This counter provides a count of network timer expiries, and to some extent host or switch timer expiries, incrementing on any network timer expiry or on receipt of a RELEASE or RELEASE COMPLETE with cause 102, recovery on timer expiry. It counts calls where a signaling protocol timer ran out waiting for an expected response, a symptom distinct from an explicit rejection, meaning a message that should have arrived within protocol timing simply never showed up. This counter rising during periods of high signaling load or SSCOP instability suggests the signaling channel is too slow or lossy to keep up with the protocol's timing expectations, rather than calls being actively rejected.