Internet Draft                          Editor of this version:
Expires August 2002 December 02                                         K.C. Norseth
draft-ietf-bridge-bridgemib-smiv2-02.txt              Enterasys Networks
draft-ietf-bridge-bridgemib-smiv2-03.txt                      Consultant
Obsoletes: 1493                         Authors of previous version:                                                  E. Bell
                                                              3Com Corp.
                                            Authors of previous version:
                                                               E. Decker
                                                     Cisco Systems, Inc.
                                                             P. Langille
                                                      Newbridge Networks
                                                         A. Rijhsinghani
                                                      Enterasys Networks
                                                           K. McCloghrie
                                                     Cisco Systems, Inc.
                                                           February
                                                                May 2002

               Definitions of Managed Objects for Bridges

Status of this Memo

   This document is an Internet Draft and is in full conformance with
   all provisions of Section 10 of RFC2026. Internet Drafts are working
   documents of the Internet Engineering Task Force (IETF), its Areas,
   and its Working Groups.  Note that other groups may also distribute
   working documents as Internet Drafts.

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Copyright Notice

   Copyright (C) The Internet Society (2002).  All Rights Reserved.

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 MAC bridges based on
   the IEEE 802.1D-1990 802.1D-1998 standard between Local Area Network (LAN)
   segments.  Provisions are made for support of transparent bridging.
   Provisions are also made so that these objects apply to bridges
   connected by subnetworks other than LAN segments.

   The MIB presented in this memo is a direct translation of the BRIDGE
   MIB defined in [RFC1493], to the SMIv2 syntax required for current
   IETF MIB standards.  This memo obsoletes RFC 1493.

1.  The SNMP Management Framework

   The SNMP Management Framework presently consists of five major
   components:

    o   An overall architecture, described in RFC 2571 [RFC2571].

    o   Mechanisms for describing and naming objects and events for the
        purpose of management.  The first version of this Structure of
        Management Information (SMI) is called SMIv1 and described in
        STD 16, RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC
        1215 [RFC1215].  The second version, called SMIv2, is described
        in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and
        STD 58, RFC 2580 [RFC2580].

    o   Message protocols for transferring management information.  The
        first version of the SNMP message protocol is called SNMPv1 and
        described in STD 15, RFC 1157 [RFC1157].  A second version of
        the SNMP message protocol, which is not an Internet standards
        track protocol, is called SNMPv2c and described in RFC 1901
        [RFC1901] and RFC 1906 [RFC1906].  The third version of the
        message protocol is called SNMPv3 and described in RFC 1906
        [RFC1906], RFC 2572 [RFC2572] and RFC 2574 [RFC2574].

    o   Protocol operations for accessing management information.  The
        first set of protocol operations and associated PDU formats is
        described in STD 15, RFC 1157 [RFC1157].  A second set of
        protocol operations and associated PDU formats is described in
        RFC 1905 [RFC1905].

    o   A set of fundamental applications described in RFC 2573
        [RFC2573] and the view-based access control mechanism described
        in RFC 2575 [RFC2575].

   A more detailed introduction to the current SNMP Management Framework
   can be found in RFC 2570 [RFC2570].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the mechanisms defined in the SMI.

   This memo specifies a MIB module that is compliant to the SMIv2.  A
   MIB conforming to the SMIv1 can be produced through the appropriate
   translations.  The resulting translated MIB must be semantically
   equivalent, except where objects or events are omitted because no
   translation is possible (use of Counter64).  Some machine readable
   information in SMIv2 will be converted into textual descriptions in
   SMIv1 during the translation process.  However, this loss of machine
   readable information is not considered to change the semantics of the
   MIB.

2.  Overview

   A common device present in many networks is the Bridge.  This device
   is used to connect Local Area Network segments below the network
   layer.

   There are two major modes defined for this bridging; transparent and
   source route.  The transparent method of bridging is defined in the
   IEEE 802.1D specification [IEEE8021D].  This memo defines those
   objects needed for the management of a bridging entity operating in
   the transparent mode, as well as some objects applicable to all types
   of bridges.

   To be consistent with IAB directives and good engineering practice,
   an explicit attempt was made to keep this MIB as simple as possible.
   This was accomplished by applying the following criteria to objects
   proposed for inclusion:

   (1)  Start with a small set of essential objects and add only as
        further objects are needed.

   (2)  Require objects be essential for either fault or configuration
        management.

   (3)  Consider evidence of current use and/or utility.

   (4)  Limit the total of objects.

   (5)  Exclude objects which are simply derivable from others in this
        or other MIBs.

   (6)  Avoid causing critical sections to be heavily instrumented.  The
        guideline that was followed is one counter per critical section
        per layer.

2.1.  Structure of MIB

   Objects in this MIB are arranged into groups.  Each group is
   organized as a set of related objects.  The overall structure and
   assignment of objects to their groups is shown below.  Where
   appropriate the corresponding IEEE 802.1D [IEEE8021D] management
   object name is also included.

       Bridge MIB Name                  IEEE 802.1D Name

       dot1dBridge
         dot1dBase
           BridgeAddress                Bridge.BridgeAddress
           NumPorts                     Bridge.NumberOfPorts
           Type
           PortTable
             Port                       BridgePort.PortNumber
             IfIndex
             Circuit
             DelayExceededDiscards        .DiscardTransitDelay
             MtuExceededDiscards          .DiscardOnError
         dot1dStp
           ProtocolSpecification
           Priority                     SpanningTreeProtocol
                                          .BridgePriority
           TimeSinceTopologyChange        .TimeSinceTopologyChange
           TopChanges                     .TopologyChangeCount
           DesignatedRoot                 .DesignatedRoot
           RootCost                       .RootCost
           RootPort                       .RootPort
           MaxAge                         .MaxAge
           HelloTime                      .HelloTime
           HoldTime                       .HoldTime
           ForwardDelay                   .ForwardDelay
           BridgeMaxAge                   .BridgeMaxAge
           BridgeHelloTime                .BridgeHelloTime
           BridgeForwardDelay             .BridgeForwardDelay
           PortTable
             Port                        SpanningTreeProtocolPort
                                           .PortNumber
             Priority                      .PortPriority
             State                         .SpanningTreeState
             Enable
             PathCost                      .PortPathCost
             DesignatedRoot                .DesignatedRoot
             DesignatedCost                .DesignatedCost
             DesignatedBridge              .DesignatedBridge
             DesignatedPort                .DesignatedPort
             ForwardTransitions
         dot1dTp
           LearnedEntryDiscards          BridgeFilter.DatabaseSize
                                           .NumDynamic,NumStatic
           AgingTime                     BridgeFilter.AgingTime
           FdbTable
             Address
             Port
             Status
           PortTable
             Port
             MaxInfo
             InFrames                    BridgePort.FramesReceived
             OutFrames                     .ForwardOutbound
             InDiscards                    .DiscardInbound
         dot1dStatic
           StaticTable
             Address
             ReceivePort
             AllowedToGoTo
             Status

   The following IEEE 802.1D management objects have not been included
   in the Bridge MIB for the indicated reasons.

