APC IP DSLAM Betriebsanweisung PDF herunterladen (Seite 331)

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detected on a particular interface later than

one slotTime into the transmission of a packet.

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.

This counter does not increment when the

interface is operating in full-duplex mode.

Discontinuities in the value of this counter can

occur at re-initialization of the management

system, and at other times as indicated by the

value of ifCounterDiscontinuityTime.

Excess Collisions

Frames

A count of frames for which transmission on a

particular interface fails due to excessive

collisions. This counter does not increment

when the interface is operating in full-duplex

mode. Discontinuities in the value of this

counter can occur at re-initialization of the

management system, and at other times as

indicated by the value of

ifCounterDiscontinuityTime.

Mac Tx Errors Frames

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, or the

dot3StatsCarrierSenseErrors 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. For interfaces operating at

10 Gb/s, this counter can roll over in less than

5 minutes if it is incrementing at its maximum

rate. Since that amount of time could be less

than a management station's poll cycle time, in

order to avoid a loss of information, a

management station is advised to poll the

dot3HCStatsInternalMacTransmitErrors object

for 10 Gb/s or faster interfaces. Discontinuities

in the value of this counter can occur at re-

initialization of the management system, and at

other times as indicated by the value of

ifCounterDiscontinuityTime.

Carrier Sense Errors

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. This counter does not

increment when the interface is operating in

full-duplex mode. Discontinuities in the value of

this counter can occur at re-initialization of the

management system, and at other times as

indicated by the value of

ifCounterDiscontinuityTime.

Too Long Frames

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 pertain are, according to the

conventions of IEEE 802.3 Layer

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