A method for communicating between a cellular system and a client terminal such as a mobile terminal by way of a standard wireless LAN and the Internet allows data communications to traverse the core of the cellular network, thereby allowing monitoring of the time and volume usage by the subscriber for billing purposes. The mobile terminal has a communication protocol for communicating with the wireless LAN, over which is a EAP/EAPOL protocol. A Radio Adaptation Layer protocol overlies the EAP/EAPOL protocol. At the cellular system, a Serving GPRS Support Node establishes initial control contact with the mobile terminal by way of EAP/EAPOL. During authentication, the Support Node gives the mobile terminal parameters for an alternative tunnel connection. Once authorization is complete, the mobile terminal closes the EAP/EAPOL connection and opens a new connection tunnel to the Support Node using the parameters.