       IEEE 802.1D Object              Disposition

       Bridge.BridgeName               Same as sysDescr (MIB II)
       Bridge.BridgeUpTime             Same as sysUpTime (MIB II)
       Bridge.PortAddresses            Same as ifPhysAddress (MIB II)
       BridgePort.PortName             Same as ifDescr (MIB II)
       BridgePort.PortType             Same as ifType (MIB II)
       BridgePort.RoutingType          Derivable from the implemented
                                       groups

       SpanningTreeProtocol
           .BridgeIdentifier           Combination of dot1dStpPriority
                                       and dot1dBaseBridgeAddress
           .TopologyChange             Since this is transitory, it
                                       is not considered useful.
       SpanningTreeProtocolPort
           .Uptime                     Same as ifLastChange (MIB II)
           .PortIdentifier             Combination of dot1dStpPort
                                       and dot1dStpPortPriority
           .TopologyChangeAcknowledged Since this is transitory, it
                                       is not considered useful.
           .DiscardLackOfBuffers       Redundant

       Transmission Priority           These objects are not required
                                       as per the Pics Proforma and
                                       not considered useful.
           .TransmissionPriorityName
           .OutboundUserPriority
           .OutboundAccessPriority

2.1.1.  The dot1dBase Group

   This mandatory group contains the objects which are applicable to all
   types of bridges.

2.1.2.  The dot1dStp Group

   This group contains the objects that denote the bridge's state with
   respect to the Spanning Tree Protocol.  If a node does not
   implemented the Spanning Tree Protocol, this group will not be
   implemented.

2.1.3.  The dot1dSr Group
   This group contains the objects that describe the entity's state with
   respect to source route bridging.  If source routing is not supported
   this group will not be implemented.  This group is applicable to
   source route only, and SRT bridges.  This group will be described in
   a separate document applicable only to source route bridging.

2.1.4.  The dot1dTp Group

   This group contains objects that describe the entity's state with
   respect to transparent bridging.  If transparent bridging is not
   supported this group will not be implemented.  This group is
   applicable to transparent only and SRT bridges.

2.1.5.  The dot1dStatic Group

   This group contains objects that describe the entity's state with
   respect to destination-address filtering.  If destination-address
   filtering is not supported this group will not be implemented.  This
   group is applicable to any type of bridge which performs destination-
   address filtering.

2.2.  Relationship to Other MIBs

   As described above, some IEEE 802.1D management objects have not been
   included in this MIB because they overlap with objects in other MIBs
   applicable to a bridge implementing this MIB.  In particular, it is
   assumed that a bridge implementing this MIB will also implement (at
   least) the 'system' group and the 'interfaces' group defined in MIB-
   II [RFC1213].

2.2.1.  Relationship to the 'system' group

   In MIB-II [RFC1907], the 'system' group is defined as being mandatory
   for all systems such that each managed entity contains one instance
   of each object in the 'system' group.  Thus, those objects apply to
   the entity as a whole irrespective of whether the entity's sole
   functionality is bridging, or whether bridging is only a subset of
   the entity's functionality.

2.2.2.  Relationship to the 'interfaces' group

   In the Interfaces Group MIB [RFC2863], the 'interfaces' group is
   defined as being mandatory for all systems and contains information
   on an entity's interfaces, where each interface is thought of as
   being attached to a `subnetwork'.  (Note that this term is not to be
   confused with `subnet' which refers to an addressing partitioning
   scheme used in the Internet suite of protocols.) The term 'segment'
   is used in this memo to refer to such a subnetwork, whether it be an
   Ethernet segment, a 'ring', a WAN link, or even an X.25 virtual
   circuit.

   Implicit in this Bridge MIB is the notion of ports on a bridge.  Each
   of these ports is associated with one interface of the 'interfaces'
   group, and in most situations, each port is associated with a
   different interface. However, there are situations in which multiple
   ports are associated with the same interface.  An example of such a
   situation would be several ports each corresponding one-to-one with
   several X.25 virtual circuits but all on the same interface.

   Each port is uniquely identified by a port number.  A port number has
   no mandatory relationship to an interface number, but in the simple
   case a port number will have the same value as the corresponding
   interface's interface number.  Port numbers are in the range
   (1..dot1dBaseNumPorts).

   Some entities perform other functionality as well as bridging through
   the sending and receiving of data on their interfaces.  In such
   situations, only a subset of the data sent/received on an interface
   is within the domain of the entity's bridging functionality.  This
   subset is considered to be delineated according to a set of
   protocols, with some protocols being bridged, and other protocols not
   being bridged. For example, in an entity which exclusively performed
   bridging, all protocols would be considered as being bridged, whereas
   in an entity which performed IP routing on IP datagrams and only
   bridged other protocols, only the non-IP data would be considered as
   being bridged.

   Thus, this Bridge MIB (and in particular, its counters) are
   applicable only to that subset of the data on an entity's interfaces
   which is sent/received for a protocol being bridged.  All such data
   is sent/received via the ports of the bridge.

2.3.  Textual Conventions

   The datatypes, MacAddress, BridgeId and Timeout, are used as textual
   conventions in this document.  Objects defined using these
   conventions are always encoded by means of the rules that define
   their 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.

3.  Definitions

  BRIDGE-MIB DEFINITIONS ::= BEGIN

    -- ---------------------------------------------------------- --
    -- MIB for IEEE 802.1D devices
    -- ---------------------------------------------------------- --
    IMPORTS
        MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
        Counter32, Integer32, TimeTicks, mib-2
            FROM SNMPv2-SMI
        TEXTUAL-CONVENTION, MacAddress
            FROM SNMPv2-TC
        MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
            FROM SNMPv2-CONF
        InterfaceIndex FROM IF-MIB
        ;
    bridgeMIB MODULE-IDENTITY
        LAST-UPDATED "200201310000Z"
        ORGANIZATION "IETF Bridge MIB Working Group"
        CONTACT-INFO
            "Email: Bridge-mib@ietf.org"
        DESCRIPTION
            "The Bridge MIB module for managing devices that support
            IEEE 802.1D."
        REVISION     "200106260000Z"
        DESCRIPTION
             "Translation of RFC 1493 to SMIv2."
        REVISION     "199307310000Z"
        DESCRIPTION
             "RFC 1493: SMIv1 version."
        ::= { dot1dBridge 8 }

dot1dNotification  OBJECT IDENTIFIER ::= { dot1dBridge 0 }

    -- ---------------------------------------------------------- --
    -- Textual Conventions
    -- ---------------------------------------------------------- --

    -- All representations of MAC addresses in this MIB Module use,
    -- as a textual convention (i.e. this convention does not affect
    -- their encoding), the data type MacAddress, defined in
    -- SNMPv2-TC.

