Abstract: A wireless-LAN terminal comprises a wired-LAN controller, a wireless modem and an access controller intervening between the wired-LAN controller and the wireless modem. In the access controller, the termination of data reception and the occurrence of a transmission request are detected by monitoring a frame-sense (FS) signal and a request-to-send (RTS) signal, respectively. An IFS period is generated by a delay timer when the data reception is terminated and a random amount of time is generated by using a backoff algorithm when the transmission request occurs during a transmission inhibition period. The data transmission is waited until the random amount of time comes to an end, and the data transmission is started when the random amount of time has elapsed and the transmission channel is available. Since a backoff period is determined randomly for each terminal, there is a remarkably reduced probability that a plurality of terminals concurrently start the media access for data transmission.