A method comprising: receiving, at or from a station, STA, a plurality of packets, wherein each packet of the plurality of packets includes (i) a set of one or more flag bits, and (ii) a medium access control, MAC, header, and each MAC header contains at least (i) a first address field specifying a receiver address, and (ii) a second address field specifying a transmitter address, wherein at least one of the receiver address and the transmitter address is an association identifier, AID; and processing the MAC header of each packet of the plurality of packets, characterized by determining whether each set of one or more flag bits indicates that the STA was associated with an access point, AP, when the respective packet was generated; in that processing the MAC header of each packet includes using a MAC address in a third address field (60-3, 72, 74) as the MAC address of the STA in packets for which it is determined that the respective set of one or more flag bits indicates that the STA was not associated with an AP when the respective packet was generated; and in that processing the MAC header of each packet does not include using an address in a third address field as the MAC address of the STA in packets for which it is determined that the respective set of one or more flag bits indicates that the STA was associated with an AP when the respective packet was generated. receiving, at or from a station, STA, a plurality of packets, wherein each packet of the plurality of packets includes (i) a set of one or more flag bits, and (ii) a medium access control, MAC, header, and each MAC header contains at least (i) a first address field specifying a receiver address, and (ii) a second address field specifying a transmitter address, wherein at least one of the receiver address and the transmitter address is an association identifier, AID; and each packet of the plurality of packets includes (i) a set of one or more flag bits, and (ii) a medium access control, MAC, header, and (i) a set of one or more flag bits, and (ii) a medium access control, MAC, header, and each MAC header contains at least (i) a first address field specifying a receiver address, and (ii) a second address field specifying a transmitter address, (i) a first address field specifying a receiver address, and (ii) a second address field specifying a transmitter address, wherein at least one of the receiver address and the transmitter address is an association identifier, AID; and processing the MAC header of each packet of the plurality of packets, characterized by determining whether each set of one or more flag bits indicates that the STA was associated with an access point, AP, when the respective packet was generated; in that processing the MAC header of each packet includes using a MAC address in a third address field (60-3, 72, 74) as the MAC address of the STA in packets for which it is determined that the respective set of one or more flag bits indicates that the STA was not associated with an AP when the respective packet was generated; and in that processing the MAC header of each packet does not include using an address in a third address field as the MAC address of the STA in packets for which it is determined that the respective set of one or more flag bits indicates that the STA was associated with an AP when the respective packet was generated.