This counts LMI STATUS frames, the basic keepalive-style link-integrity-verification messages rather than full-status updates, received by the DTE side from the DCE since the last system reset. An admin watches this counter to confirm the LMI signaling channel is actively exchanging keepalives; a value that stops incrementing while the port is otherwise up suggests LMI has stalled even though the physical layer looks fine. For example, if lportDTEInStatusFrames stops climbing while lportDTEOutPollFrames keeps increasing, the DTE is polling but getting no STATUS responses back, pointing to a one-way LMI problem.