Count of received LMI frames which contained an unsupported Information Element (IE) type. This is a 32-bit read-only Counter32, so it only ever increases while the Passport is running and rolls back over to 0 once it wraps -- a monitoring system should poll it periodically and alert on the rate of increase (deltas), not on the raw value, since a rising rate is what signals a real, ongoing problem rather than a one-off event.