Push-to-talk wireless telecommunications system utilizing an voice-over-IP network

• US 7,801,953 B1
• Filed: 12/21/2001
• Issued: 09/21/2010
• Est. Priority Date: 02/12/2001
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Denman, Robert E., Derryberry, Barbara, Parameswar, Sriram
• Primary Examiner(s): PHILLIPS, HASSAN A
• Application Number:
  US10/028,086
• Time in Patent Office: 3,196 Days
• Field of Search: None
• US Class Current: 709/204
• CPC Class Codes: H04L 2101/60 Types of network addresses
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 65/4038 with floor control
• CPC Class Codes: H04L 65/4061 Push-to services, e.g. push-to-talk or push-to-video
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 76/45 for Push-to-Talk [PTT] or Push-to-Talk over cellular [PoC] services
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14

Abstract

A method and system to provide push-to-talk from one user to another in a wireless packet data telecommunications network is described. The system may include: a wireless communication network including push-to-talk (PTT) functionality, with a Session Initiation Protocol (SIP) Proxy Server; a SIP Registrar and Location Server operable to store contact addresses of active mobile devices; a Realtime Transport Protocol (RTP) Media Gateway (PTT Server) operable to function as a call endpoint for each of a plurality of mobile devices wherein the plurality of mobile devices are segmented into membership groups, the PTT Server further operable to multicast a communication from one member of the group to the other members of the group; and an Internet Protocol (IP) network interconnecting the SIP Proxy server, the SIP Registrar and Location Server, and the PTT Server.

Claims

1. A method for PTT private calls for users in a wireless communications network, comprising:

selecting a called party private identification for a private call by a calling party on a mobile device;

selecting a PTT function on the mobile device;

transmitting a SIP SUBSCRIBE including the calling and called parties private identifications to request a speech token;

redirecting the SIP SUBSCRIBE to a PTT Server for purposes of removing the calling party and the called party from a multicast group;

receiving an acknowledge message that includes a speech token;

communicating speech packets from the calling party to the called party in a half-duplex manner;

transmitting a SIP SUBSCRIBE to release the speech token; and

notifying the calling and called parties that the group'"'"'s speech token is available.

2. The method of claim 1 wherein notifying the calling party that the group'"'"'s speech token is available includes sending a response to the SIP SUBSCRIBE that requested releasing of the private-call speech token.

3. The method of claim 1 wherein notifying the called party that the group'"'"'s speech token is available includes sending a SIP INFO.

4. The method of claim 1 wherein notifying the called party that the group'"'"'s speech token is available includes sending a SIP NOTIFY.

5. The method of claim 1 wherein notifying the calling and called parties that the group'"'"'s speech token is available includes multicasting to the calling and called parties a pre-stored tone from the PTT Server.

6. The method of claim 1 further including:

reinstating the calling party and the called party as part of the group upon termination of the private call.

7. The method of claim 6 wherein reinstating the calling and called party as part of the group includes restoring the IP addresses of the parties'"'"' mobile devices to the group'"'"'s multicast group.

8. A method for PTT private calls for users in a wireless communication network where the users are registered as members of a multicast group, comprising:

entering a called party private identification for a private call by a calling party on a mobile device;

transmitting the calling and called parties'"'"' private identifications by pressing a PTT button on the mobile device;

redirecting the called party private identification to a PTT Server, the PTT server operable to temporarily remove the calling party and the called party from the multicast group;

transmitting calling party information to the called party from the PTT Server;

communicating directly from the calling party and the called party.

9. The method of claim 8 wherein the transmitting the calling party information uses a SIP NOTIFY message.

10. The method of claim 8 wherein the transmitting the calling party information uses an INFO message.