This Counter64 counts received packets for this pseudowire whose payload size or CESoP/SAToP control-word header was invalid. Because this is the cumulative TdmPwTotalStatistics counter for the pseudowire, tallied since the bin's own start time rather than being reset every short collection interval, a nonzero count here usually points to a configuration mismatch (such as mismatched payload size between the two PW endpoints) or a corrupting device somewhere in the packet path, rather than ordinary network congestion. For example, if this counter starts incrementing right after the far-end pseudowire's payload-size parameter was changed, that timing is a strong hint the two ends are now misconfigured against each other.