Supporting efficient and accurate sync/followup timestamps

In one embodiment, a physical (PHY) layer (lower protocol stack layer) of a device may add a timestamp to a received frame, and pass the frame and timestamp up the protocol stack toward a synchronization (sync) recognition layer (upper protocol stack layer). The sync recognition layer determines whether the frame relates to synchronization, and if so, places the timestamp into a data structure along with a frame association for recovery by followup processing. Conversely, in another embodiment, the sync recognition layer may add to a frame for transmission a frame ID having an indication of whether to timestamp the frame and may pass the frame and frame ID down the protocol stack toward the PHY layer. The PHY layer determines whether the frame ID indicates that the frame is to be timestamped, and if so, places a timestamp corresponding to frame transmission into a data structure with the frame ID.