System and method for WLAN roaming traffic authentication

摘要

A system and method for recognizing traffic generated from an authenticated a device roaming in a wireless local area network and related aspects are provided. An authentication server is arranged to authorize communications traffic originating from a wireless access point to use a roaming service, the traffic comprising an NAT translated IP address. The server first authorizes a WLAN roaming device, and then processes a meta-data message received from a WLAN access point in which the source address of the message comprises the source address of the roaming device at the WLAN access point. The server then determines, from the information provided in the meta-data message when it is received by the authentication server, which includes at this point a NAT translated source address in the meta-data message what the NAT translated source address of traffic from said authenticated roaming device will be. This enables the authentication server to authenticate internet-bound traffic having said NAT translated source address. In this way, all traffic generated by the roaming device whilst that NAT translated IP address is valid is automatically authorized to use a roaming service to access the internet.