An IEEE standard for wireless LANs. 802.11b networks range from 65 to 100 feet of the maximum data transfer rate (11 Mbps) desired; as the signal weakens with greater distances from the base unit, the protocol steps down to 5.5 Mbps and finally to 2 Mbps. 802.11b are capable of penetrating most walls (except thick concrete) at the cost of some range, 802.11b signals employ the 2.4 GHz radio spectrum and uses Carrier Sense Multiple Access with Collision Avoidance (CSMA/ CA) to control media access. See access point, ad hoc network, AirPort, CSMA/CD, IEEE, infrastructure mode, WiFi, WiFi Alliance.