METHODS FOR MANAGING PRESENCE INFORMATION IN A REAL-TIME COMMUNICATIONS NETWORK

• US 20070288621A1
• Filed: 05/11/2007
• Published: 12/13/2007
• Est. Priority Date: 05/11/2006
• Status: Active Grant

• Current Assignee: Sonim Technologies, Inc.
• Original Assignee: Sonim Technologies, Inc.
• Inventors: Gundu, Veerabhadra, Purayil, Nizar
• Granted Patent: US 7,707,286 B2
• Time in Patent Office: Days
• US Class Current: 709/223
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 65/4061 Push-to services, e.g. push-to-talk or push-to-video
• CPC Class Codes: H04L 67/54 Presence management, e.g. monitoring or registration for receipt of user log-on information, or the connection status of the users
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 76/45 for Push-to-Talk [PTT] or Push-to-Talk over cellular [PoC] services
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals

Abstract

Methods for updating presence information between a first user equipment (UE) and a second UE over a communications network are presented including: on an INVITE message delivery failure to the second UE from the first UE, sending a first PUBLISH message on behalf of the second UE to a presence server by a communications server; sending a NOTIFY message to the first UE by the presence server; and setting a current presence status of the second UE to UNAVAILABLE. In some embodiments, methods further include: if an immediately previous presence status of the second UE is set to AVAILABLE, sending a NOTIFY message to all watchers of the second UE to indicate the current presence status of the second UE. In some embodiments, the first PUBLISH message utilizes a user-agent header to indicate that the communications server originated the first PUBLISH message.

Claims

1. A method for updating presence information between a first user equipment (UE) and a second UE over a communications network, the method comprising:

on an INVITE message delivery failure to the second UE from the first UE, sending a first PUBLISH message on behalf of the second UE to a presence server by a communications server;

sending a NOTIFY message to the first UE by the presence server; and

setting a current presence status of the second UE to UNAVAILABLE.

2. The method of claim 1 further comprising:

if an immediately previous presence status of the second UE is set to AVAILABLE, sending a NOTIFY message to all watchers of the second UE to indicate the current presence status of the second UE.

3. The method of claim 2 wherein the first PUBLISH message utilizes a user-agent header to indicate that the communications server originated the first PUBLISH message.

4. The method of claim 3 further comprising:

utilizing the first PUBLISH message to indicate the current presence status of the second UE until the presence server receives a second PUBLISH message from the second UE; and

when the presence server receives the second PUBLISH message, discarding the first PUBLISH message.

5. The method of claim 2 wherein the NOTIFY message and the first PUBLISH message each utilized an originator field to indicate a source of the current presence status.

6. The method of claim 5 wherein the NOTIFY message and the first PUBLISH message are Presence Information Data Format (PIDF) compliant.

7. The method of claim 6 wherein the presence server maintains presence information from any source as a separate PUBLISH session.

8. The method of claim 1 wherein the communications network is a Push-to-Talk over Cellular (PoC) system.

9. The method of claim 8 wherein the communications server includes a PoC server for handling messages and media between the first UE and the second UE.

10. The method of claim 9 wherein the first UE and the second UE each include:

a PoC client for communicating with the PoC server; and

a user interface for providing user input to the PoC system and for providing PoC system output to a user.

11. The method of claim 9 wherein the messages and media are transmitted over an access network and an SIP/IP core.

12. The method of claim 10, wherein the PoC client of the second UE sends a message to the presence server when a lost network connection is restored, the message selected from the group consisting of:

a PUBLISH message and a SUBSCRIBE refresh message.

13. A method for updating presence information between a first user equipment (UE) and a second UE over a communications network, the method comprising:

on a NOTIFY message delivery failure to the second UE from a presence server, starting a grace timer;

sending a first presence status to the first UE that the second UE is UNAVAILABLE;

storing any pending presence updates of the second UE on the presence server; and

if the grace timer expires, sending a second NOTIFY message to the second UE,

if the second NOTIFY message is delivered, restoring a SUBSCRIBE session of the second UE,

sending a second presence status to the first UE that the second UE is AVAILABLE,

sending all pending presence updates to the second UE, and

if the second NOTIFY message is not delivered, deleting the SUBSCRIBE session of the second UE.

14. The method of claim 13 further comprising:

if the presence server receives a PUBLISH message from the second UE, restoring the SUBSCRIBE session of the second UE;

sending the second presence status to the first UE that the second UE is AVAILABLE; and

sending all pending presence updates to the second UE.

15. The method of claim 14 further comprising:

if the presence server receives a SUBSCRIBE message from the second UE, restoring the SUBSCRIBE session of the second UE;

sending the second presence status to the first UE that the second UE is AVAILABLE; and

sending all pending presence updates to the second UE.

16. The method of claim 15 wherein the presence server is configured with a maximum threshold UE limit for determining whether to send substantially simultaneous NOTIFY messages to all users, such that when the maximum threshold UE limit is exceeded, the NOTIFY message delivery failure is ignored and the substantially simultaneous NOTIFY messages are not sent.

17. The method of claim 13 wherein the grace timer is set to a static value, wherein the static value is set to a value lower than a configured SUBSCRIBE timer.

18. The method of claim 13 wherein the grace timer is set to a dynamic value, wherein the dynamic value is set to a value equal to a time remaining in the SUBSRIBE session plus one minute.

19. The method of claim 13 wherein the communications network is a Push-to-Talk over Cellular (PoC) system.

20. The method of claim 19 wherein the communications server includes a PoC server for handling messages and media between the first UE and the second UE.

21. The method of claim 20 wherein the first UE and the second UE each include:

a PoC client for communicating with the PoC server; and

a user interface for providing user input to the PoC system and for providing PoC system output to a user.

22. The method of claim 20 wherein the messages and media are transmitted over an access network and an SIP/IP core.

23. The method of claim 21, wherein the PoC client of the second UE sends a message to the presence server when a lost network connection is restored, the message selected from the group consisting of:

a PUBLISH message and a SUBSCRIBE refresh message.

24. A method for updating presence information between a first user equipment (UE) and a second UE over a communications network, the method comprising:

on a NOTIFY message delivery failure to the second UE from a presence server, requesting a new PUBLISH message from the second UE by the presence server;

sending a first presence status to the first UE that the second UE is UNAVAILABLE;

storing any pending presence updates of the second UE on the presence server; and

if the second UE responds to the new PUBLISH message request before an original PUBLISH timer expires, restoring a SUBSRIBE session of the second UE,

sending a presence status to the first UE that the second UE is AVAILABLE, and

sending all pending presence updates to the second UE.

25. The method of claim 24 wherein the PUBLISH timer is set to an interval in the range of approximately 30 to 60 minutes in a low-bandwidth network and 5 to 15 minutes in a high-bandwidth network.