Network Working Group E. Decker

Network Working Group E. Decker
Request for Comments: 1286 cisco Systems, Inc.
P. Langille
Digital Equipment Corporation
A. Rijsinghani
Digital Equipment Corporation
K. McCloghrie
Hughes LAN Systems, Inc.
December 1991

Definitions of Managed Objects for Bridges

Status of this Memo

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

Table of Contents

1. Abstract ............................................. 2
2. The Network Management Framework...................... 2
3. Objects .............................................. 2
3.1 Format of Definitions ............................... 3
4. Overview ............................................. 3
4.1 Structure of MIB .................................... 4
4.1.1 The dot1dBase Group ............................... 7
4.1.2 The dot1dStp Group ................................ 7
4.1.3 The dot1dSr Group ................................. 7
4.1.4 The dot1dTp Group ................................. 7
4.1.5 The dot1dStatic Group ............................. 7
4.2 Relationship to Other MIBs .......................... 7
4.2.1 Relationship to the 'system' group ................ 8
4.2.2 Relationship to the 'interfaces' group ............ 8
4.3 Textual Conventions ................................. 9
5. Definitions .......................................... 9
5.1 Groups in the Bridge MIB ............................ 11
5.2 The dot1dBase Group Definitions ..................... 11
5.3 The dot1dStp Group Definitions ...................... 14
5.4 The dot1dSr Group Definitions ....................... 22
5.5 The dot1dTp Group Definitions ....................... 28
5.6 The dot1dStatic Group Definitions ................... 34
5.8 Traps for use by Bridges ............................ 36
6. Acknowledgments ...................................... 37

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7. References ........................................... 38
8. Security Considerations............................... 39
9. Authors' Addresses.................................... 40

1. 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 bridges based on the
IEEE 802.1d draft standard between Local Area Network (LAN) segments.
Provisions are made for support of transparent and source route
bridging. Provisions are also made so that these objects apply to
bridges connected by subnetworks other than LAN segments.

2. The Network Management Framework

The Internet-standard Network Management Framework consists of three
components. They are:

RFC 1155 which defines the SMI, the mechanisms used for describing
and naming objects for the purpose of management. RFC 1212
defines a more concise description mechanism, which is wholly
consistent with the SMI.

RFC 1156 which defines MIB-I, the core set of managed objects for
the Internet suite of protocols. RFC 1213, defines MIB-II, an
evolution of MIB-I based on implementation experience and new
operational requirements.

RFC 1157 which defines the SNMP, the protocol used for network
access to managed objects.

The Framework permits new objects to be defined for the purpose of
experimentation and evaluation.

3. Objects

Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the subset of Abstract Syntax Notation One (ASN.1) [7]
defined in the SMI. In particular, each object has a name, a syntax,
and an encoding. The name is an object identifier, an
administratively assigned name, which specifies an object type. The
object type together with an object instance serves to uniquely
identify a specific instantiation of the object. For human
convenience, we often use a textual string, termed the OBJECT
DESCRIPTOR, to also refer to the object type.

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The syntax of an object type defines the abstract data structure
corresponding to that object type. The ASN.1 language is used for
this purpose. However, the SMI [3] purposely restricts the ASN.1
constructs which may be used. These restrictions are explicitly made
for simplicity.

The encoding of an object type is simply how that object type is
represented using the object type's syntax. Implicitly tied to the
notion of an object type's syntax and encoding is how the object type
is represented when being transmitted on the network.

The SMI specifies the use of the basic encoding rules of ASN.1 [8],
subject to the additional requirements imposed by the SNMP.

3.1. Format of Definitions

Section 5 contains the specification of all object types contained in
this MIB module. The object types are defined using the conventions
defined in the SMI, as amended by the extensions specified in [9,10].

4. 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 draft IEEE 802.1d specification [11]. Source route
bridging has been defined by I.B.M. and is described in the Token
Ring Architecture Reference [12]. IEEE 802.1d is currently working
on combining the source route and transparent techniques in a
compatible fashion. This memo defines those objects needed for the
management of a bridging entity operating in one of these modes.

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.

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(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.

