Network Working Group                                    J. Cook, Editor
Request for Comments: 1284                           Chipcom Corporation
                                                          December 1991


                    Definitions of Managed Objects
                for the Ethernet-like Interface Types

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...............................................    1
  2. The Network Management Framework.......................    1
  3. Objects ...............................................    2
  3.1 Format of Definitions ................................    2
  4. Overview ..............................................    3
  5. Definitions ...........................................    4
  5.1 The Generic Ethernet-like Group ......................    4
  5.2 The Ethernet-Like Statistics Group ...................    9
  5.3 The Ethernet-like Collision Statistics Group .........   16
  5.4 802.3 Tests ..........................................   17
  5.5 802.3 Hardware Chipsets ..............................   18
  6. Acknowledgements ......................................   19
  7. References ............................................   19
  Security Considerations...................................   21
  Author's Address..........................................   21

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 ethernet-like objects.

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



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     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.

  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 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 [13].




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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


4.  Overview

  Instances of these object types represent attributes of an interface
  to an ethernet-like communications medium.  At present, ethernet-like
  media are identified by three values of the ifType object in the
  Internet-standard MIB:

              ethernet-csmacd(6)
              iso88023-csmacd(7)
              starLan(11)

  For these interfaces, the value of the ifSpecific variable in the
  MIB-II [6] has the OBJECT IDENTIFIER value:

              dot3    OBJECT IDENTIFER ::= { transmission 7 }

  The definitions presented here are based on the IEEE 802.3 Layer
  Management Specification [9], as originally interpreted by Frank
  Kastenholz of Interlan in [10].  Implementors of these MIB objects
  should note that the IEEE document explicitly describes (in the form
  of Pascal pseudocode) when, where, and how various MAC attributes are
  measured.  The IEEE document also describes the effects of MAC
  actions that may be invoked by manipulating instances of the MIB
  objects defined here.

  To the extent that some of the attributes defined in [9] are
  represented by previously defined objects in the Internet-standard
  MIB or in the generic interface extensions MIB [11], such attributes
  are not redundantly represented by objects defined in this memo.
  Among the attributes represented by objects defined in other memos
  are the number of octets transmitted or received on a particular
  interface, the number of frames transmitted or received on a
  particular interface, the promiscuous status of an interface, the MAC
  address of an interface, and multicast information associated with an
  interface.

  The relationship between an ethernet-like interface and an interface
  in the context of the Internet-standard MIB is one-to-one.  As such,
  the value of an ifIndex object instance can be directly used to
  identify corresponding instances of the objects defined herein.











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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


5.  Definitions


   RFC1284-MIB DEFINITIONS ::= BEGIN

   IMPORTS
           Counter, Gauge
                   FROM RFC1155-SMI
           transmission
                   FROM RFC1213-MIB
           OBJECT-TYPE
                   FROM RFC-1212;

   --  This MIB module uses the extended OBJECT-TYPE macro as
   --  defined in [13]


   --  this is the MIB module for ethernet-like objects

   dot3    OBJECT IDENTIFIER ::= { transmission 7 }


   -- the Generic Ethernet-like group

   -- Implementation of this group is mandatory for all systems
   -- that attach to an ethernet-like medium.

   dot3Table OBJECT-TYPE
       SYNTAX  SEQUENCE OF Dot3Entry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "Status information and control variables for a
               collection of ethernet-like interfaces attached to
               a particular system."
       ::= { dot3 1 }

   dot3Entry OBJECT-TYPE
       SYNTAX  Dot3Entry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "Status information and control variables for a
               particular interface to an ethernet-like medium."
       INDEX   { dot3Index }
       ::= { dot3Table 1 }





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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


   Dot3Entry ::=
       SEQUENCE {
           dot3Index
               INTEGER,
           dot3InitializeMac
               INTEGER,
           dot3MacSubLayerStatus
               INTEGER,
           dot3MulticastReceiveStatus
               INTEGER,
           dot3TxEnabled
               INTEGER,
           dot3TestTdrValue
               Gauge
      }

   dot3Index OBJECT-TYPE
       SYNTAX  INTEGER
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "An index value that uniquely identifies an
               interface to an ethernet-like medium.  The
               interface identified by a particular value of this
               index is the same interface as identified by the
               same value of ifIndex."
       ::= { dot3Entry 1 }

   dot3InitializeMac OBJECT-TYPE
       SYNTAX  INTEGER { initialized(1), uninitialized(2) }
       ACCESS  read-write
       STATUS  mandatory
       DESCRIPTION
               "The initialization status of the MAC and PLS
               (Physical Layer Signalling) subsystems for a
               particular interface. The value initialized(1)
               signifies that the subsystems for a particular
               interface have been previously initialized; the
               value uninitialized(2) signifies that they have
               not been previously initialized.

