摘要:
PURPOSE: A handover processing method for a telephone terminal supporting both a wireless mode and a mobile mode is provided to maintain optimal call connection state by selecting the most proper interface according to the strength of a wireless signal. CONSTITUTION: A mobile phone function unit requests a handover thereto from an SIP server if the strength of a wireless signal drops below a critical value during a call connection. According to the request from the handover request of the mobile phone function unit, the SIP server(17) tries the call connection to a mobile phone function unit through a gateway(18). If the mobile phone function unit receives the tried call, the gateway forms the call connection path between the mobile phone function unit and a terminal of the other party. The mobile phone function unit terminates the connection between the mobile phone function unit and the terminal of the other party.