l, and not to individual access points. Wireless Network Physical Architecture configuration has to be managed for individual access points, the routine management of encryption keys and periodic upgrade of security standards for each installed access point quickly becomes unmanageable. With a centralised security architecture provided by a wireless switch, these management tasks only need to be completed once. WLAN switches also provide a range of additional features, not found in first generation access points, as described in Table 3-3. Access point switch Access points Figure 3-11: Wireless LAN Topology Using a Wireless Switch Lightweight Access Point Protocol Centralising command and control into a wireless LAN switch device introduces the need for a communication protocol between the switch and its dependent access points, and the need for interoperability requires that this protocol is based on an industry standard. The Lightweight Access Point Protocol (LWAPP) standardises communications between switches or other hub devices and access points, and was initially developed by the Internet Engineering Task Force (IETF). Chapter Three Table 3-3: Wireless LAN Switch Features Feature Description Layout planning Automated site survey tools that allow import of building blueprints and construction specifications and determine optimal access point locations. RF management Analysis of management frames received from all access points enables RF signal related problems to be diagnosed and automatically corrected, by adjusting transmit power level or channel setting of one or more access points. Automatic configuration Wireless switches can provide automatic configuration by determining the best RF channel and transmit power settings for individual access points. Load balancing Maximising network capacity by automatic load balancing of users across multiple access points. Policy-based access Access policies can be based on access point control groupings and client lists that specify which access points or groups spec