This counts asynchronous LMI status frames received from the DTE, called Update STATUS frames under LMI Rev 1 or Asynchronous STATUS frames under ANSI Annex D and CCITT Annex A, which are the unscheduled notifications a peer sends immediately when a PVC's status changes rather than waiting for the next scheduled poll cycle. An admin values this counter because a rising count means the peer is actively signaling PVC state changes in near-real time, which is exactly the mechanism that lets a lport react quickly to a remote PVC going down. For example, a spike in lportDTEInAsyncStatusFrames right when a customer reports a PVC outage confirms the network promptly received an async notification about that change rather than the admin needing to wait for the next full-status cycle.