METHOD FOR A SESSION INITIATION PROTOCOL PUSH-TO-TALK TERMINAL TO INDICATE ANSWER OPERATING MODE TO AN INTERNET PROTOCOL PUSH-TO-TALK NETWORK SERVER.

摘要

A push-to-talk communication device including an operating answer mode indicates that operating answer mode to a Session Initiation Protocol / Internet Protocol based push-to-talk network server. The method includes employing as the operating answer mode of the push-to-talk communication device one of an automatic-answer mode, an always-automatic-answer mode and a manual-answer mode. A Session Initiation Protocol / Internet Protocol core network is employed including a Session Initiation Protocol / Internet Protocol push-to-talk network server. The operating answer mode is indicated in a Session Initiation Protocol message from the push-to-talk communication device to the Session Initiation Protocol / Internet Protocol push-to-talk network server over the Session Initiation Protocol / Internet Protocol core network.