 will provide the that need protection basis for establishing the required level of security. Take a complete inventory of all A physical inventory of installed devices should access points and wireless be cross-checked with WLAN logs as well as devices periodic RF sweeps for unknown devices (rogue access points). Locate access points on the interior Internal location will limit the leakage of RF of buildings instead of near transmissions beyond the required operating external walls and windows area and eliminate areas where eavesdropping could take place. Place access points in secured areas Physical security will prevent unauthorised access and manipulation of hardware. Wireless LAN Security Technical Security Measures Technical security measures address issues that need to be considered when configuring a WLAN. Table 8-8 describes some of the key technical security measures recommended in the NIST checklist. Changing SSID and Disabling Broadcasts Unless disabled, the SSID is included in beacon frames transmitted by an access point about ten times every second to alert nearby stations of its presence. Every access point leaves the factory with a default SSID set, and attackers can use these IDs to access unsecured networks if they are not changed from the default values. These default values are widely known and published on the web, and a few of the more well-known ones are "tsunami", "linksys", "wireless" and "default"! War Drivers and War Flyers report that 60-80% of identified WLANs typically still have their security setting in factory default mode, 60% have not changed default SSIDs and under 25% have enabled WEP. These figures are reported from the US, but would likely be similar in the UK. Changing the SSID to another value is the first step in improving security. This should be done when the access point is first configured (Figure 8-12), since entering the SSID is part of the configuration process for each of the client stations that will connect to the access point. A good practice is to use an anony