4.1. 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 [11] 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

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State .SpanningTreeState
Enable
PathCost .PortPathCost
DesignatedRoot .DesignatedRoot
DesignatedCost .DesignatedCost
DesignatedBridge .DesignatedBridge
DesignatedPort .DesignatedPort
ForwardTransitions

dot1dSr
PortTable
Port
HopCount SourceRoutingPort
.PortHopCount
LocalSegment .SegmentNumber
BridgeNum .BridgeNumber
TargetSegment
LargestFrame .LargestFrameSize
STESpanMode .LimitedBroadcastMode
SpecInFrames BridgePort
.ValidSRFramesReceived
SpecOutFrames .ValidSRForwardedOutbound
ApeInFrames
ApeOutFrames .BroadcastFramesForwarded
SteInFrames
SteOutFrames .BroadcastFramesForwarded
SegmentMismatchDiscards .DiscardInvalidRI
DuplicateSegmentDiscards .LanIdMismatch
HopCountExceededDiscards .FramesDiscardedHopCountExceeded
dot1dTp
LearnedEntryDiscards BridgeFilter.DatabaseSize
.NumDynamic,NumStatic
AgingTime BridgeFilter.AgingTime
FdbTable
Address
Status
Port
PortTable
Port
MaxInfo
InFrames BridgePort.FramesReceived
OutFrames .ForwardOutbound
InDiscards .DiscardInbound
dot1dStatic
StaticTable
Address
ReceivePort
AllowedToGoTo

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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 dot1dStpPortNum
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

SourceRoutingPort The Source Routing Supplement,
at the time of this writing,
is not stable. The following
objects were NOT included in
this MIB because they are
redundant or not considered
useful.
.LimitedBroadcastEnable
BridgePort.DupLanIdOrTreeError
.DiscardLackOfBuffers
.DiscardErrorDetails
.DiscardTargetLANInoperable

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.ValidSRDiscardedInbound
.BroadcastBytesForwarded
.NonBroadcastBytesForwarded
.FramesNotReceivedDueToCongestion
.FramesDiscardedDueToInternalError

4.1.1. The dot1dBase Group

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

4.1.2. 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. This group is applicable to any transparent only,
source route, or SRT bridge which implements the Spanning Tree
Protocol.

4.1.3. 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.

4.1.4. 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.

4.1.5. 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.

4.2. 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

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least) the 'system' group and the 'interfaces' group defined in MIB-
II [6].

4.2.1. Relationship to the 'system' group

In MIB-II, 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.

4.2.2. Relationship to the 'interfaces' group

In MIB-II, 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.

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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.

4.3. Textual Conventions

The datatypes, MacAddress, BridgeId and Timeout, are used as textual
conventions in this document. These textual conventions have NO
effect on either the syntax nor the semantics of any managed object.
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.

5. Definitions

RFC1286-MIB DEFINITIONS ::= BEGIN

IMPORTS
Counter, Gauge, TimeTicks
FROM RFC1155-SMI
mib-2
FROM RFC1213-MIB
OBJECT-TYPE
FROM RFC-1212
TRAP-TYPE
FROM RFC-1215;

-- 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 ::= OCTET STRING (SIZE (6)) -- a 6 octet address in
-- the "canonical" order
-- defined by IEEE 802.1a, i.e., as if it were transmitted least
-- significant bit first, even though 802.5 (in contrast to other
-- 802.x protocols) requires MAC addresses to be transmitted most
-- significant bit first.
--
-- 16-bit addresses, if needed, are represented by setting their
-- upper 4 octets to all 0's, i.e., AAFF would be represented
-- as 00000000AAFF.

-- 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:

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BridgeId ::= OCTET STRING (SIZE (8)) -- 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).
-- 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/D9
-- 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 ::= INTEGER -- 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).

