METHODS AND APPARATUS FOR USE IN ESTABLISHING SESSION INITIATION PROTOCOL COMMUNICATIONS FOR VIRTUAL PRIVATE NETWORKING

摘要

A communications application, such as a VoIP telephony application, for a mobile communications device, which involves communication in accordance with a session initiation protocol (SIP). One or more processors receive a public IP address assigned to the mobile communication device in a public network; cause a request for a virtual private network (VPN) connection with a private network to be communicated through the wireless transceiver; and refrain from registering with a SIP server for the communications using the public IP address. If the VPN connection is established, they receive a private IP address assigned to the mobile communication device for the VPN connection and cause a request for session registration using the private IP address to be communicated to a SIP server of the private network. If the VPN connection and the private IP address are not obtained within a specified period of time, the session registration is performed using the public IP address. Communications are then performed in accordance with the SIP.