This is a running counter of the total number of packets received (incoming) on this specific pseudowire, giving a basic traffic-volume metric for the customer service it carries. This counter is the most direct way to confirm a pseudowire is actually passing meaningful traffic rather than just being administratively and operationally up with no real customer usage. A pseudowire whose incoming packet count has stopped incrementing over time, despite showing an up operational state, would indicate silent traffic loss worth investigating even though the control-plane state looks healthy.