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

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-- groups in the Bridge MIB

dot1dBase OBJECT IDENTIFIER ::= { dot1dBridge 1 }

dot1dStp OBJECT IDENTIFIER ::= { dot1dBridge 2 }

dot1dSr OBJECT IDENTIFIER ::= { dot1dBridge 3 }

dot1dTp OBJECT IDENTIFIER ::= { dot1dBridge 4 }

dot1dStatic OBJECT IDENTIFIER ::= { dot1dBridge 5 }

-- the dot1dBase group

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

dot1dBaseBridgeAddress OBJECT-TYPE
SYNTAX MacAddress
ACCESS read-only
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Sections 6.4.1.1.3 and 3.12.5"
::= { dot1dBase 1 }

dot1dBaseNumPorts OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of ports controlled by this bridging
entity."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.4.1.1.3"
::= { dot1dBase 2 }

dot1dBaseType OBJECT-TYPE
SYNTAX INTEGER {

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unknown(1),
transparent-only(2),
sourceroute-only(3),
srt(4)
}
ACCESS read-only
STATUS mandatory
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
ACCESS not-accessible
STATUS mandatory
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
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of information for each port of the
bridge."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.4.2, 6.6.1"
INDEX { dot1dBasePort }
::= { dot1dBasePortTable 1 }

Dot1dBasePortEntry ::=
SEQUENCE {
dot1dBasePort
INTEGER,
dot1dBasePortIfIndex
INTEGER,
dot1dBasePortCircuit
OBJECT IDENTIFIER,
dot1dBasePortDelayExceededDiscards

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Counter,
dot1dBasePortMtuExceededDiscards
Counter
}

dot1dBasePort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The port number of the port for which this entry
contains bridge management information."
::= { dot1dBasePortEntry 1 }

dot1dBasePortIfIndex OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The value of the instance of the ifIndex object,
defined in [4,6], for the interface corresponding
to this port."
::= { dot1dBasePortEntry 2 }

dot1dBasePortCircuit OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
ACCESS read-only
STATUS mandatory
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 Counter
ACCESS read-only
STATUS mandatory

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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
"P802.1d/D9, July 14, 1989: Section 6.6.1.1.3"
::= { dot1dBasePortEntry 4 }

dot1dBasePortMtuExceededDiscards OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 6.6.1.1.3"
::= { dot1dBasePortEntry 5 }

-- the dot1dStp group

-- Implementation of the dot1dStp group is optional. It is
-- implemented by those bridges that support the Spanning Tree
-- Protocol. Transparent, Source Route, and SRT bridges will
-- implement this group only if they support the Spanning Tree
-- Protocol.

dot1dStpProtocolSpecification OBJECT-TYPE
SYNTAX INTEGER {
unknown(1),
decLb100(2),
ieee8021d(3)
}
ACCESS read-only
STATUS mandatory
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."

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::= { dot1dStp 1 }

dot1dStpPriority OBJECT-TYPE
SYNTAX INTEGER (0..65535)
ACCESS read-write
STATUS mandatory
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."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.3.7"
::= { dot1dStp 2 }

dot1dStpTimeSinceTopologyChange OBJECT-TYPE
SYNTAX TimeTicks
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The time (in hundredths of a second) since the
last time a topology change was detected by the
bridge entity."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.8.1.1.3"
::= { dot1dStp 3 }

dot1dStpTopChanges OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The total number of topology changes detected by
this bridge since the management entity was last
reset or initialized."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.8.1.1.3"
::= { dot1dStp 4 }

dot1dStpDesignatedRoot OBJECT-TYPE
SYNTAX BridgeId
ACCESS read-only
STATUS mandatory
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

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the Root Identifier parameter in all Configuration
Bridge PDUs originated by this node."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.3.1"
::= { dot1dStp 5 }

dot1dStpRootCost OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The cost of the path to the root as seen from
this bridge."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.3.2"
::= { dot1dStp 6 }

dot1dStpRootPort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The port number of the port which offers the
lowest cost path from this bridge to the root
bridge."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.3.3"
::= { dot1dStp 7 }

dot1dStpMaxAge OBJECT-TYPE
SYNTAX Timeout
ACCESS read-only
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 4.5.3.4"
::= { dot1dStp 8 }

dot1dStpHelloTime OBJECT-TYPE
SYNTAX Timeout
ACCESS read-only
STATUS mandatory
DESCRIPTION

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"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
"P802.1d/D9, July 14, 1989: Section 4.5.3.5"
::= { dot1dStp 9 }

dot1dStpHoldTime OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 4.5.3.14"
::= { dot1dStp 10 }

dot1dStpForwardDelay OBJECT-TYPE
SYNTAX Timeout
ACCESS read-only
STATUS mandatory
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 a particular state before moving to the
next state. For example, how long a port stays in
the Listening state when moving from Blocking to
Learning. 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
"P802.1d/D9, July 14, 1989: Section 4.5.3.6"
::= { dot1dStp 11 }

