This is a cumulative count of packets received by this specific station since the last reset, the packet-level counterpart to cdx6500allstationsCharInTot for this individual device on a shared line. An admin uses this to identify, at the packet level, which specific station on a multi-drop port has been most active, useful for protocols like SDLC where packet counts matter more than raw character counts. For example, a station with an unusually high PktInTot compared to its port-mates would be the first one checked when troubleshooting excessive traffic on a shared line.