This counts the total number of BFD control packets received from the peer for this session, the receive-side counterpart to the transmit counter, confirming the remote end is actually sending its own keepalives back. An admin compares this to the transmit count and to the session's uptime to spot an asymmetric failure, where one direction of the BFD exchange is silently failing even though the session hasn't yet declared down. For example, a steadily climbing TotalTx but a stalled TotalRx would indicate the peer has stopped responding, which typically precedes an imminent session-down transition once the detection timer expires.