanged even if the test

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              causes a reboot.  An agent must reject any test for
              which it cannot, perhaps due to resource constraints,
              make available at least the minimum amount of
              information after that test completes."
       ::= { ifMIBObjects 3 }

   ifTestEntry OBJECT-TYPE
       SYNTAX       IfTestEntry
       MAX-ACCESS   not-accessible
       STATUS       deprecated
       DESCRIPTION
               "An entry containing objects for invoking tests on an
               interface."
       AUGMENTS  { ifEntry }
       ::= { ifTestTable 1 }

   IfTestEntry ::=
       SEQUENCE {
           ifTestId           TestAndIncr,
           ifTestStatus       INTEGER,
           ifTestType         AutonomousType,
           ifTestResult       INTEGER,
           ifTestCode         OBJECT IDENTIFIER,
           ifTestOwner        OwnerString
       }

   ifTestId         OBJECT-TYPE
       SYNTAX       TestAndIncr
       MAX-ACCESS   read-write
       STATUS       deprecated
       DESCRIPTION
               "This object identifies the current invocation of the
               interface's test."
       ::= { ifTestEntry 1 }

   ifTestStatus     OBJECT-TYPE
       SYNTAX       INTEGER { notInUse(1), inUse(2) }
       MAX-ACCESS   read-write
       STATUS       deprecated
       DESCRIPTION
               "This object indicates whether or not some manager
               currently has the necessary 'ownership' required to
               invoke a test on this interface.  A write to this
               object is only successful when it changes its value
               from 'notInUse(1)' to 'inUse(2)'.  After completion of
               a test, the agent resets the value back to
               'notInUse(1)'."
       ::= { ifTestEntry 2 }

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   ifTestType       OBJECT-TYPE
       SYNTAX       AutonomousType
       MAX-ACCESS   read-write
       STATUS       deprecated
       DESCRIPTION
               "A control variable used to start and stop operator-
               initiated interface tests.  Most OBJECT IDENTIFIER
               values assigned to tests are defined elsewhere, in
               association with specific types of interface.
               However, this document assigns a value for a full-
               duplex loopback test, and defines the special meanings
               of the subject identifier:

                   noTest  OBJECT IDENTIFIER ::= { 0 0 }

               When the value noTest is written to this object, no
               action is taken unless a test is in progress, in which
               case the test is aborted.  Writing any other value to
               this object is only valid when no test is currently in
               progress, in which case the indicated test is
               initiated.

               When read, this object always returns the most recent
               value that ifTestType was set to.  If it has not been
               set since the last initialization of the network
               management subsystem on the agent, a value of noTest
               is returned."
       ::= { ifTestEntry 3 }

   ifTestResult  OBJECT-TYPE
       SYNTAX       INTEGER {
                        none(1),          -- no test yet requested
                        success(2),
                        inProgress(3),
                        notSupported(4),
                        unAbleToRun(5),   -- due to state of system
                        aborted(6),
                        failed(7)
                    }
       MAX-ACCESS   read-only
       STATUS       deprecated
       DESCRIPTION
               "This object contains the result of the most recently
               requested test, or the value none(1) if no tests have
               been requested since the last reset.  Note that this
               facility provides no provision for saving the results
               of one test when starting another, as could be
               required if used by multiple managers concurrently."

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       ::= { ifTestEntry 4 }

   ifTestCode  OBJECT-TYPE
       SYNTAX       OBJECT IDENTIFIER
       MAX-ACCESS   read-only
       STATUS       deprecated
       DESCRIPTION
               "This object contains a code which contains more
               specific information on the test result, for example
               an error-code after a failed test.  Error codes and
               other values this object may take are specific to the
               type of interface and/or test.  The value may have the
               semantics of either the AutonomousType or
               InstancePointer textual conventions as defined in RFC
               1903.  The identifier:

                   testCodeUnknown  OBJECT IDENTIFIER ::= { 0 0 }

               is defined for use if no additional result code is
               available."
       ::= { ifTestEntry 5 }

   ifTestOwner      OBJECT-TYPE
       SYNTAX       OwnerString
       MAX-ACCESS   read-write
       STATUS       deprecated
       DESCRIPTION
               "The entity which currently has the 'ownership'
               required to invoke a test on this interface."
       ::= { ifTestEntry 6 }

   -- Deprecated Definitions - Groups


   ifGeneralGroup    OBJECT-GROUP
       OBJECTS { ifDescr, ifType, ifSpeed, ifPhysAddress,
                 ifAdminStatus, ifOperStatus, ifLastChange,
                 ifLinkUpDownTrapEnable, ifConnectorPresent,
                 ifHighSpeed, ifName }
       STATUS  deprecated
       DESCRIPTION
               "A collection of objects deprecated in favour of
               ifGeneralInformationGroup."
       ::= { ifGroups 1 }


   ifTestGroup    OBJECT-GROUP
       OBJECTS { ifTestId, ifTestStatus, ifTestType,

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                 ifTestResult, ifTestCode, ifTestOwner }
       STATUS  deprecated
       DESCRIPTION
               "A collection of objects providing the ability to
               invoke tests on an interface."
       ::= { ifGroups 8 }


   ifStackGroup    OBJECT-GROUP
       OBJECTS { ifStackStatus }
       STATUS  deprecated
       DESCRIPTION
               "The previous collection of objects providing
               information on the layering of MIB-II interfaces."
       ::= { ifGroups 9 }


   ifOldObjectsGroup    OBJECT-GROUP
       OBJECTS { ifInNUcastPkts, ifOutNUcastPkts,
                 ifOutQLen, ifSpecific }
       STATUS  deprecated
       DESCRIPTION
               "The collection of objects deprecated from the
               original MIB-II interfaces group."
       ::= { ifGroups 12 }


   -- Deprecated Definitions - Compliance

   ifCompliance MODULE-COMPLIANCE
       STATUS  deprecated
       DESCRIPTION
               "The previous compliance statement for SNMPv2 entities
               which have network interfaces."