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dot1dStpBridgeMaxAge OBJECT-TYPE
SYNTAX Timeout (600..4000)
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The value that all bridges use for MaxAge when
this bridge is acting as the root. Note that
802.1d/D9 specifies that the range for this
parameter is related to the value of
dot1dStpBridgeHelloTime. The granularity of this
timer is specified by 802.1d/D9 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
"P802.1d/D9, July 14, 1989: Section 4.5.3.8"
::= { dot1dStp 12 }

dot1dStpBridgeHelloTime OBJECT-TYPE
SYNTAX Timeout (100..1000)
ACCESS read-write
STATUS mandatory
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/D9 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
"P802.1d/D9, July 14, 1989: Section 4.5.3.9"
::= { dot1dStp 13 }

dot1dStpBridgeForwardDelay OBJECT-TYPE
SYNTAX Timeout (400..3000)
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The value that all bridges use for ForwardDelay
when this bridge is acting as the root. Note that
802.1d/D9 specifies that the range for this
parameter is related to the value of
dot1dStpBridgeMaxAge. The granularity of this
timer is specified by 802.1d/D9 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

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RFC 1286 Bridge MIB December 1991

"P802.1d/D9, July 14, 1989: Section 4.5.3.10"
::= { dot1dStp 14 }

-- The Spanning Tree Port Table

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

dot1dStpPortEntry OBJECT-TYPE
SYNTAX Dot1dStpPortEntry
ACCESS not-accessible
STATUS mandatory
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
INTEGER,
dot1dStpPortPriority
INTEGER,
dot1dStpPortState
INTEGER,
dot1dStpPortEnable
INTEGER,
dot1dStpPortPathCost
INTEGER,
dot1dStpPortDesignatedRoot
BridgeId,
dot1dStpPortDesignatedCost
INTEGER,
dot1dStpPortDesignatedBridge
BridgeId,
dot1dStpPortDesignatedPort
OCTET STRING,
dot1dStpPortForwardTransitions
Counter

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}

dot1dStpPort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The port number of the port for which this entry
contains Spanning Tree Protocol management
information."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.8.2.1.2"
::= { dot1dStpPortEntry 1 }

dot1dStpPortPriority OBJECT-TYPE
SYNTAX INTEGER (0..255)
ACCESS read-write
STATUS mandatory
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."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.1"
::= { dot1dStpPortEntry 2 }

dot1dStpPortState OBJECT-TYPE
SYNTAX INTEGER {
disabled(1),
blocking(2),
listening(3),
learning(4),
forwarding(5),
broken(6)
}
ACCESS read-only
STATUS mandatory
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)."

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REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.2"
::= { dot1dStpPortEntry 3 }

dot1dStpPortEnable OBJECT-TYPE
SYNTAX INTEGER {
enabled(1),
disabled(2)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The enabled/disabled status of the port."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.2"
::= { dot1dStpPortEntry 4 }

dot1dStpPortPathCost OBJECT-TYPE
SYNTAX INTEGER (1..65535)
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The contribution of this port to the path cost of
paths towards the spanning tree root which include
this port."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.3"
::= { dot1dStpPortEntry 5 }

dot1dStpPortDesignatedRoot OBJECT-TYPE
SYNTAX BridgeId
ACCESS read-only
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 4.5.5.4"
::= { dot1dStpPortEntry 6 }

dot1dStpPortDesignatedCost OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The path cost of the Designated Port of the

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segment connected to this port. This value is
compared to the Root Path Cost field in received
bridge PDUs."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.5"
::= { dot1dStpPortEntry 7 }

dot1dStpPortDesignatedBridge OBJECT-TYPE
SYNTAX BridgeId
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The Bridge Identifier of the bridge which this
port considers to be the Designated Bridge for
this port's segment."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.6"
::= { dot1dStpPortEntry 8 }

dot1dStpPortDesignatedPort OBJECT-TYPE
SYNTAX OCTET STRING (SIZE (2))
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The Port Identifier of the port on the Designated
Bridge for this port's segment."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 4.5.5.7"
::= { dot1dStpPortEntry 9 }

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

-- the dot1dSr group

-- Implementation of the dot1dSr group is optional. It is
-- implemented by those bridges that support the source route
-- bridging mode, including Source Route and SRT bridges.

