Patent attributes
An access point generates and transmits, to first client stations and a second client station, a downlink multi-user (MU) physical layer (PHY) data unit having respective media access control (MAC) data units for i) the first client stations and ii) the second client station. The downlink MU PHY data unit includes an indication that the first client stations are to acknowledge the downlink MU PHY data unit in an uplink MU PHY data unit, and indicates that the second client station is to acknowledge the downlink MU PHY data unit in another uplink PHY data unit separate from the uplink MU PHY data unit. The access point receives, from the multiple first client stations, the uplink MU PHY data unit, and polls the second client station to prompt the second client station to acknowledge, in another uplink PHY data unit, that the second client station received the downlink MU PHY data unit.