       MODULE  -- this module
           MANDATORY-GROUPS { ifGeneralGroup, ifStackGroup }

           GROUP       ifFixedLengthGroup
           DESCRIPTION
               "This group is mandatory for all network interfaces
               which are character-oriented or transmit data in
               fixed-length transmission units."

           GROUP       ifHCFixedLengthGroup
           DESCRIPTION
               "This group is mandatory only for those network
               interfaces which are character-oriented or transmit

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               data in fixed-length transmission units, and for which
               the value of the corresponding instance of ifSpeed is
               greater than 20,000,000 bits/second."

           GROUP       ifPacketGroup
           DESCRIPTION
               "This group is mandatory for all network interfaces
               which are packet-oriented."

           GROUP       ifHCPacketGroup
           DESCRIPTION
               "This group is mandatory only for those network
               interfaces which are packet-oriented and for which the
               value of the corresponding instance of ifSpeed is
               greater than 650,000,000 bits/second."

           GROUP       ifTestGroup
           DESCRIPTION
               "This group is optional.  Media-specific MIBs which
               require interface tests are strongly encouraged to use
               this group for invoking tests and reporting results.
               A medium specific MIB which has mandatory tests may
               make implementation of this group mandatory."

           GROUP       ifRcvAddressGroup
           DESCRIPTION
               "The applicability of this group MUST be defined by
               the media-specific MIBs.  Media-specific MIBs must
               define the exact meaning, use, and semantics of the
               addresses in this group."

           OBJECT      ifLinkUpDownTrapEnable
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required."

           OBJECT      ifPromiscuousMode
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required."

           OBJECT      ifStackStatus
           SYNTAX      INTEGER { active(1) } -- subset of RowStatus
           MIN-ACCESS  read-only
           DESCRIPTION
               "Write access is not required, and only one of the six
               enumerated values for the RowStatus textual convention
               need be supported, specifically: active(1)."

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           OBJECT       ifAdminStatus
           SYNTAX       INTEGER { up(1), down(2) }
           MIN-ACCESS   read-only
           DESCRIPTION
               "Write access is not required, nor is support for the
               value testing(3)."
       ::= { ifCompliances 1 }

   END

7.  Acknowledgements

   This memo has been produced by the IETF's Interfaces MIB working-
   group.

   The original proposal evolved from conversations and discussions with
   many people, including at least the following: Fred Baker, Ted
   Brunner, Chuck Davin, Jeremy Greene, Marshall Rose, Kaj Tesink, and
   Dean Throop.

8.  References

   [1]  Case, J., McCloghrie, K., Rose, M., and
        S. Waldbusser, "Structure of Management Information for
        version 2 of the Simple Network Management Protocol
        (SNMPv2)", RFC 1902, January 1996.

   [2]  Case, J., McCloghrie, K., Rose, M., and
        S. Waldbusser, "Textual Conventions for version 2 of the
        Simple Network Management Protocol (SNMPv2)", RFC 1903,
        January 1996.

   [3]  Case, J., McCloghrie, K., Rose, M., and
        S. Waldbusser, "Protocol Operations for version 2 of the
        Simple Network Management Protocol (SNMPv2)", RFC 1905,
        January 1996.

   [4]  McCloghrie, K., and M. Rose, "Management Information Base for
        Network Management of TCP/IP-based internets - MIB-II", STD
        17, RFC 1213, March 1991.

   [5]  Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
        Network Management Protocol", STD 15, RFC 1157, May 1990.

   [6]  Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981.

   [7]  McCloghrie, K., "Extensions to the Generic-Interface MIB", RFC
        1229, May 1991.

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   [8]  ATM Forum Technical Committee, "LAN Emulation Client
        Management: Version 1.0 Specification", af-lane-0044.000, ATM
        Forum, September 1995.

   [9]  Stewart, B., "Definitions of Managed Objects for Character
        Stream Devices using SMIv2", RFC 1658, July 1994.

   [10] Bradner, S., "Key words for use in RFCs to Indicate
        Requirements Levels", RFC 2119, March 1997.

9.  Security Considerations

   This MIB contains both readable objects whose values provide the
   number and status of a device's network interfaces, and write-able
   objects which allow an administrator to control the interfaces and to
   perform tests on the interfaces.  Unauthorized access to the readable
   objects is relatively innocuous.  Unauthorized access to the write-
   able objects could cause a denial of service, or in combination with
   other (e.g., physical) security breaches, could cause unauthorized
   connectivity to a device.

10.  Authors' Addresses

   Keith McCloghrie
   Cisco Systems, Inc.
   170 West Tasman Drive
   San Jose, CA  95134-1706

   Phone: 408-526-5260
   EMail: kzm@cisco.com


   Frank Kastenholz
   FTP Software
   2 High Street
   North Andover, Mass. USA 01845

   Phone: 508-685-4000
   EMail: kasten@ftp.com

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11.  Full Copyright Statement

   Copyright (C) The Internet Society (1997).  All Rights Reserved.

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