Patent attributes
A novel method and apparatus for coping with lost acknowledgements from power-saving stations in local-area networks are disclosed. In particular, the illustrative embodiment modifies the access point's and power-saving stations' protocols to prevent repeated lost acknowledgements from occurring. An access point, after transmitting the final downlink frame of a sequence to a station and receiving an acknowledgement from the station, transmits a “double acknowledgement” to the station. A power-saving station, after receiving the final downlink frame of a sequence and transmitting an acknowledgement to the access point, stays awake until one of the following occur: (i) the station receives a double acknowledgement, (ii) the station observes a frame transmitted from the access point to another station, or (iii) the station observes that the shared-communications channel of the local-area network is idle for a particular time interval.