    -- Similarly, all representations of Bridge-Id in this MIB
    -- Module use, as a textual convention (i.e. this convention
    -- does not affect their encoding), the data type:

    BridgeId ::= TEXTUAL-CONVENTION
        STATUS      current
        DESCRIPTION
            "The Bridge-Identifier as used in the Spanning Tree
            Protocol to uniquely identify a bridge.  Its first two
            octets (in network byte order) contain a priority value
            and its last 6 octets contain the MAC address used to
            refer to a bridge in a unique fashion (typically, the
            numerically smallest MAC address of all ports on the
            bridge)."
        SYNTAX      OCTET STRING (SIZE (8))

    -- Several objects in this MIB module represent values of timers
    -- used by the Spanning Tree Protocol.  In this MIB, these
    -- timers have values in units of hundreths of a second (i.e.
    -- 1/100 secs).
    -- These timers, when stored in a Spanning Tree Protocol's BPDU,
    -- are in units of 1/256 seconds.  Note, however, that
    -- 802.1D-1990 802.1D-1998 specifies a settable granularity of no more
    -- than 1 second for these timers.  To avoid ambiguity, a data
    -- type is defined here as a textual convention and all
    -- representation of these timers in this MIB module are defined
    -- using this data type.  An algorithm is also defined for
    -- converting between the different units, to ensure a timer's
    -- value is not distorted by multiple conversions.
    -- The data type is:

    Timeout ::= TEXTUAL-CONVENTION
        STATUS      current
        DESCRIPTION
            "A STP timer in units of 1/100 seconds.
            To convert a Timeout value into a value in units of
            1/256 seconds, the following algorithm should be used:

                b = floor( (n * 256) / 100)

            where:
                floor   =  quotient [ignore remainder]
                n is the value in 1/100 second units
                b is the value in 1/256 second units

            To convert the value from 1/256 second units back to
            1/100 seconds, the following algorithm should be used:

                n = ceiling( (b * 100) / 256)

            where:
                ceiling = quotient [if remainder is 0], or
                          quotient + 1 [if remainder is non-zero]
                n is the value in 1/100 second units
                b is the value in 1/256 second units

            Note: it is important that the arithmetic operations are
            done in the order specified (i.e., multiply first,
            divide second)."
        SYNTAX      Integer32

    -- ---------------------------------------------------------- --

    dot1dBridge     OBJECT IDENTIFIER ::= { mib-2 17 }

    -- ---------------------------------------------------------- --
    -- groups in the Bridge MIB
    -- ---------------------------------------------------------- --

    dot1dBase       OBJECT IDENTIFIER ::= { dot1dBridge 1 }
    dot1dStp        OBJECT IDENTIFIER ::= { dot1dBridge 2 }

    dot1dSr         OBJECT IDENTIFIER ::= { dot1dBridge 3 }
    -- separately documented

    dot1dTp         OBJECT IDENTIFIER ::= { dot1dBridge 4 }
    dot1dStatic     OBJECT IDENTIFIER ::= { dot1dBridge 5 }

    -- Groups defined in the Bridge Mib Extensions:

    --      pBridgeMIB MODULE-IDENTITY ::= { dot1dBridge 6 }
    --      qBridgeMIB MODULE-IDENTITY ::= { dot1dBridge 7 }

    -- The MODULE-IDENTITY for this MIB has been defined above as:
    --      bridgeMIB MODULE-IDENTITY ::= { dot1dBridge 8 }

    -- The MODULE-IDENTITY for the Source Routing MIB has been
    -- defined in that MIB as:
    --      srMIB MODULE-IDENTITY ::= { dot1dBridge 9 }

    -- Groups defined in the Source Routing MIB:
    --      dot1dPortPair OBJECT IDENTIFIER ::= { dot1dBridge 10 }

    dot1dConformance        OBJECT IDENTIFIER ::= { bridgeMIB 1 }

    -- ---------------------------------------------------------- --
    -- the dot1dBase group
    -- ---------------------------------------------------------- --
    -- Implementation of the dot1dBase group is mandatory for all
    -- bridges.
    -- ---------------------------------------------------------- --

    dot1dBaseBridgeAddress OBJECT-TYPE
        SYNTAX      MacAddress
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The MAC address used by this bridge when it must be
            referred to in a unique fashion.   It is recommended
            that this be the numerically smallest MAC address of all
            ports that belong to this bridge.  However it is only
            required to be unique.  When concatenated with
            dot1dStpPriority a unique BridgeIdentifier is formed
            which is used in the Spanning Tree Protocol."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Sections 6.4.1.1.3 14.4.1.1.3 and 3.12.5" 7.12.5"
        ::= { dot1dBase 1 }

    dot1dBaseNumPorts OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of ports controlled by this bridging
            entity."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.4.1.1.3" 14.4.1.1.3"
        ::= { dot1dBase 2 }

    dot1dBaseType OBJECT-TYPE
        SYNTAX      INTEGER {
                        unknown(1),
                        transparentOnly(2),
                        sourcerouteOnly(3),
                        srt(4)
                    }
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "Indicates what type of bridging this bridge can
            perform.  If a bridge is actually performing a
            certain type of bridging this will be indicated by
            entries in the port table for the given type."
        ::= { dot1dBase 3 }

    -- ---------------------------------------------------------- --
    -- The Generic Bridge Port Table
    -- ---------------------------------------------------------- --
    dot1dBasePortTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF Dot1dBasePortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A table that contains generic information about every
            port that is associated with this bridge.  Transparent,
            source-route, and srt ports are included."
        ::= { dot1dBase 4 }

    dot1dBasePortEntry OBJECT-TYPE
        SYNTAX      Dot1dBasePortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A list of information for each port of the bridge."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.4.2, 6.6.1" 14.4.2, 14.6.1"
        INDEX  { dot1dBasePort }
        ::= { dot1dBasePortTable 1 }

    Dot1dBasePortEntry ::=
        SEQUENCE {
            dot1dBasePort
                Integer32,
            dot1dBasePortIfIndex
                InterfaceIndex,
            dot1dBasePortCircuit
                OBJECT IDENTIFIER,
            dot1dBasePortDelayExceededDiscards
                Counter32,
            dot1dBasePortMtuExceededDiscards
                Counter32
        }

    dot1dBasePort OBJECT-TYPE
        SYNTAX      Integer32 (1..65535)
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The port number of the port for which this entry
            contains bridge management information."
        ::= { dot1dBasePortEntry 1 }

    dot1dBasePortIfIndex OBJECT-TYPE
        SYNTAX      InterfaceIndex
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The value of the instance of the ifIndex object,
            defined in IF-MIB, for the interface corresponding
            to this port."
        ::= { dot1dBasePortEntry 2 }

    dot1dBasePortCircuit OBJECT-TYPE
        SYNTAX      OBJECT IDENTIFIER
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "For a port which (potentially) has the same value of
            dot1dBasePortIfIndex as another port on the same bridge,
            this object contains the name of an object instance
            unique to this port.  For example, in the case where
            multiple ports correspond one- to-one with multiple X.25
            virtual circuits, this value might identify an (e.g.,
            the first) object instance associated with the X.25
            virtual circuit corresponding to this port.

