Abstract: A calling party's mobile terminal includes a push-to-talk (PTT) actuator, a transceiver operable to communicate in a half-duplex mode, and a controller. SIP signaling messages sent by the calling party include information associated with one or more customized caller IDs of the calling party. The caller IDs are customized, stored, and managed by the calling party. A remote party's mobile terminal receives the SIP signaling messages, and outputs the calling party's customized caller ID to the remote party to identify the calling party.

Abstract: A method for invoking a silent mode for a Push-to-talk technology (“PTT”) mobile terminals. When a mobile terminal user selects the silent mode option, the mobile terminal sends a message to a PTT server that maintains a PTT user accept list. This message instructs the PTT server to disable a global setting that controls the PTT accept list. Once disabled, all incoming PTT calls are in manual answer mode and require user interaction to be accepted. The calling party is notified that the called party is not in auto-answer mode and that the PTT invitation must be accepted before a PTT call session can occur. When exiting silent mode, the user again selects the silent mode option. This causes the mobile terminal to send a message to the PTT server instructing the PTT server to enable the global setting that controls the accept list, thereby enabling auto-answer mode.

Abstract: A method is provided of distributing push-to-talk group identifiers. When the PTT group is created, the user terminal for the group creator automatically generates and sends a group identification message containing the group identifier to the other group members. The user terminals receiving the message recognize that it contains a PTT group identifier and execute and group list update process to add the new group to a locally stored group list or contact list.

Abstract: A calling party's mobile terminal includes a push-to-talk (PTT) actuator, a transceiver operable to communicate in a half-duplex mode, and a controller. SIP signaling messages sent by the calling party include information associated with one or more customized caller IDs of the calling party. The caller IDs are customized, stored, and managed by the calling party. A remote party's mobile terminal receives the SIP signaling messages, and outputs the calling party's customized caller ID to the remote party to identify the calling party.