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dot1dSrPortTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dot1dSrPortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A table that contains information about every
port that is associated with this source route
bridge."
::= { dot1dSr 1 }

dot1dSrPortEntry OBJECT-TYPE
SYNTAX Dot1dSrPortEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A list of information for each port of a source
route bridge."
INDEX { dot1dSrPort }
::= { dot1dSrPortTable 1 }

Dot1dSrPortEntry ::=
SEQUENCE {
dot1dSrPort
INTEGER,
dot1dSrPortHopCount
INTEGER,
dot1dSrPortLocalSegment
INTEGER,
dot1dSrPortBridgeNum
INTEGER,
dot1dSrPortTargetSegment
INTEGER,
dot1dSrPortLargestFrame
INTEGER,
dot1dSrPortSTESpanMode
INTEGER,
dot1dSrPortSpecInFrames
Counter,
dot1dSrPortSpecOutFrames
Counter,
dot1dSrPortApeInFrames
Counter,
dot1dSrPortApeOutFrames
Counter,
dot1dSrPortSteInFrames
Counter,
dot1dSrPortSteOutFrames
Counter,

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dot1dSrPortSegmentMismatchDiscards
Counter,
dot1dSrPortDuplicateSegmentDiscards
Counter,
dot1dSrPortHopCountExceededDiscards
Counter
}

dot1dSrPort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The port number of the port for which this entry
contains Source Route management information."
::= { dot1dSrPortEntry 1 }

dot1dSrPortHopCount OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The maximum number of routing descriptors allowed
in an All Paths or Spanning Tree Explorer frames."
::= { dot1dSrPortEntry 2 }

dot1dSrPortLocalSegment OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The segment number that uniquely identifies the
segment to which this port is connected. Current
source routing protocols limit this value to the
range: 0 through 4095. A value of 65535 signifies
that no segment number is assigned to this port."
::= { dot1dSrPortEntry 3 }

dot1dSrPortBridgeNum OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"A bridge number uniquely identifies a bridge when
more than one bridge is used to span the same two
segments. Current source routing protocols limit
this value to the range: 0 through 15. A value of
65535 signifies that no bridge number is assigned

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to this bridge."
::= { dot1dSrPortEntry 4 }

dot1dSrPortTargetSegment OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The segment number that corresponds to the target
segment this port is considered to be connected to
by the bridge. Current source routing protocols
limit this value to the range: 0 through 4095. A
value of 65535 signifies that no target segment is
assigned to this port."
::= { dot1dSrPortEntry 5 }

-- It would be nice if we could use ifMtu as the size of the
-- largest frame, 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).

dot1dSrPortLargestFrame OBJECT-TYPE
SYNTAX INTEGER {
dot1dSrMtu516 (516),
dot1dSrMtu1500 (1500),
dot1dSrMtu2052 (2052),
dot1dSrMtu4472 (4472),
dot1dSrMtu8144 (8144),
dot1dSrMtu11407 (11407), -- yes this is correct don't
dot1dSrMtu17800 (17800), -- ask me where it came from.
dot1dSrMtu65535 (65535)
}

ACCESS read-write
STATUS mandatory
DESCRIPTION
"The maximum size of the INFO field (LLC and
above) that this port can send/receive. It does
not include any MAC level (framing) octets. The
value of this object is used by this bridge to
determine whether a modification of the
LargestFrame (LF, see [14]) field of the Routing
Control field of the Routing Information Field is
necessary. Valid values as defined by the 802.5
source routing bridging specification[14] are 516,
1500, 2052, 4472, 8144, 11407, 17800, and 65535
octets. Behavior of the port when an illegal