            For a port which has a unique value of
            dot1dBasePortIfIndex, this object can have the value
            { 0 0 }."
        ::= { dot1dBasePortEntry 3 }

    dot1dBasePortDelayExceededDiscards OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of frames discarded by this port due
            to excessive transit delay through the bridge.  It
            is incremented by both transparent and source
            route bridges."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.6.1.1.3" 14.6.1.1.3"
        ::= { dot1dBasePortEntry 4 }

    dot1dBasePortMtuExceededDiscards OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of frames discarded by this port due
            to an excessive size.  It is incremented by both
            transparent and source route bridges."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.6.1.1.3" 14.6.1.1.3"
        ::= { dot1dBasePortEntry 5 }

    -- ---------------------------------------------------------- --
    -- the dot1dStp group
    -- ---------------------------------------------------------- --
    -- Implementation of the dot1dStp group is optional.  It is
    -- implemented by those bridges that support the Spanning Tree
    -- Protocol.
    -- ---------------------------------------------------------- --

    dot1dStpProtocolSpecification OBJECT-TYPE
        SYNTAX      INTEGER {
                        unknown(1),
                        decLb100(2),
                        ieee8021d(3)
                    }
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "An indication of what version of the Spanning Tree
            Protocol is being run.  The value 'decLb100(2)'
            indicates the DEC LANbridge 100 Spanning Tree protocol.
            IEEE 802.1D implementations will return 'ieee8021d(3)'.
            If future versions of the IEEE Spanning Tree Protocol
            are released that are incompatible with the current
            version a new value will be defined."
        ::= { dot1dStp 1 }

    dot1dStpPriority OBJECT-TYPE
        SYNTAX      Integer32 (0..65535)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The value of the write-able portion of the Bridge ID,
            i.e., the first two octets of the (8 octet long) Bridge
            ID.  The other (last) 6 octets of the Bridge ID are
            given by the value of dot1dBaseBridgeAddress.
            Permissible values are 0-61440, in steps of 4096."
        REFERENCE
            " IEEE 802.1t clause 8.10.2, Table 8-4, clause 14.3."
        ::= { dot1dStp 2 }

    dot1dStpTimeSinceTopologyChange OBJECT-TYPE
        SYNTAX      TimeTicks
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The time (in hundredths of a second) since the
            last time a topology change was detected by the
            bridge entity.
            For RSTP, this reports the time since the tcWhile timer for
            any port on this Bridge was non-zero."
        REFERENCE
            " IEEE 802.1w clause 14.8.1.1."
        ::= { dot1dStp 3 }

    dot1dStpTopChanges OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The total number of topology changes detected by
            this bridge since the management entity was last
            reset or initialized."
        REFERENCE
            " IEEE 802.1w clause 14.8.1.1."
        ::= { dot1dStp 4 }

    dot1dStpDesignatedRoot OBJECT-TYPE
        SYNTAX      BridgeId
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The bridge identifier of the root of the spanning
            tree as determined by the Spanning Tree Protocol
            as executed by this node.  This value is used as
            the Root Identifier parameter in all Configuration
            Bridge PDUs originated by this node."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.1" 8.5.3.1"
        ::= { dot1dStp 5 }

    dot1dStpRootCost OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The cost of the path to the root as seen from
            this bridge."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.2" 8.5.3.2"
        ::= { dot1dStp 6 }

    dot1dStpRootPort OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The port number of the port which offers the lowest
            cost path from this bridge to the root bridge."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.3" 8.5.3.3"
        ::= { dot1dStp 7 }

    dot1dStpMaxAge OBJECT-TYPE
        SYNTAX      Timeout
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The maximum age of Spanning Tree Protocol information
            learned from the network on any port before it is
            discarded, in units of hundredths of a second.  This is
            the actual value that this bridge is currently using."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.4" 8.5.3.4"
        ::= { dot1dStp 8 }

    dot1dStpHelloTime OBJECT-TYPE
        SYNTAX      Timeout
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The amount of time between the transmission of
            Configuration bridge PDUs by this node on any port when
            it is the root of the spanning tree or trying to become
            so, in units of hundredths of a second.  This is the
            actual value that this bridge is currently using."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.5" 8.5.3.5"
        ::= { dot1dStp 9 }

    dot1dStpHoldTime OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "This time value determines the interval length
            during which no more than two Configuration bridge
            PDUs shall be transmitted by this node, in units
            of hundredths of a second."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.14" 8.5.3.14"
        ::= { dot1dStp 10 }

    dot1dStpForwardDelay OBJECT-TYPE
        SYNTAX      Timeout
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "This time value, measured in units of hundredths of a
            second, controls how fast a port changes its spanning
            state when moving towards the Forwarding state.  The
            value determines how long the port stays in each of the
            Listening and Learning states, which precede the
            Forwarding state.  This value is also used, when a
            topology change has been detected and is underway, to
            age all dynamic entries in the Forwarding Database.
            [Note that this value is the one that this bridge is
            currently using, in contrast to
            dot1dStpBridgeForwardDelay which is the value that this
            bridge and all others would start using if/when this
            bridge were to become the root.]"
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.6" 8.5.3.6"
        ::= { dot1dStp 11 }

    dot1dStpBridgeMaxAge OBJECT-TYPE
        SYNTAX      Timeout (600..4000)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The value that all bridges use for MaxAge when this
            bridge is acting as the root.  Note that 802.1D-1990 802.1D-1998
            specifies that the range for this parameter is related
            to the value of dot1dStpBridgeHelloTime.  The
            granularity of this timer is specified by 802.1D-1990 802.1D-1998 to
            be 1 second.  An agent may return a badValue error if a
            set is attempted to a value which is not a whole number
            of seconds."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.8" 8.5.3.8"
        ::= { dot1dStp 12 }

    dot1dStpBridgeHelloTime OBJECT-TYPE
        SYNTAX      Timeout (100..1000)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The value that all bridges use for HelloTime when this
            bridge is acting as the root.  The granularity of this
            timer is specified by 802.1D- 1990 802.1D-1998 to be 1 second.  An
            agent may return a badValue error if a set is attempted
            to a value which is not a whole number of seconds."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.9" 8.5.3.9"
        ::= { dot1dStp 13 }

    dot1dStpBridgeForwardDelay OBJECT-TYPE
        SYNTAX      Timeout (400..3000)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The value that all bridges use for ForwardDelay when
            this bridge is acting as the root.  Note that
            802.1D-1990
            802.1D-1998 specifies that the range for this parameter
            is related to the value of dot1dStpBridgeMaxAge.  The
            granularity of this timer is specified by 802.1D-1990 802.1D-1998 to
            be 1 second.  An agent may return a badValue error if a
            set is attempted to a value which is not a whole number
            of seconds."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.3.10" 8.5.3.10"
        ::= { dot1dStp 14 }
    -- ---------------------------------------------------------- --
    -- The Spanning Tree Port Table
    -- ---------------------------------------------------------- --

    dot1dStpPortTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF Dot1dStpPortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A table that contains port-specific information
            for the Spanning Tree Protocol."
        ::= { dot1dStp 15 }

    dot1dStpPortEntry OBJECT-TYPE
        SYNTAX      Dot1dStpPortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A list of information maintained by every port about
            the Spanning Tree Protocol state for that port."
        INDEX   { dot1dStpPort }
        ::= { dot1dStpPortTable 1 }

