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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


        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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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


                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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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


        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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RFC 1284                 ETHERNET-LIKE OBJECTS             December 1991


    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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