A communication device is arranged to delay a procedure for joining a network until it detects activity on the network, for example until the communication device is within range of network. In response to a positive detection of network activity, the communication device broadcasts its address to other communication devices already connected to the network. In response, a message containing a list of addresses of the other communication devices is sent by a selected one of the other communication device, for example, the one communication device that most recently joined the network. Each communication device is arranged to send a message once, so that only one message containing the address is sent to a communication device joining the network. If no network activity is detected, the communication device may continue to broadcast its address periodically at gradually increasing time intervals.