    Dot1dStpPortEntry ::=
        SEQUENCE {
            dot1dStpPort
                Integer32,
            dot1dStpPortPriority
                Integer32,
            dot1dStpPortState
                INTEGER,
            dot1dStpPortEnable
                INTEGER,
            dot1dStpPortPathCost
                INTEGER,
            dot1dStpPortDesignatedRoot
                BridgeId,
            dot1dStpPortDesignatedCost
                Integer32,
            dot1dStpPortDesignatedBridge
                BridgeId,
            dot1dStpPortDesignatedPort
                OCTET STRING,
            dot1dStpPortForwardTransitions
                Counter32,
            dot1dStpPortPathCost32
                Integer32
        }

    dot1dStpPort OBJECT-TYPE
        SYNTAX      Integer32 (1..65535)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The port number of the port for which this entry
            contains Spanning Tree Protocol management information."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.8.2.1.2" 14.8.2.1.2"
        ::= { dot1dStpPortEntry 1 }

    dot1dStpPortPriority OBJECT-TYPE
        SYNTAX Integer32 (0.. 255)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The value of the priority field which is contained in
            the first (in network byte order) octet of the (2 octet
            long) Port ID.  The other octet of the Port ID is given
            by the value of dot1dStpPort.
            On newer bridges, permissible values are
            0-240, in steps of 16."
        REFERENCE
            " IEEE 802.1t clause 8.10.2, Table 8-4, clause 14.3."
        ::= { dot1dStpPortEntry 2 }

    dot1dStpPortState OBJECT-TYPE
        SYNTAX      INTEGER {
                        disabled(1),
                        blocking(2),
                        listening(3),
                        learning(4),
                        forwarding(5),
                        broken(6)
                    }
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The port's current state as defined by application of
            the Spanning Tree Protocol.  This state controls what
            action a port takes on reception of a frame.  If the
            bridge has detected a port that is malfunctioning it
            will place that port into the broken(6) state.  For
            ports which are disabled (see dot1dStpPortEnable), this
            object will have a value of disabled(1)."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.2" 8.5.5.2"
        ::= { dot1dStpPortEntry 3 }

    dot1dStpPortEnable OBJECT-TYPE
        SYNTAX      INTEGER {
                        enabled(1),
                        disabled(2)
                    }
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The enabled/disabled status of the port."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.2" 8.5.5.2"
        ::= { dot1dStpPortEntry 4 }

    dot1dStpPortPathCost OBJECT-TYPE
        SYNTAX  INTEGER (1..65535)
        MAX-ACCESS  read-write
        STATUS  deprecated
        DESCRIPTION
                "The contribution of this port to the path cost of
                paths towards the spanning tree root which include
                this port.  802.1D-1990  802.1D-1998 recommends that the
                default value of this parameter be in inverse
                proportion to the speed of the attached LAN.

                New implementations should use dot1dStpPortPathCost32"
        REFERENCE
                "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.3" 8.5.5.3"
        ::= { dot1dStpPortEntry 5 }

    dot1dStpPortDesignatedRoot OBJECT-TYPE
        SYNTAX      BridgeId
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The unique Bridge Identifier of the Bridge
            recorded as the Root in the Configuration BPDUs
            transmitted by the Designated Bridge for the
            segment to which the port is attached."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.4" 8.5.5.4"
        ::= { dot1dStpPortEntry 6 }

    dot1dStpPortDesignatedCost OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The path cost of the Designated Port of the segment
            connected to this port.  This value is compared to the
            Root Path Cost field in received bridge PDUs."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.5" 8.5.5.5"
        ::= { dot1dStpPortEntry 7 }

    dot1dStpPortDesignatedBridge OBJECT-TYPE
        SYNTAX      BridgeId
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The Bridge Identifier of the bridge which this
            port considers to be the Designated Bridge for
            this port's segment."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.6" 8.5.5.6"
        ::= { dot1dStpPortEntry 8 }

    dot1dStpPortDesignatedPort OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (2))
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The Port Identifier of the port on the Designated
            Bridge for this port's segment."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 4.5.5.7" 8.5.5.7"
        ::= { dot1dStpPortEntry 9 }

    dot1dStpPortForwardTransitions OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of times this port has transitioned
            from the Learning state to the Forwarding state."
        ::= { dot1dStpPortEntry 10 }

    dot1dStpPortPathCost32 OBJECT-TYPE
        SYNTAX      Integer32 (1..200000000)
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
            "The contribution of this port to the path cost of
            paths towards the spanning tree root which include
            this port.  802.1D-1990  802.1D-1998 recommends that the
            default value of this parameter be in inverse
            proportion to the speed of the attached LAN.
            The permissible values must be extended to 1-200,000,000.

            Replacement for deprecated object dot1dStpPortPathCost"
        REFERENCE
            " IEEE 802.1t clause 8.10.2, Table 8-5."
        ::= { dot1dStpPortEntry 11 }

    -- ---------------------------------------------------------- --
    -- the dot1dTp group
    -- ---------------------------------------------------------- --
    -- Implementation of the dot1dTp group is optional.  It is
    -- implemented by those bridges that support the transparent
    -- bridging mode.  A transparent or SRT bridge will implement
    -- this group.
    -- ---------------------------------------------------------- --

    dot1dTpLearnedEntryDiscards OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The total number of Forwarding Database entries, which
            have been or would have been learnt, but have been
            discarded due to a lack of space to store them in the
            Forwarding Database.  If this counter is increasing, it
            indicates that the Forwarding Database is regularly
            becoming full (a condition which has unpleasant
            performance effects on the subnetwork).  If this counter
            has a significant value but is not presently increasing,
            it indicates that the problem has been occurring but is
            not persistent."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.7.1.1.3" 14.7.1.1.3"
        ::= { dot1dTp 1 }

    dot1dTpAgingTime OBJECT-TYPE
        SYNTAX       Integer32 (10..1000000)
        MAX-ACCESS   read-write
        STATUS       current
        DESCRIPTION
            "The timeout period in seconds for aging out
            dynamically learned forwarding information.
            802.1D-1990
            802.1D-1998 recommends a default of 300 seconds."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.7.1.1.3" 14.7.1.1.3"
        ::= { dot1dTp 2 }

    -- ---------------------------------------------------------- --
    --  The Forwarding Database for Transparent Bridges
    -- ---------------------------------------------------------- --

    dot1dTpFdbTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF Dot1dTpFdbEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A table that contains information about unicast
            entries for which the bridge has forwarding and/or
            filtering information.  This information is used
            by the transparent bridging function in
            determining how to propagate a received frame."
        ::= { dot1dTp 3 }

    dot1dTpFdbEntry OBJECT-TYPE
        SYNTAX      Dot1dTpFdbEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "Information about a specific unicast MAC address
            for which the bridge has some forwarding and/or
            filtering information."
        INDEX   { dot1dTpFdbAddress }
        ::= { dot1dTpFdbTable 1 }

    Dot1dTpFdbEntry ::=
        SEQUENCE {
            dot1dTpFdbAddress
                MacAddress,
            dot1dTpFdbPort
                Integer32,
            dot1dTpFdbStatus
                INTEGER
        }

    dot1dTpFdbAddress OBJECT-TYPE
        SYNTAX      MacAddress
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "A unicast MAC address for which the bridge has
            forwarding and/or filtering information."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 3.9.1, 3.9.2" 7.9.1, 7.9.2"
        ::= { dot1dTpFdbEntry 1 }

    dot1dTpFdbPort OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "Either the value '0', or the port number of the port on
            which a frame having a source address equal to the value
            of the corresponding instance of dot1dTpFdbAddress has
            been seen.  A value of '0' indicates that the port
            number has not been learned but that the bridge does
            have some forwarding/filtering information about this
            address (e.g. in the dot1dStaticTable).  Implementors
            are encouraged to assign the port value to this object
            whenever it is learned even for addresses for which the
            corresponding value of dot1dTpFdbStatus is not
            learned(3)."
        ::= { dot1dTpFdbEntry 2 }

    dot1dTpFdbStatus OBJECT-TYPE
        SYNTAX      INTEGER {
                        other(1),
                        invalid(2),
                        learned(3),
                        self(4),
                        mgmt(5)
                    }
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The status of this entry.  The meanings of the
            values are:
                other(1) - none of the following.  This would
                    include the case where some other MIB object
                    (not the corresponding instance of
                    dot1dTpFdbPort, nor an entry in the
                    dot1dStaticTable) is being used to determine if
                    and how frames addressed to the value of the
                    corresponding instance of dot1dTpFdbAddress are
                    being forwarded.
                invalid(2) - this entry is not longer valid (e.g.,
                    it was learned but has since aged-out), but has
                    not yet been flushed from the table.
                learned(3) - the value of the corresponding instance
                    of dot1dTpFdbPort was learned, and is being
                    used.
                self(4) - the value of the corresponding instance of
                    dot1dTpFdbAddress represents one of the bridge's
                    addresses.  The corresponding instance of
                    dot1dTpFdbPort indicates which of the bridge's
                    ports has this address.
                mgmt(5) - the value of the corresponding instance of
                    dot1dTpFdbAddress is also the value of an
                    existing instance of dot1dStaticAddress."
        ::= { dot1dTpFdbEntry 3 }

