IF-INVERTED-STACK-MIB DEFINITIONS ::= BEGIN

IMPORTS

  MODULE-IDENTITY, OBJECT-TYPE, mib-2      FROM SNMPv2-SMI

  RowStatus                                FROM SNMPv2-TC

  MODULE-COMPLIANCE, OBJECT-GROUP          FROM SNMPv2-CONF

  ifStackGroup2,

  ifStackHigherLayer, ifStackLowerLayer    FROM IF-MIB;

ifInvertedStackMIB MODULE-IDENTITY

  LAST-UPDATED "200006140000Z"

  ORGANIZATION "IETF Interfaces MIB Working Group"

  CONTACT-INFO

          "   Keith McCloghrie

              Cisco Systems, Inc.

              170 West Tasman Drive

              San Jose, CA  95134-1706

              US

              408-526-5260

              kzm@cisco.com"

  DESCRIPTION

          "The MIB module which provides the Inverted Stack Table for

          interface sub-layers."

  REVISION      "200006140000Z"

  DESCRIPTION

          "Initial revision, published as RFC 2864"

  ::= { mib-2 77 }

ifInvMIBObjects OBJECT IDENTIFIER ::= { ifInvertedStackMIB 1 }

--

--           The Inverted Interface Stack Group

--

ifInvStackTable  OBJECT-TYPE

   SYNTAX        SEQUENCE OF IfInvStackEntry

   MAX-ACCESS    not-accessible

   STATUS        current

   DESCRIPTION

          "A table containing information on the relationships between

          the multiple sub-layers of network interfaces.  In

          particular, it contains information on which sub-layers run

          'underneath' which other sub-layers, where each sub-layer

          corresponds to a conceptual row in the ifTable.  For

          example, when the sub-layer with ifIndex value x runs

          underneath the sub-layer with ifIndex value y, then this

          table contains:

            ifInvStackStatus.x.y=active

          For each ifIndex value, z, which identifies an active

          interface, there are always at least two instantiated rows

          in this table associated with z.  For one of these rows, z

          is the value of ifStackHigherLayer; for the other, z is the

          value of ifStackLowerLayer.  (If z is not involved in

          multiplexing, then these are the only two rows associated

          with z.)

          For example, two rows exist even for an interface which has

          no others stacked on top or below it:

            ifInvStackStatus.z.0=active

            ifInvStackStatus.0.z=active

          This table contains exactly the same number of rows as the

          ifStackTable, but the rows appear in a different order."

   REFERENCE

          "ifStackTable of RFC 2863"

   ::= { ifInvMIBObjects 1 }

ifInvStackEntry  OBJECT-TYPE

   SYNTAX        IfInvStackEntry

   MAX-ACCESS    not-accessible

   STATUS        current

   DESCRIPTION

          "Information on a particular relationship between two sub-

          layers, specifying that one sub-layer runs underneath the

          other sub-layer.  Each sub-layer corresponds to a conceptual

          row in the ifTable."

   INDEX { ifStackLowerLayer, ifStackHigherLayer }

   ::= { ifInvStackTable 1 }

IfInvStackEntry ::=

  SEQUENCE {

      ifInvStackStatus       RowStatus

   }

ifInvStackStatus  OBJECT-TYPE

  SYNTAX         RowStatus

  MAX-ACCESS     read-only

  STATUS         current

  DESCRIPTION

          "The status of the relationship between two sub-layers.

          An instance of this object exists for each instance of the

          ifStackStatus object, and vice versa.  For example, if the

          variable ifStackStatus.H.L exists, then the variable

          ifInvStackStatus.L.H must also exist, and vice versa.  In

          addition, the two variables always have the same value.

          However, unlike ifStackStatus, the ifInvStackStatus object

          is NOT write-able.  A network management application wishing

          to change a relationship between sub-layers H and L cannot

          do so by modifying the value of ifInvStackStatus.L.H, but

          must instead modify the value of ifStackStatus.H.L.  After

          the ifStackTable is modified, the change will be reflected

          in this table."

  ::= { ifInvStackEntry 1 }

-- conformance information

ifInvConformance OBJECT IDENTIFIER ::= { ifInvMIBObjects 2 }

ifInvGroups      OBJECT IDENTIFIER ::= { ifInvConformance 1 }

ifInvCompliances OBJECT IDENTIFIER ::= { ifInvConformance 2 }

-- compliance statements

ifInvCompliance MODULE-COMPLIANCE

  STATUS  current

  DESCRIPTION

          "The compliance statement for SNMP entities which provide

          inverted information on the layering of network interfaces."

  MODULE  -- this module

      MANDATORY-GROUPS { ifInvStackGroup }

      OBJECT       ifInvStackStatus

      SYNTAX       INTEGER { active(1) }

      DESCRIPTION

          "Support is only required for 'active'."

  MODULE  IF-MIB

      MANDATORY-GROUPS { ifStackGroup2 }

  ::= { ifInvCompliances 1 }

-- units of conformance

ifInvStackGroup    OBJECT-GROUP

  OBJECTS { ifInvStackStatus }

  STATUS  current

  DESCRIPTION

          "A collection of objects providing inverted information on

          the layering of MIB-II interfaces."

  ::= { ifInvGroups 1 }

END