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.