    -- ---------------------------------------------------------- --
    --  Port Table for Transparent Bridges
    -- ---------------------------------------------------------- --

    dot1dTpPortTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF Dot1dTpPortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A table that contains information about every port that
            is associated with this transparent bridge."
        ::= { dot1dTp 4 }

    dot1dTpPortEntry OBJECT-TYPE
        SYNTAX      Dot1dTpPortEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A list of information for each port of a transparent
            bridge."
        INDEX   { dot1dTpPort }
        ::= { dot1dTpPortTable 1 }

    Dot1dTpPortEntry ::=
        SEQUENCE {
            dot1dTpPort
                Integer32,
            dot1dTpPortMaxInfo
                Integer32,
            dot1dTpPortInFrames
                Counter32,
            dot1dTpPortOutFrames
                Counter32,
            dot1dTpPortInDiscards
                Counter32
        }

    dot1dTpPort OBJECT-TYPE
        SYNTAX      Integer32 (1..65535)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The port number of the port for which this entry
            contains Transparent bridging management information."
        ::= { dot1dTpPortEntry 1 }

    -- It would be nice if we could use ifMtu as the size of the
    -- largest INFO field, but we can't because ifMtu is defined
    -- to be the size that the (inter-)network layer can use which
    -- can differ from the MAC layer (especially if several layers
    -- of encapsulation are used).

    dot1dTpPortMaxInfo OBJECT-TYPE
        SYNTAX      Integer32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The maximum size of the INFO (non-MAC) field that
            this port will receive or transmit."
        ::= { dot1dTpPortEntry 2 }

    dot1dTpPortInFrames OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of frames that have been received by this
            port from its segment. Note that a frame received on the
            interface corresponding to this port is only counted by
            this object if and only if it is for a protocol being
            processed by the local bridging function, including
            bridge management frames."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.6.1.1.3" 14.6.1.1.3"
        ::= { dot1dTpPortEntry 3 }

    dot1dTpPortOutFrames OBJECT-TYPE
        SYNTAX      Counter32
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The number of frames that have been transmitted by this
            port to its segment.  Note that a frame transmitted on
            the interface corresponding to this port is only counted
            by this object if and only if it is for a protocol being
            processed by the local bridging function, including
            bridge management frames."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.6.1.1.3" 14.6.1.1.3"
        ::= { dot1dTpPortEntry 4 }

    dot1dTpPortInDiscards OBJECT-TYPE
        SYNTAX       Counter32
        MAX-ACCESS   read-only
        STATUS       current
        DESCRIPTION
            "Count of valid frames received which were discarded
            (i.e., filtered) by the Forwarding Process."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.6.1.1.3" 14.6.1.1.3"
        ::= { dot1dTpPortEntry 5 }

    -- ---------------------------------------------------------- --
    -- The Static (Destination-Address Filtering) Database
    -- ---------------------------------------------------------- --
    -- Implementation of this group is optional.
    -- ---------------------------------------------------------- --

    dot1dStaticTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF Dot1dStaticEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A table containing filtering information configured
            into the bridge by (local or network) management
            specifying the set of ports to which frames received
            from specific ports and containing specific destination
            addresses are allowed to be forwarded.  The value of
            zero in this table as the port number from which frames
            with a specific destination address are received, is
            used to specify all ports for which there is no specific
            entry in this table for that particular destination
            address.  Entries are valid for unicast and for
            group/broadcast addresses."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.7.2" 14.7.2"
        ::= { dot1dStatic 1 }

    dot1dStaticEntry OBJECT-TYPE
        SYNTAX      Dot1dStaticEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "Filtering information configured into the bridge by
            (local or network) management specifying the set of
            ports to which frames received from a specific port and
            containing a specific destination address are allowed to
            be forwarded."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 6.7.2" 14.7.2"
        INDEX   { dot1dStaticAddress, dot1dStaticReceivePort }
        ::= { dot1dStaticTable 1 }
    Dot1dStaticEntry ::=
        SEQUENCE {
            dot1dStaticAddress       MacAddress,
            dot1dStaticReceivePort   Integer32,
            dot1dStaticAllowedToGoTo OCTET STRING,
            dot1dStaticStatus        INTEGER
        }

    dot1dStaticAddress OBJECT-TYPE
        SYNTAX      MacAddress
      MAX-ACCESS read-create
        STATUS      current
        DESCRIPTION
            "The destination MAC address in a frame to which this
            entry's filtering information applies.  This object can
            take the value of a unicast address, a group address or
            the broadcast address."
        REFERENCE
            "IEEE 802.1D-1990: 802.1D-1998: Section 3.9.1, 3.9.2" 7.9.1, 7.9.2"
        ::= { dot1dStaticEntry 1 }

    dot1dStaticReceivePort OBJECT-TYPE
        SYNTAX      Integer32 (0..65535)
        MAX-ACCESS read-create
        STATUS      current
        DESCRIPTION
            "Either the value '0', or the port number of the port
            from which a frame must be received in order for this
            entry's filtering information to apply.  A value of zero
            indicates that this entry applies on all ports of the
            bridge for which there is no other applicable entry."
        ::= { dot1dStaticEntry 2 }

    dot1dStaticAllowedToGoTo OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0..512))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The set of ports to which frames received from a
            specific port and destined for a specific MAC address,
            are allowed to be forwarded.  Each octet within the
            value of this object specifies a set of eight ports,
            with the first octet specifying ports 1 through 8, the
            second octet specifying ports 9 through 16, etc.  Within
            each octet, the most significant bit represents the
            lowest numbered port, and the least significant bit
            represents the highest numbered port.  Thus, each port
            of the bridge is represented by a single bit within the
            value of this object.  If that bit has a value of '1'
            then that port is included in the set of ports; the port
            is not included if its bit has a value of '0'.  (Note
            that the setting of the bit corresponding to the port
            from which a frame is received is irrelevant.)  The
            default value of this object is a string of ones of
            appropriate length.