               Each alteration of an instance of this object to
               either of the values initialized(1) or
               uninitialized(2) is analogous to an invocation of
               the initializeMAC action defined in [9] and has
               the effect of (re-)initializing the MAC and PLS
               subsystems for the associated interface. In
               particular,



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                    all management counters pertaining to the MAC
                    and PLS subsystems for said interface are
                    reset to zero;

                    the receive and transmit layer management
                    state variables (receiveEnabled and
                    transmitEnabled in [9]) are set to enable
                    reception and transmission of frames;

                    the promiscuous receive function is disabled;
                    and

                    multicast reception is disabled."
       ::= { dot3Entry 2 }

   dot3MacSubLayerStatus OBJECT-TYPE
       SYNTAX  INTEGER { enabled(1), disabled(2) }
       ACCESS  read-write
       STATUS  mandatory
       DESCRIPTION
               "The operational status of the MAC sublayer for a
               particular interface.  The value enabled(1)
               signifies that the MAC sublayer for said interface
               is operational for both transmitting and receiving
               frames -- that is, that the value of both the
               receive and transmit layer management state
               variables (receiveEnabled and transmitEnabled in
               [9]) for said interface are true.  The value
               disabled(2) signifies that the MAC sublayer for
               said interface is not operational for either
               transmitting or receiving frames. In particular,
               the value of an instance of this object is
               disabled(2) whenever the value of the
               corresponding instance of the dot3Enabled object
               is false(2).

               Each alteration of an instance of this object to
               the value enabled(1) is analogous to an invocation
               of the enableMACSublayer action defined in [9] and
               has the effect of starting normal transmit and
               receive operations (from the ``idle'' state) on
               the associated interface. In particular, such an
               alteration has the effect of resetting the PLS for
               said interface and of setting the receive and
               transmit layer management state variables
               (receiveEnabled and transmitEnabled in [9]) to be
               true.




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               Each alteration of an instance of this object to
               the value disabled(2) is analogous to an
               invocation of the disableMACSublayer action
               defined in [9] and has the effect of terminating
               transmit and receive operations on the associated
               interface. In particular, such an alteration has
               the effect of setting the receive and transmit
               layer management state variables (receiveEnabled
               and transmitEnabled in [9]) to be false. Any
               transmissions/receptions in progress are completed
               before operation is terminated."
       ::= { dot3Entry 3 }

   dot3MulticastReceiveStatus OBJECT-TYPE
       SYNTAX  INTEGER { enabled(1), disabled(2) }
       ACCESS  read-write
       STATUS  mandatory
       DESCRIPTION
               "The multicast receive status for a particular
               interface.  The value enabled(1) signifies that
               reception of multicast frames by the MAC sublayer
               is enabled on said interface. The value
               disabled(2) signifies that reception of multicast
               frames by the MAC sublayer is not enabled on said
               interface.

               Each alteration of an instance of this object to
               the value enabled(1) is analogous to an invocation
               of the enableMulticastReceive action defined in
               [9] and has the effect of enabling multicast frame
               reception on the associated interface. Actual
               reception of multicast frames is only possible on
               an interface when the values for the associated
               instances of the dot3MulticastReceiveStatus and
               dot3MacSubLayerStatus objects are enabled(1) and
               enabled(1), respectively.

               Each alteration of an instance of this object to
               the value disabled(2) is analogous to an
               invocation of the disableMulticastReceive action
               defined in [9] and has the effect of inhibiting
               multicast frame reception on the associated
               interface."
       ::= { dot3Entry 4 }

   dot3TxEnabled OBJECT-TYPE
       SYNTAX  INTEGER { true(1), false(2)  }
       ACCESS  read-write



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       STATUS  mandatory
       DESCRIPTION
               "The transmit layer management state variable
               (transmitEnabled as defined in [9]) for a
               particular interface.  The value true(1) signifies
               that the MAC frame transmission is enabled on said
               interface. The value false(2) signifies that the
               MAC frame transmission is inhibited on said
               interface. In particular, the value of an instance
               of this object is false(2) whenever the value of
               the corresponding instance of the
               dot3MacSubLayerStatus object is disabled(2).