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value is written is implementation specific. It
is recommended that a reasonable legal value be
chosen."
::= { dot1dSrPortEntry 6 }

dot1dSrPortSTESpanMode OBJECT-TYPE
SYNTAX INTEGER {
auto-span(1),
disabled(2),
forced(3)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"Determines how this port behaves when presented
with a Spanning Tree Explorer frame. The value
'disabled(2)' indicates that the port will not
accept or send Spanning Tree Explorer packets; any
STE packets received will be silently discarded.
The value 'forced(3)' indicates the port will
always accept and propagate Spanning Tree Explorer
frames. This allows a manually configured
Spanning Tree for this class of packet to be
configured. Note that unlike transparent bridging
this is not catastrophic to the network if there
are loops. The value 'auto-span(1)' can only be
returned by a bridge that both implements the
Spanning Tree Protocol and has use of the protocol
enabled on this port. The behavior of the port for
Spanning Tree Explorer frames is determined by the
state of dot1dStpPortState. If the port is in the
'forwarding' state, the frame will be accepted or
propagated. Otherwise it will be silently
discarded."
::= { dot1dSrPortEntry 7 }

dot1dSrPortSpecInFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of specifically routed frames that
have been received from this port's segment."
::= { dot1dSrPortEntry 8 }

dot1dSrPortSpecOutFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only

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STATUS mandatory
DESCRIPTION
"The number of specifically routed frames that
this port has transmitted on its segment."
::= { dot1dSrPortEntry 9 }

dot1dSrPortApeInFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of all paths explorer frames that have
been received by this port from its segment."
::= { dot1dSrPortEntry 10 }

dot1dSrPortApeOutFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of all paths explorer frames that have
been transmitted by this port on its segment."
::= { dot1dSrPortEntry 11 }

dot1dSrPortSteInFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of spanning tree explorer frames that
have been received by this port from its segment."
::= { dot1dSrPortEntry 12 }

dot1dSrPortSteOutFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of spanning tree explorer frames that
have been transmitted by this port on its
segment."
::= { dot1dSrPortEntry 13 }

dot1dSrPortSegmentMismatchDiscards OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION

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"The number of explorer frames that have been
discarded by this port because the routing
descriptor field contained an invalid adjacent
segment value."
::= { dot1dSrPortEntry 14 }

dot1dSrPortDuplicateSegmentDiscards OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of frames that have been discarded by
this port because the routing descriptor field
contained a duplicate segment identifier."
::= { dot1dSrPortEntry 15 }

dot1dSrPortHopCountExceededDiscards OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"The number of explorer frames that have been
discarded by this port because the Routing
Information Field has exceeded the maximum route
descriptor length."
::= { dot1dSrPortEntry 16 }

-- 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 Counter
ACCESS read-only
STATUS mandatory
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

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RFC 1286 Bridge MIB December 1991

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
"P802.1d/D9, July 14, 1989: Section 6.7.1.1.3"
::= { dot1dTp 1 }

dot1dTpAgingTime OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
DESCRIPTION
"The timeout period in seconds for aging out
dynamically learned forwarding information."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.7.1.1.3"
::= { dot1dTp 2 }

-- The Forwarding Database for Transparent Bridges

dot1dTpFdbTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dot1dTpFdbEntry
ACCESS not-accessible
STATUS mandatory
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
ACCESS not-accessible
STATUS mandatory
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

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RFC 1286 Bridge MIB December 1991

MacAddress,
dot1dTpFdbPort
INTEGER,
dot1dTpFdbStatus
INTEGER
}

dot1dTpFdbAddress OBJECT-TYPE
SYNTAX MacAddress
ACCESS read-only
STATUS mandatory
DESCRIPTION
"A unicast MAC address for which the bridge has
forwarding and/or filtering information."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 3.9.1, 3.9.2"
::= { dot1dTpFdbEntry 1 }

dot1dTpFdbPort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
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)
}
ACCESS read-only
STATUS mandatory

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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
ACCESS not-accessible
STATUS mandatory
DESCRIPTION
"A table that contains information about every
port that is associated with this transparent

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RFC 1286 Bridge MIB December 1991

bridge."
::= { dot1dTp 4 }

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

Dot1dTpPortEntry ::=
SEQUENCE {
dot1dTpPort
INTEGER,
dot1dTpPortMaxInfo
INTEGER,
dot1dTpPortInFrames
Counter,
dot1dTpPortOutFrames
Counter,
dot1dTpPortInDiscards
Counter
}

dot1dTpPort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-only
STATUS mandatory
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 INTEGER
ACCESS read-only
STATUS mandatory
DESCRIPTION

