A station increases this counter when it detects a packet addressed to itself but cannot copy that frame due to lack of resource.

GENERAL: Soft Errors

The token ring architecture includes an inherent error monitoring protocol. Each station records local errors. These errors are generically referred to as 'soft errors'. Soft errors represent intermittent faults that temporarily disrupt normal operation of the ring. Stations periodically transmit their soft error counters onto the ring where they can be received by any stations which have the ring error monitor functional address active.

There are two categories of soft error. Isolating errors and Non-isolating errors. An isolating error will be reported by exactly one station on the ring and the error is known to have occurred between that station and its upstream neighbour. The second category are non-isolating. That is, errors of this nature may be seen and reported by more than one ring station. With these errors it is not possible to resolve the source of the error.