               Each alteration of an instance of this object to
               the value true(1) is analogous to an invocation of
               the enableTransmit action defined in [9] and has
               the effect of enabling MAC sublayer frame
               transmission on the associated interface. In
               particular, such an alteration has the effect of
               setting the transmit layer management state
               variable (transmitEnabled in [9]) for said
               interface to be true.

               Each alteration of an instance of this object to
               the value false(2) is analogous to an invocation
               of the disableTransmit action defined in [9] and
               has the effect of inhibiting MAC sublayer frame
               transmission on the associated interface. In
               particular, such an alteration has the effect of
               setting the transmit layer management state
               variable (transmitEnabled in [9]) for said
               interface to be false. Any transmissions in
               progress are completed before transmission is
               inhibited."
       ::= { dot3Entry 5 }

   dot3TestTdrValue OBJECT-TYPE
       SYNTAX  Gauge
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
              "The number of 10 MHz ticks which elapsed between
              the beginning of a TDR measurement and the
              collision which ended it, for the most recently
              executed TDR test.  If no TDR test has been
              executed, or the last TDR value is not available,
             this object has the value 0."
       ::= { dot3Entry 6 }



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


   -- the Ethernet-like Statistics group

   -- Implementation of this group is mandatory

   -- Due to implementation restrictions (e.g. in the
   -- instrumentation provided by a chipset, or a device
   -- driver), some of the counters in this group may be
   -- difficult or impossible to implement.
   -- In such cases, an implementator should apply reasonable
   -- best effort to detect as many occurrences as possible.
   -- In any case, the value of a counter will be the number
   -- actually detected, which will always be less or equal
   -- to the number of actual occurrences.  In the extreme
   -- case of a total inability to detect occurrences, the
   -- counter will always be zero.

   -- Vendors are strongly encouraged to document in user guides and
   -- other appropriate documentation the conditions under which the
   -- values of the counters in this group may represent an
   -- underestimate of the true count.

   dot3StatsTable OBJECT-TYPE
       SYNTAX  SEQUENCE OF Dot3StatsEntry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "Statistics for a collection of ethernet-like
               interfaces attached to a particular system."
       ::= { dot3 2 }

   dot3StatsEntry OBJECT-TYPE
       SYNTAX  Dot3StatsEntry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "Statistics for a particular interface to an
               ethernet-like medium."
       INDEX   { dot3StatsIndex }
       ::= { dot3StatsTable 1 }

   Dot3StatsEntry ::=
       SEQUENCE {
           dot3StatsIndex
               INTEGER,
           dot3StatsAlignmentErrors
               Counter,
           dot3StatsFCSErrors
               Counter,



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


           dot3StatsSingleCollisionFrames
               Counter,
           dot3StatsMultipleCollisionFrames
               Counter,
           dot3StatsSQETestErrors
               Counter,
           dot3StatsDeferredTransmissions
               Counter,
           dot3StatsLateCollisions
               Counter,
           dot3StatsExcessiveCollisions
               Counter,
           dot3StatsInternalMacTransmitErrors
               Counter,
           dot3StatsCarrierSenseErrors
               Counter,
           dot3StatsExcessiveDeferrals
               Counter,
           dot3StatsFrameTooLongs
               Counter,
           dot3StatsInRangeLengthErrors
               Counter,
           dot3StatsOutOfRangeLengthFields
               Counter,
           dot3StatsInternalMacReceiveErrors
               Counter
       }

   dot3StatsIndex OBJECT-TYPE
       SYNTAX  INTEGER
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "An index value that uniquely identifies an
               interface to an ethernet-like medium.  The
               interface identified by a particular value of this
               index is the same interface as identified by the
               same value of ifIndex."
       ::= { dot3StatsEntry 1 }

   dot3StatsAlignmentErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames received on a particular
               interface that are not an integral number of
               octets in length and do not pass the FCS check.



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               The count represented by an instance of this
               object is incremented when the alignmentError
               status is returned by the MAC service to the LLC
               (or other MAC user). Received frames for which
               multiple error conditions obtain are, according to
               the conventions of [9], counted exclusively
               according to the error status presented to the
               LLC."
       ::= { dot3StatsEntry 2 }

   dot3StatsFCSErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames received on a particular
               interface that are an integral number of octets in
               length but do not pass the FCS check.

