he information source and destination stations can use to alter frame bits (pieces of data) to avoid disclosure to eavesdroppers. The solution includes encryption. WLAN should provide firewall protection, preventing unauthorized access. A WLAN solution should preferably be based on IPsec. Encryp- tion/decryption and authorization keys could also be employed to provide authentication, automatic security association management, and to protect wireless traffic. Network access control can be implemented by using a service set identifier (SSID) associated with an access point (AP) or group of APs. The SSID acts as a simple password for network access and provides minimal security since wireless clients can share it. Security 802. 1x is related to the 802.11 standards and covers two distinct areas: network access restriction through the use of authentication, and data integrity through WEP key rotation. The 802. 1x standard recommends the use of a RADIUS server in conjunction with two data communication protocols: extensible authentication protocol (EAP) and transport layer security (TLS). 802.1x implementations also improve data encryption through rotation of the WEP 128 key. 6.15 SUMMARY WITH IPsec AND FP FOCUS With the proliferation of access methods to the Internet in mind, and a development towards more sophisticated attacks from hackers, the conclusion is that protection must be extended beyond access restrictions. In particular, the traffic itself must be protected to a large extent. There are a number of protection methods for different applications, such as TLS/SSL for WWW traffic, FTP and Telnet, Wireless TLS for WAP WWW, and S/MIME for E-mail. A more general protection is related to the common IP layer. The biggest Internet layer security protocol family is IPsec, which is a fairly complex umbrella IETF standard, developed since 1995. IPsec is an open, vendor-independent architecture and a kind of VPN standard. It can also be used for leased lines and frame relay traffic. The main aim of IPsec, however, is t