            This exceeds the minimum required SNMP packet size
            supported.  This is sufficient to allow the maximum
            4096 ports now supported."
        ::= { dot1dStaticEntry 3 }

    dot1dStaticStatus OBJECT-TYPE
        SYNTAX      INTEGER {
                        other(1),
                        invalid(2),
                        permanent(3),
                        deleteOnReset(4),
                        deleteOnTimeout(5)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object indicates the status of this entry.
            The default value is permanent(3).
                other(1) - this entry is currently in use but the
                    conditions under which it will remain so are
                    different from each of the following values.
                invalid(2) - writing this value to the object
                    removes the corresponding entry.
                permanent(3) - this entry is currently in use and
                    will remain so after the next reset of the
                    bridge.
                deleteOnReset(4) - this entry is currently in use
                    and will remain so until the next reset of the
                    bridge.
                deleteOnTimeout(5) - this entry is currently in use
                    and will remain so until it is aged out."
        ::= { dot1dStaticEntry 4 }

    -- ---------------------------------------------------------- --
    -- Notifications for use by Bridges
    -- ---------------------------------------------------------- --
    -- Notifications for the Spanning Tree Protocol
    -- ---------------------------------------------------------- --

    newRoot NOTIFICATION-TYPE
        -- OBJECTS     { }
        STATUS      current
        DESCRIPTION
            "The newRoot trap indicates that the sending agent has
            become the new root of the Spanning Tree; the trap is
            sent by a bridge soon after its election as the new
            root, e.g., upon expiration of the Topology Change Timer
            immediately subsequent to its election.  Implementation
            of this trap is optional."
    ::= { dot1dNotification 1 }
    topologyChange NOTIFICATION-TYPE
        -- OBJECTS     { }
        STATUS      current
        DESCRIPTION
            "A topologyChange trap is sent by a bridge when any of
            its configured ports transitions from the Learning state
            to the Forwarding state, or from the Forwarding state to
            the Blocking state.  The trap is not sent if a newRoot
            trap is sent for the same transition.  Implementation of
            this trap is optional."
    ::= { dot1dNotification 2 }

    -- ---------------------------------------------------------- --
    -- IEEE 802.1D MIB - Conformance Information
    -- ---------------------------------------------------------- --

    dot1dGroups         OBJECT IDENTIFIER ::= { dot1dConformance 1 }
    dot1dCompliances    OBJECT IDENTIFIER ::= { dot1dConformance 2 }

    -- ---------------------------------------------------------- --
    -- units of conformance
    -- ---------------------------------------------------------- --

    -- ---------------------------------------------------------- --
    -- the dot1dBase group
    -- ---------------------------------------------------------- --

    dot1dBaseBridgeGroup OBJECT-GROUP
        OBJECTS {
            dot1dBaseBridgeAddress,
            dot1dBaseNumPorts,
            dot1dBaseType
        }
        STATUS      current
        DESCRIPTION
            "Bridge level information for this device."
        ::= { dot1dGroups 1 }

    dot1dBasePortGroup OBJECT-GROUP
        OBJECTS {
            dot1dBasePortIfIndex,
            dot1dBasePortCircuit,
            dot1dBasePortDelayExceededDiscards,
            dot1dBasePortMtuExceededDiscards
        }
        STATUS      current
        DESCRIPTION
            "Information for each port on this device."
        ::= { dot1dGroups 2 }

    -- ---------------------------------------------------------- --
    -- the dot1dStp group
    -- ---------------------------------------------------------- --
    dot1dStpBridgeGroup OBJECT-GROUP
        OBJECTS {
            dot1dStpProtocolSpecification,
            dot1dStpPriority,
            dot1dStpTimeSinceTopologyChange,
            dot1dStpTopChanges,
            dot1dStpDesignatedRoot,
            dot1dStpRootCost,
            dot1dStpRootPort,
            dot1dStpMaxAge,
            dot1dStpHelloTime,
            dot1dStpHoldTime,
            dot1dStpForwardDelay,
            dot1dStpBridgeMaxAge,
            dot1dStpBridgeHelloTime,
            dot1dStpBridgeForwardDelay
        }
        STATUS      current
        DESCRIPTION
            "Bridge level Spanning Tree data for this device."
        ::= { dot1dGroups 3 }

    dot1dStpPortGroup OBJECT-GROUP
        OBJECTS {
            dot1dStpPortPriority,
            dot1dStpPortState,
            dot1dStpPortEnable,
            dot1dStpPortPathCost,
            dot1dStpPortDesignatedRoot,
            dot1dStpPortDesignatedCost,
            dot1dStpPortDesignatedBridge,
            dot1dStpPortDesignatedPort,
            dot1dStpPortForwardTransitions
        }
        STATUS      current
        DESCRIPTION
            "Spanning Tree data for each port on this device."
        ::= { dot1dGroups 4 }

    -- ---------------------------------------------------------- --
    -- the dot1dTp group
    -- ---------------------------------------------------------- --

    dot1dTpBridgeGroup OBJECT-GROUP
        OBJECTS {
            dot1dTpLearnedEntryDiscards,
            dot1dTpAgingTime
        }
        STATUS      current
        DESCRIPTION
            "Bridge level Transparent Bridging data."
        ::= { dot1dGroups 5 }

    dot1dTpFdbGroup OBJECT-GROUP
        OBJECTS {
            dot1dTpFdbPort,
            dot1dTpFdbStatus
        }
        STATUS      current
        DESCRIPTION
            "Filtering Database information for the Bridge."
        ::= { dot1dGroups 6 }

    dot1dTpGroup OBJECT-GROUP
        OBJECTS {
            dot1dTpPortMaxInfo,
            dot1dTpPortInFrames,
            dot1dTpPortOutFrames,
            dot1dTpPortInDiscards
        }
        STATUS      current
        DESCRIPTION
            "Dynamic Filtering Database information for each port of
            the Bridge."
        ::= { dot1dGroups 7 }

    -- ---------------------------------------------------------- --
    -- The Static (Destination-Address Filtering) Database
    -- ---------------------------------------------------------- --

    dot1dStaticGroup OBJECT-GROUP
        OBJECTS {
            dot1dStaticAllowedToGoTo,
            dot1dStaticStatus
        }
        STATUS      current
        DESCRIPTION
            "Static Filtering Database information for each port of
            the Bridge."
        ::= { dot1dGroups 8 }

    -- ---------------------------------------------------------- --
    -- The Trap Notfication Group
    -- ---------------------------------------------------------- --

    dot1dNotificationGroup NOTIFICATION-GROUP
        NOTIFICATIONS {
            newRoot,
            topologyChange
        }
        STATUS      current
        DESCRIPTION
            "Group of objects describing notifications (traps)."
        ::= { dot1dGroups 9 }

    -- ---------------------------------------------------------- --
    -- compliance statements
    -- ---------------------------------------------------------- --
    bridgeCompliance MODULE-COMPLIANCE
        STATUS      current
        DESCRIPTION
            "The compliance statement for device support of bridging
            services."

        MODULE
            MANDATORY-GROUPS {
                dot1dBaseBridgeGroup,
                dot1dBasePortGroup
            }

            GROUP   dot1dStpBridgeGroup
            DESCRIPTION
                "Implementation of this group is mandatory for
                bridges that support the Spanning Tree Protocol."

            GROUP   dot1dStpPortGroup
            DESCRIPTION
                "Implementation of this group is mandatory for
                bridges that support the Spanning Tree Protocol."

            GROUP   dot1dTpBridgeGroup
            DESCRIPTION
                "Implementation of this group is mandatory for
                bridges that support the transparent bridging
                mode.  A transparent or SRT bridge will implement
                this group."

            GROUP   dot1dTpFdbGroup
            DESCRIPTION
                "Implementation of this group is mandatory for
                bridges that support the transparent bridging
                mode.  A transparent or SRT bridge will implement
                this group."