               The count represented by an instance of this
               object is incremented when the frameCheckError
               status is returned by the MAC service to the LLC
               (or other MAC user). Received frames for which
               multiple error conditions obtain are, according to
               the conventions of [9], counted exclusively
               according to the error status presented to the
               LLC."
       ::= { dot3StatsEntry 3 }

   dot3StatsSingleCollisionFrames OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of successfully transmitted frames on a
               particular interface for which transmission is
               inhibited by exactly one collision.

               A frame that is counted by an instance of this
               object is also counted by the corresponding
               instance of either the ifOutUcastPkts or
               ifOutNUcastPkts object and is not counted by the
               corresponding instance of the
               dot3StatsMultipleCollisionFrames object."
      ::= { dot3StatsEntry 4 }






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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


   dot3StatsMultipleCollisionFrames OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of successfully transmitted frames on a
               particular interface for which transmission is
               inhibited by more than one collision.

               A frame that is counted by an instance of this
               object is also counted by the corresponding
               instance of either the ifOutUcastPkts or
               ifOutNUcastPkts object and is not counted by the
               corresponding instance of the
               dot3StatsSingleCollisionFrames object."
       ::= { dot3StatsEntry 5 }

   dot3StatsSQETestErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of times that the SQE TEST ERROR message
               is generated by the PLS sublayer for a particular
               interface. The SQE TEST ERROR message is defined
               in section 7.2.2.2.4 of [12] and its generation is
               described in section 7.2.4.6 of the same
               document."
       ::= { dot3StatsEntry 6 }

   dot3StatsDeferredTransmissions OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames for which the first
               transmission attempt on a particular interface is
               delayed because the medium is busy.

               The count represented by an instance of this
               object does not include frames involved in
               collisions."
       ::= { dot3StatsEntry 7 }

   dot3StatsLateCollisions OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory



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       DESCRIPTION
               "The number of times that a collision is detected
               on a particular interface later than 512 bit-times
               into the transmission of a packet.

               Five hundred and twelve bit-times corresponds to
               51.2 microseconds on a 10 Mbit/s system. A (late)
               collision included in a count represented by an
               instance of this object is also considered as a
               (generic) collision for purposes of other
               collision-related statistics."
       ::= { dot3StatsEntry 8 }

   dot3StatsExcessiveCollisions OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames for which transmission on a
               particular interface fails due to excessive
               collisions."
       ::= { dot3StatsEntry 9 }

   dot3StatsInternalMacTransmitErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames for which transmission on a
               particular interface fails due to an internal MAC
               sublayer transmit error. A frame is only counted
               by an instance of this object if it is not counted
               by the corresponding instance of either the
               dot3StatsLateCollisions object, the
               dot3StatsExcessiveCollisions object, the
               dot3StatsCarrierSenseErrors object, or the
               dot3StatsExcessiveDeferrals object.

               The precise meaning of the count represented by an
               instance of this object is implementation-
               specific.  In particular, an instance of this
               object may represent a count of transmission
               errors on a particular interface that are not
               otherwise counted."
       ::= { dot3StatsEntry 10 }






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   dot3StatsCarrierSenseErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "The number of times that the carrier sense
               condition was lost or never asserted when
               attempting to transmit a frame on a particular
               interface.

               The count represented by an instance of this
               object is incremented at most once per
               transmission attempt, even if the carrier sense
               condition fluctuates during a transmission
               attempt."
       ::= { dot3StatsEntry 11 }

   dot3StatsExcessiveDeferrals OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames for which transmission on a
               particular interface is deferred for an excessive
               period of time."
       ::= { dot3StatsEntry 12 }

   dot3StatsFrameTooLongs OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames received on a particular
               interface that exceed the maximum permitted frame
               size.

               The count represented by an instance of this
               object is incremented when the frameTooLong status
               is returned by the MAC service to the LLC (or
               other MAC user). Received frames for which
               multiple error conditions obtain are, according to
               the conventions of [9], counted exclusively
               according to the error status presented to the
               LLC."
       ::= { dot3StatsEntry 13 }






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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


   dot3StatsInRangeLengthErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames received on a particular
               interface with a length field value that falls
               between the minimum unpadded LLC data size and the
               maximum allowed LLC data size inclusive and that
               does not match the number of LLC data octets
               received.

               The count represented by an instance of this
               object also includes frames for which the length
               field value is less than the minimum unpadded LLC
               data size."
       ::= { dot3StatsEntry 14 }

   dot3StatsOutOfRangeLengthFields OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames received on a particular
               interface for which the length field value exceeds
               the maximum allowed LLC data size.

