This read-only counter tracks the number of PVC hello Ack PDU frames received in the VC entry of the calling side for this leaf, the acknowledgment counterpart to cktLeafHelloCounter, confirming the called side is responding to the hellos it received. Comparing hello-sent-equivalent activity against cktLeafHelloAckCounter lets an admin determine if the handshake is bidirectionally healthy or if hellos are going out unanswered. An engineer seeing cktLeafHelloCounter incrementing normally but cktLeafHelloAckCounter stalled would suspect the called side isn't properly acknowledging hellos, likely presaging a connection timeout.