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"The maximum size of the INFO (non-MAC) field that
this port will receive or transmit."
::= { dot1dTpPortEntry 2 }

dot1dTpPortInFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
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."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.6.1.1.3"
::= { dot1dTpPortEntry 3 }

dot1dTpPortOutFrames OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
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."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.6.1.1.3"
::= { dot1dTpPortEntry 4 }

dot1dTpPortInDiscards OBJECT-TYPE
SYNTAX Counter
ACCESS read-only
STATUS mandatory
DESCRIPTION
"Count of valid frames received which were
discarded (i.e., filtered) by the Forwarding
Process."
REFERENCE
"P802.1d/D9, July 14, 1989: Section 6.6.1.1.3"
::= { dot1dTpPortEntry 5 }

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-- The Static (Destination-Address Filtering) Database

-- Implementation of this group is optional.

dot1dStaticTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dot1dStaticEntry
ACCESS not-accessible
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 6.7.2"
::= { dot1dStatic 1 }

dot1dStaticEntry OBJECT-TYPE
SYNTAX Dot1dStaticEntry
ACCESS not-accessible
STATUS mandatory
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
"P802.1d/D9, July 14,1989: Section 6.7.2"
INDEX { dot1dStaticAddress, dot1dStaticReceivePort }
::= { dot1dStaticTable 1 }

Dot1dStaticEntry ::=
SEQUENCE {
dot1dStaticAddress
MacAddress,
dot1dStaticReceivePort
INTEGER,
dot1dStaticAllowedToGoTo

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RFC 1286 Bridge MIB December 1991

OCTET STRING,
dot1dStaticStatus
INTEGER
}

dot1dStaticAddress OBJECT-TYPE
SYNTAX MacAddress
ACCESS read-write
STATUS mandatory
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
"P802.1d/D9, July 14, 1989: Section 3.9.1, 3.9.2"
::= { dot1dStaticEntry 1 }

dot1dStaticReceivePort OBJECT-TYPE
SYNTAX INTEGER
ACCESS read-write
STATUS mandatory
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
ACCESS read-write
STATUS mandatory
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

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RFC 1286 Bridge MIB December 1991

'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.)"
::= { dot1dStaticEntry 3 }

dot1dStaticStatus OBJECT-TYPE
SYNTAX INTEGER {
other(1),
invalid(2),
permanent(3),
deleteOnReset(4),
deleteOnTimeout(5)
}
ACCESS read-write
STATUS mandatory
DESCRIPTION
"This object indicates the status of this entry.
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 }

-- Traps for use by Bridges

-- Traps for the Spanning Tree Protocol

newRoot TRAP-TYPE
ENTERPRISE dot1dBridge
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

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RFC 1286 Bridge MIB December 1991

its election."
::= 1

topologyChange TRAP-TYPE
ENTERPRISE dot1dBridge
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."
::= 2

END

6. Acknowledgments

This document was produced on behalf of the Bridge Sub-Working Group
of the SNMP Working Group of the Internet Engineering Task Force.
Over the course of its deliberations, the working group received four
separate documents for consideration as the basis for its work. The
first was submitted by Stan Froyd of Advanced Computer
Communications; the second by Richard Fox of SynOptics; the third by
Eric Decker of cisco Inc. and Keith McCloghrie of Hughes LAN Systems;
and the fourth by Paul Langille and Anil Rijsinghani of Digital
Equipment Corp. After considering the submissions, the working group
chose to proceed with a document formed as a conjunction of the
latter two submissions. This document is the result.