               The count represented by an instance of this
               object is not incremented in implementations that
               observe Ethernet encapsulation conventions (by
               which the IEEE 802.3 length field is interpreted
               as the Ethernet Type field)."
       ::= { dot3StatsEntry 15 }

   dot3StatsInternalMacReceiveErrors OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of frames for which reception on a
               particular interface fails due to an internal MAC
               sublayer receive error. A frame is only counted by
               an instance of this object if it is not counted by
               the corresponding instance of either the
               dot3StatsFrameTooLongs object, the
               dot3StatsAlignmentErrors object, the
               dot3StatsFCSErrors object, the
               dot3StatsInRangeLengthErrors object, or the



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


               dot3StatsOutOfRangeLengthFields object.

               The precise meaning of the count represented by an
               instance of this object is implementation-
               specific.  In particular, an instance of this
               object may represent a count of receive errors on
               a particular interface that are not otherwise
               counted."
       ::= { dot3StatsEntry 16 }


   -- the Ethernet-like Collision Statistics group

   -- Implementation of this group is optional; it is appropriate
   -- for all systems which have the necessary metering

   dot3CollTable OBJECT-TYPE
       SYNTAX  SEQUENCE OF Dot3CollEntry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "A collection of collision histograms for a
               particular set of interfaces."
       ::= { dot3 5 }

   dot3CollEntry OBJECT-TYPE
       SYNTAX  Dot3CollEntry
       ACCESS  not-accessible
       STATUS  mandatory
       DESCRIPTION
               "A cell in the histogram of per-frame collisions
               for a particular interface.  An instance of this
               object represents the frequency of individual MAC
               frames for which the transmission (successful or
               otherwise) on a particular interface is
               accompanied by a particular number of media
               collisions."
       INDEX   { dot3CollIndex, dot3CollCount }
       ::= { dot3CollTable 1 }

   Dot3CollEntry ::=
       SEQUENCE {
           dot3CollIndex
               INTEGER,
           dot3CollCount
               INTEGER,
           dot3CollFrequencies
               Counter



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


       }

   dot3CollIndex OBJECT-TYPE
       SYNTAX  INTEGER
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "The index value that uniquely identifies the
               interface to which a particular collision
               histogram cell pertains.  The interface identified
               by a particular value of this index is the same
               interface as identified by the same value of
               ifIndex."
       ::= { dot3CollEntry 1 }

   dot3CollCount OBJECT-TYPE
       SYNTAX  INTEGER (1..16)
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "The number of per-frame media collisions for
               which a particular collision histogram cell
               represents the frequency on a particular
               interface."
       ::= { dot3CollEntry 2 }

   dot3CollFrequencies OBJECT-TYPE
       SYNTAX  Counter
       ACCESS  read-only
       STATUS  mandatory
       DESCRIPTION
               "A count of individual MAC frames for which the
               transmission (successful or otherwise) on a
               particular interface is accompanied by a
               particular number of media collisions."
       ::= { dot3CollEntry 3 }


   --  802.3 Tests

   -- The ifExtnsTestTable defined in [11] provides a common means
   -- for a manager to test any interface corresponding to a value
   -- of ifIndex.

   -- At this time, one well known test (testFullDuplexLoopBack) is
   -- defined in [11].  For ethernet-like interfaces, this test
   -- configures the MAC chip and executes an internal loopback
   -- test of memory and the MAC chip logic.  This loopback test can



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


   -- only be executed if the interface is offline.  Once the test
   -- has completed, the MAC chip should be reinitialized for network
   -- operation, but it should remain offline.

   -- If an error occurs during a test, the object ifExtnsTestResult
   -- (defined in [11]) will be set to failed(7).  The following two
   -- OBJECT IDENTIFIERs may be used to provided more information as
   -- values for the object ifExtnsTestCode in [11]:

   dot3Errors             OBJECT IDENTIFIER ::= { dot3 7 }

                             -- couldn't initialize MAC chip for test
   dot3ErrorInitError     OBJECT IDENTIFIER ::= { dot3Errors 1 }

                             -- expected data not received (or not
                             -- received correctly) in loopback test
   dot3ErrorLoopbackError OBJECT IDENTIFIER ::= { dot3Errors 2 }


   --  TDR Test

   -- Another test, specific to ethernet-like interfaces,
   -- is Time-domain Reflectometry (TDR) which is defined
   -- as follows:

   dot3Tests   OBJECT IDENTIFIER ::= { dot3 6 }
   dot3TestTdr OBJECT IDENTIFIER ::= { dot3Tests 1 }

   -- A TDR test returns as its result the time interval between the
   -- most recent TDR test transmission and the subsequent detection
   -- of a collision.  This interval is based on a 10 MHz clock and
   -- should be normalized if the time base is other than 10 MHz.
   -- On successful completion of a TDR test, the result is stored
   -- as the value of the appropriate instance of the MIB object
   -- dot3TestTdrValue, and the OBJECT IDENTIFIER of that instance
   -- is stored in the corresponding instance of ifExtnsTestResult
   -- (thereby indicating where the result has been stored).


