Patent ID: 7477911

Claim:
A method of operating a wireless device for push to talk, comprising steps of: (a) receiving a system message in accordance with a cellular wireless carrier protocol, from a cellular wireless network, in the wireless device; (b) obtaining a parameter associated with the cellular wireless carrier protocol, from the received message; (c) sending a request for a registration, needed to allow the wireless device to conduct push to talk communication via the cellular wireless network, from the wireless device and intended for a network element with which the wireless device is required to register in order to conduct the push to talk communication; (d) following failure of the request for registration, delaying a first period of time pre-set in the wireless device; (e) after the first period of time, re-sending the request for the registration, from the wireless device and intended for said network element; (f) following failure of the re-sent request for registration, delaying a second period of time different from the first period of time, the second period of time being based on the parameter associated with the cellular wireless carrier protocol obtained from the received message; and (g) after the second period of time, again re-sending the request for registration, from the wireless device and intended for said network element.