Patent ID: 7447184

Claim:
A method for identifying physical wireless devices that transmit packets in a local area network (LAN), the method comprising: detecting packets transmitted in the LAN; determining identity information associated with the packets, each identity information associated with a packet identifying a wireless device; computing an approximation to a starting time of the wireless device identified by the each identity information associated with the packet, the computing including subtracting a time stamp field (TSF) value in the packet from the time instant when the packet was detected; and inferring presence of more than one physical wireless device having identical identity information only if a magnitude of a difference between the TSF values in two packets including identical identity information is different from a magnitude of a difference between time instants when the two packets were detected; and none of the approximations to a starting time derived from the two packets is greater than the smaller of the time instants when the two packets were detected.