  --  802.3 Hardware Chipsets

  -- The object ifExtnsChipSet is provided in [11] to identify the
  -- MAC hardware used to communcate on an interface.  The following
  -- hardware chipsets are provided for 802.3:

  dot3ChipSets          OBJECT IDENTIFIER ::= { dot3 8 }
  dot3ChipSetAMD        OBJECT IDENTIFIER ::= { dot3ChipSets 1 }
  dot3ChipSetAMD7990    OBJECT IDENTIFIER ::= { dot3ChipSetAMD 1 }



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


  dot3ChipSetAMD79900   OBJECT IDENTIFIER ::= { dot3ChipSetAMD 2 }

  dot3ChipSetIntel      OBJECT IDENTIFIER ::= { dot3ChipSets 2 }
  dot3ChipSetIntel82586 OBJECT IDENTIFIER ::= { dot3ChipSetIntel 1 }
  dot3ChipSetIntel82596 OBJECT IDENTIFIER ::= { dot3ChipSetIntel 2 }

  dot3ChipSetSeeq       OBJECT IDENTIFIER ::= { dot3ChipSets 3 }
  dot3ChipSetSeeq8003   OBJECT IDENTIFIER ::= { dot3ChipSetSeeq 1 }

  dot3ChipSetNational      OBJECT IDENTIFIER ::= { dot3ChipSets 4 }
  dot3ChipSetNational8390  OBJECT IDENTIFIER ::=
                                            { dot3ChipSetNational 1 }
  dot3ChipSetNationalSonic OBJECT IDENTIFIER ::=
                                            { dot3ChipSetNational 2 }

  dot3ChipSetFujitsu       OBJECT IDENTIFIER ::= { dot3ChipSets 5 }
  dot3ChipSetFujitsu86950  OBJECT IDENTIFIER ::=
                                           { dot3ChipSetFujitsu 1 }

  -- For those chipsets not represented above, OBJECT IDENTIFIER
  -- assignment is required in other documentation, e.g., assignment
  -- within that part of the registration tree delegated to
  -- individual enterprises (see [3]).

  END

6.  Acknowledgements

  This document was produced by the Transmission MIB Working Group.

  This document is based on a document written by Frank Kastenholz of
  Interlan entitled IEEE 802.3 Layer Management Draft M compatible MIB
  for TCP/IP Networks [10].  This document has been modestly reworked,
  initially by the SNMP Working Group, and then by the Transmission
  Working Group, to reflect the current conventions for defining
  objects for MIB interfaces.  James Davin, of the MIT Laboratory for
  Computer Science, and Keith McCloghrie of Hughes LAN Systems,
  contributed to later drafts of this memo. Marshall Rose of
  Performance Systems International, Inc. converted the document into
  its current concise format.  Thanks to Frank Kastenholz of Interlan
  and Louis Steinberg of IBM for their experimentation.

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



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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


      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.

  [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] IEEE, "IEEE 802.3 Layer Management", November 1988.

 [10] Kastenholz, F., IEEE 802.3 Layer Management Draft compatible MIB
      for TCP/IP Networks, electronic mail message to mib-
      [email protected],  9 June 1989.

 [11] McCloghrie, K., Editor, "Extensions to the Generic-Interface
      MIB", RFC 1229, Hughes LAN Systems, Inc., May 1991.

 [12] IEEE, "Carrier Sense Multiple Access with Collision Detection
      (CSMA/CD) Access Method and Physical Layer Specifications",
      ANSI/IEEE Std 802.3-1985.

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






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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


Security Considerations

  Security issues are not discussed in this memo.

Author's Address

  John Cook
  Chipcom Corporation
  118 Turnpike Road
  Southborough, MA  01772

  For more information, contact the chair of the Ethernet MIB working
  group:

  Frank Kastenholz
  Clearpoint Research Inc
  35 Parkwood Drive
  Hopkinton Mass 01748

  Phone: 508-435-2000
  EMail: [email protected]






























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