MIB Object Definitions for Counters
Implementors may wish to consider selecting the ShortEventMaxTime towards the lower end of the allowed tolerance range to accommodate bit losses suffered through physical channel devices not budgeted for within this standard.
The approximate minimum time for rollover of this counter is 16 hours." Reference: IEEE 802.3 Rptr Mgt, 19.2.6.2, aShortEvents
Runts
"This counter is incremented by one for each CarrierEvent on this port that meets one of the following two conditions. Only one test need be made.
a)The ActivityDuration is greater than ShortEventMaxTime and less than ValidPacketMinTime and the CollisionEvent signal is deasserted.
b)The OctetCount is less than 64, the ActivityDuration is greater than ShortEventMaxTime and the CollisionEvent signal is deasserted. ValidPacketMinTime is greater than or equal to 552 bit times and less than 565 bit times.
An event whose length is greater than 74 bit times but less than 82 bit times shall increment either the shortEvents counter or the runts counter but not both. A CarrierEvent greater than or equal to 552 bit times but less than 565 bit times may or may not be counted as a runt.
ValidPacketMinTime has tolerances included to provide for circuit losses between a conformance test point at the AUI and the measurement point within the state machine.
Runts usually indicate collision fragments, a normal network event. In certain situations associated with large diameter networks a percentage of collision fragments may exceed ValidPacketMinTime.
The approximate minimum time for rollover of this counter is 16 hours." Reference: IEEE 802.3 Rptr Mgt, 19.2.6.2, aRunts
Collisions
"This counter is incremented by one for any CarrierEvent signal on any port for which the CollisionEvent signal on this port is also asserted.
The approximate minimum time for rollover of this counter is 16 hours." Reference: IEEE 802.3 Rptr Mgt, 19.2.6.2, aCollisions
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