            GROUP   dot1dTpGroup
            DESCRIPTION
                "Implementation of this group is mandatory for
                bridges that support the transparent bridging
                mode.  A transparent or SRT bridge will implement
                this group."

            GROUP   dot1dStaticGroup
            DESCRIPTION
                "Implementation of this group is optional."

            GROUP dot1dNotificationGroup
            DESCRIPTION
                "Implementation of this group is optional."
            ::= { dot1dCompliances 1 }

END

4.  Security Considerations

   There are a number of management objects defined in this MIB that
   have a MAX-ACCESS clause of read-write and/or read-create.  Such
   objects may be considered sensitive or vulnerable in some network
   environments.  The support for SET operations in a non-secure
   environment without proper protection can have a negative effect on
   network operations.

   SNMPv1 by itself is not a secure environment.  Even if the network
   itself is secure (for example by using IPSec), even then, there is no
   control as to who on the secure network is allowed to access and
   GET/SET (read/change/create/delete) the objects in this MIB.

   It is recommended that the implementers consider the security
   features as provided by the SNMPv3 framework.  Specifically, the use
   of the User-based Security Model RFC 2574 [RFC2574] and the View-
   based Access Control Model RFC 2575 [RFC2575] is recommended.

   It is then a customer/user responsibility to ensure that the SNMP
   entity giving access to an instance of this MIB, is properly
   configured to give access to the objects only to those principals
   (users) that have legitimate rights to indeed GET or SET
   (change/create/delete) them.

5.  Acknowledgments

   The MIB presented in this memo is a direct translation of the BRIDGE
   MIB defined in [RFC1493], to the SMIv2 syntax required for current
   IETF MIB standards.

   The original authors were E. Decker, P. Langille, A Rijsinghani and
   K. McCloghrie.  Further acknowledgement is given to the members of
   the original Bridge Working Group in [RFC1493].

   This document was produced on behalf of the Bridge MIB Working Group
   in the Operations and Management area of the Internet Engineering
   Task Force.

   The authors wish to thank the members of the Bridge MIB Working Group
   for their many comments and suggestions which improved this effort.

6.  References

[RFC2571]   Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture
            for Describing SNMP Management Frameworks", RFC 2571, April
            1999.

[RFC1155]   Rose, M., and K. McCloghrie, "Structure and Identification
            of Management Information for TCP/IP-based Internets", STD
            16, RFC 1155, May 1990.

[RFC1212]   Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD
            16, RFC 1212, March 1991.

[RFC1215]   M. Rose, "A Convention for Defining Traps for use with the
            SNMP", RFC 1215, March 1991.

[RFC2578]   McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
            Rose, M., and S. Waldbusser, "Structure of Management
            Information Version 2 (SMIv2)", STD 58, RFC 2578, April
            1999.

[RFC2579]   McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
            Rose, M., and S. Waldbusser, "Textual Conventions for
            SMIv2", STD 58, RFC 2579, April 1999.

[RFC2580]   McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
            Rose, M., and S. Waldbusser, "Conformance Statements for
            SMIv2", STD 58, RFC 2580, April 1999.

[RFC1157]   Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
            Network Management Protocol", STD 15, RFC 1157, May 1990.

[RFC1901]   Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
            "Introduction to Community-based SNMPv2", RFC 1901, January
            1996.

[RFC1906]   Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
            "Transport Mappings for Version 2 of the Simple Network
            Management Protocol (SNMPv2)", RFC 1906, January 1996.

[RFC2572]   Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message
            Processing and Dispatching for the Simple Network Management
            Protocol (SNMP)", RFC 2572, April 1999.

[RFC2574]   Blumenthal, U., and B. Wijnen, "User-based Security Model
            (USM) for version 3 of the Simple Network Management
            Protocol (SNMPv3)", RFC 2574, April 1999.

[RFC1905]   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.

[RFC2573]   Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications",
            RFC 2573, April 1999.

[RFC2575]   Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based
            Access Control Model (VACM) for the Simple Network
            Management Protocol (SNMP)", RFC 2575, April 1999.

[RFC2570]   Case, J., Mundy, R., Partain, D., and B. Stewart,
            "Introduction to Version 3 of the Internet-standard Network
            Management Framework", RFC 2570, April 1999.

[IEEE8021D] ANSI/IEEE Standard 802.1D-1990 802.1D-1998 MAC Bridges, IEEE Project 802
            Local and Metropolitan Area Networks, (March 8, 1991). 1998).

[ISO8021D]  ISO DIS 10038 MAC Bridges.

[RFC2863]   McCloghrie, K. and F. Kastenholz, "The Interfaces Group
            MIB", RFC 2863, June 2000.

[RFC1907]   Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
            "Management Information Base for Version 2 of the Simple
            Network Management Protocol (SNMPv2)", RFC 1907, January

            1996.

7.  Changes from RFC 1493

   The following changes have been made from RFC 1493.

 (1)   Translated the MIB definition to use SMIv2.

 (2)   Updated the SNMP Framework and references to comply with the
       current IETF guidelines.

 (3)   Updated the Security section to comply with current IETF
       guidelines.

    The following chnages have been made from
        draft-ietf-bridge-bridgemib-smiv2-00.txt

 (1)   Misc. description refernces to IEEE 802.1d documents

 (2)   dot1dNotificationGroup changed from dot1dTrapGroup

 (3)   Misc. additions to some descriptions

    The following chnages have been made from
        draft-ietf-bridge-bridgemib-smiv2-01.txt

 (1)   corrections to objects that were made not-accessible in the
       draft-00 version that were read /read-write in rfc 1493

 (2)   Misc. additions to some descriptions

    The following chnages have been made from
        draft-ietf-bridge-bridgemib-smiv2-02.txt

 (1)   Updated references of IEEE 802.1d draft from
       1990 document to 1998 document.

8.  Authors' Addresses
   K.C. Norseth
   Enterasys Networks
   2691
   Consultant
   934 S. Decker Lake Lane
   Salt Lake City, Palos Verdes Dr.
   Kaysville, Utah 84119 84037
   Phone: +1 801 887 9823 546 3316
   Email: knorseth@enterasys.com kcn@norseth.com

9.  Full Copyright

   Copyright (C) The Internet Society (2001).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implmentation may be prepared, copied, published and
   distributed, in whole or in part, without restriction of any kind,
   provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Table of Contents

   1 The SNMP Management Framework ................................    2
   2 Overview .....................................................    3
   2.1 Structure of MIB ...........................................    3
   2.1.1 The dot1dBase Group ......................................    5
   2.1.2 The dot1dStp Group .......................................    5
   2.1.3 The dot1dSr Group ........................................    6
   2.1.4 The dot1dTp Group ........................................    6
   2.1.5 The dot1dStatic Group ....................................    6
   2.2 Relationship to Other MIBs .................................    6
   2.2.1 Relationship to the 'system' group .......................    6
   2.2.2 Relationship to the 'interfaces' group ...................    6
   2.3 Textual Conventions ........................................    7
   3 Definitions ..................................................    7
   4 Security Considerations ......................................   32
   5 Acknowledgments ..............................................   32
   6 References ...................................................   33
   7 Changes from RFC 1493 and Previous Drafts ....................   34
   8 Authors' Addresses ...........................................   34
   9 Full Copyright ...............................................   35