Another issue with WLANs is the compromise between security and ease of use. Most suppliers want to ensure that their equipment is easy to use 'out of the box'. To achieve this they use well-known default settings that do not fully exploit the security features available. This means that it is essential to configure a newly deployed WLAN correctly to take maximum advantage of the security features that exist.

A typical WLAN has several mobile devices, such as PDAs, mobile phones, and laptop computers that access the enterprise information through hardware called Access Points. The way in which these access points are configured is critical to security. For example you need to change the Service Set Identifier (SSID) or network name from the default to something private and you should enable WEP (described above). You should also configure to only allow equipment that you recognize access the WLAN. This means you should statically assign IP addresses to hardware/MAC addresses and only use dynamic address assignment where IP addresses are only assigned to recognized MAC addresses.

The critical WLAN security issue relates to the placement of firewalls. Firewalls are used to prevent outsiders from gaining direct access into the enterprise Local Area Network. Hence it is assumed that it is safe to connect business critical servers and applications directly to the LAN. If a WLAN is connected directly to these business critical systems then it is possible to bypass the firewall by gaining access to the WLAN. Therefore it is essential to separate out WLANs and to connect them into the enterprise via a firewall. It is also advisable to strengthen the access controls on your business critical servers to provide added protection if the firewall is breached.

The cheap and easy availability of wireless equipment poses an insidious threat by making it possible for individuals with an organization to purchase and connect the wireless access points directly onto the corporate LAN thus compromising your security. Unicenter from Computer Associates provides technology that is able to automatically discover the existence of WLAN access points and can be used to detect unauthorised additions to the corporate LAN.


Computer Associates are exhibiting at Infosecurity Europe, Europe's largest and most important information security event. Now in its 8th year, the show features Europe's most comprehensive FREE education programme, and over 200 exhibitors at the Grand Hall at Olympia from 29th April - 1st May 2003.



Infosecurity Europe is Europe's largest and most important information security event. Now in its 8th year, the show features Europe's most comprehensive FREE education programme, and over 200 exhibitors at the Grand Hall at Olympia from 29th April - 1st May 2003. www.infosec.co.uk