The authors wish to thank the members of the Bridge Working Group for
their many comments and suggestions which improved this effort. In
particular, Fred Baker (chairman of the working group) of ACC, Steve
Sherry of Xyplex, and Frank Kastenholz of Clearpoint Research Corp.
Others members of the Bridge Working Group who contributed to this
effort are:

Bill Anderson, Mitre
Karl Auerbach, Epilogue
Fred Baker, ACC (chair)
Terry Bradley, Wellfleet
Ted Brunner, Bellcore
Jeffrey Buffum, Apollo
Chris ChioTasso, Fibronics
Anthony Chung, HLS
Chuck Davin, MIT-LCS
Andy Davis, Spider
Eric Decker, cisco

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RFC 1286 Bridge MIB December 1991

Nadya El-Afandi, Network Systems
Gary Ellis,HP/Apollo
Richard Fox, SynOptics
Stan Froyd, ACC
Frank Kastenholz, Clearpoint Research
Shirnshon Kaufman,
Jim Kinder, Fibercom
Cheryl Krupczak,NCR
Paul Langille, Digital
Peter Lin,Vitalink
Keith McCloghrie, HLS
Donna McMaster, SynOptics
Dave Perkins, 3Com
Jim Reinstedler, Ungermann Bass
Anil Rijsinghani, Digital
Mark Schaefer, David Systems
Steve Sherry, Xyplex
Bob Stewart, Xyplex
Emil Sturniolo,
Kevin Synott, Retix
Ian Thomas, Chipcom
Maurice Turcott, Racal
Fei Xu,

7. References

[1] Cerf, V., "IAB Recommendations for the Development of Internet
Network Management Standards", RFC 1052, NRI, April 1988.

[2] Cerf, V., "Report of the Second Ad Hoc Network Management Review
Group", RFC 1109, NRI, August 1989.

[3] Rose M., and K. McCloghrie, "Structure and Identification of
Management Information for TCP/IP-based internets", RFC 1155,
Performance Systems International, Hughes LAN Systems, May 1990.

[4] McCloghrie K., and M. Rose, "Management Information Base for
Network Management of TCP/IP-based internets", RFC 1156, Hughes
LAN Systems, Performance Systems International, May 1990.

[5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
Network Management Protocol", RFC 1157, SNMP Research,
Performance Systems International, Performance Systems
International, MIT Laboratory for Computer Science, May 1990.

[6] McCloghrie K., and M. Rose, Editors, "Management Information Base
for Network Management of TCP/IP-based internets", RFC 1213,
Performance Systems International, March 1991.

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RFC 1286 Bridge MIB December 1991

[7] Information processing systems - Open Systems Interconnection -
Specification of Abstract Syntax Notation One (ASN.1),
International Organization for Standardization, International
Standard 8824, December 1987.

[8] Information processing systems - Open Systems Interconnection -
Specification of Basic Encoding Rules for Abstract Notation One
(ASN.1), International Organization for Standardization,
International Standard 8825, December 1987.

[9] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
RFC 1212, Performance Systems International, Hughes LAN Systems,
March 1991.

[10] Rose, M., Editor, "A Convention for Defining Traps for use with
the SNMP", RFC 1215, Performance Systems International, March
1991.

[11] ANSI/IEEE Draft P802.1d/D9 MAC Bridges, "IEEE Project 802 Local
and Metropolitan Area Networks", July 14, 1989.

[12] I.B.M. Token Ring Architecture Reference.

[13] ISO DIS 10038 MAC Bridges.

[14] ANSI/IEEE P802.1x/P802.5x, "Proposed Draft Local Area Network
Standard -- MAC Bridges, Source Routing Supplement", IEEE Project
802, September 1990.

[15] ANSI/IEEE 802.1y, "Source Routing Tutorial for End System
Operation", September 1990.

8. Security Considerations

Security issues are not discussed in this memo.

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RFC 1286 Bridge MIB December 1991

9. Authors' Addresses

Eric B. Decker
cisco Systems, Inc.
1525 O'Brien Dr.
Menlo Park, CA 94025

Phone: (415) 326-1941
Email: [email protected]

Paul Langille
Digital Equipment Corporation
Digital Drive, MK02-2/K03
Merrimack, NH 03054

Phone: (603) 884-4045
EMail: [email protected]

Anil Rijsinghani
Digital Equipment Corporation
153 Taylor St.
Littleton, MA 01460

Phone: (508)952-3520
EMail: [email protected]

Keith McCloghrie
Hughes LAN Systems
1225 Charleston Road
Mountain View, CA 94043

Phone: (415) 966-7934
EMail: [email protected]

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