System and method for providing a recovery mode in a session initiation protocol (SIP) environment

• US 8,254,552 B2
• Filed: 01/06/2005
• Issued: 08/28/2012
• Est. Priority Date: 01/06/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Harton, David C., Frisk, Richard A., Bao, Ho, Entrop, Clint D.
• Primary Examiner(s): Elahee, Md S
• Application Number:
  US11/031,368
• Publication Number:
  US 20060146798A1
• Time in Patent Office: 2,791 Days
• Field of Search: 370/352, 370/395.3, 370/225, 455/519, 455/518, 455/507, 709/224, 37926501-2661, 379/88.17, 379/88.18, 37920201-20601, 379/221.03, 379/221.04, 379/221.15
• US Class Current: 379/221.03
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A method to be executed in a session initiation protocol (SIP) environment is provided that includes detecting, by a first agent, a potential lost connection associated with a signaling path. The signaling path couples a first endpoint and a second endpoint and is operable to exchange signaling data. The potential lost connection is associated with a call between the first and the second endpoint, the first agent being associated with the first endpoint. The method also includes communicating a reinvite to a second agent that is associated with the second endpoint in order to determine whether the call between the first endpoint and the second endpoint is active.

Claims

1. A method for facilitating a call in a session initiation protocol (SIP) environment, comprising:

detecting, by a first agent, a potential lost connection of a signaling path coupling a first endpoint and a second endpoint, the signaling path configured to exchange signaling data for a call between the first and the second endpoint, the first agent being associated with the first endpoint;

determining that a bearer path exchanging data for the call between the first and the second endpoint is functional while the signaling path coupling the first and the second endpoint for the call is lost, the bearer path configured to exchange data for the call between the first and the second endpoint;

communicating a reinvite to a second agent that is associated with the second endpoint in order to determine whether the call between the first endpoint and the second endpoint is active; and

maintaining the bearer path for the call while the signaling path is lost.

2. The method of claim 1, wherein the bearer path remains intact while it is determined whether the call is active.

3. The method of claim 1, further comprising:

identifying that the reinvite has not been successfully responded to;

communicating a BYE to the second agent; and

tearing down the call.

4. The method of claim 1, wherein the reinvite includes a tag that comprises a selected one or more of a call ID, source information, and destination information, all of which correspond to an original invite of the call.

5. The method of claim 1, wherein the first agent communicates one or more reinvites on a periodic basis.

6. The method of claim 1, wherein if the reinvite is not answered, a cleanup operation is initiated in order to conserve resources.

7. The method of claim 1, wherein the first agent is operable to distinguish a failure in the bearer path that carries data between the first and the second endpoint and a failure in the signaling path.

8. The method of claim 1, wherein the first and second endpoints are Internet protocol (IP) telephones and are operable to deliver voice data to each other.

9. The method of claim 1, wherein the first agent is included in a Call Manager element, and wherein the first agent is a back-to-back user agent (B2BUA).

10. An apparatus for facilitating a call in a session initiation protocol (SIP) environment, comprising:

a first agent operable to;

detect a potential lost connection of a signaling path coupling a first endpoint and a second endpoint, the signaling path configured to exchange signaling data for a call between the first and the second endpoint, the first agent being associated with the first endpoint,

determine that a bearer path exchanging data for the call between the first and the second endpoint is functional while the signaling path coupling the first and the second endpoint for the call is lost, the bearer path configured to exchange data for the call between the first and the second endpoint,

communicate a reinvite to a second agent that is associated with the second endpoint in order to determine whether the call between the first endpoint and the second endpoint is active; and

maintaining the bearer path for the call while the signaling path is lost.

11. The apparatus of claim 10, wherein the bearer path remains intact while it is determined whether the call is active.

12. The apparatus of claim 10, wherein the first agent is further operable to:

identify that the reinvite has not been successfully responded to;

communicate a BYE to the second agent; and

tear down the call.

13. The apparatus of claim 10, wherein the reinvite includes a tag that comprises a selected one or more of a call ID, source information, and destination information, all of which correspond to an original invite of the call.

14. The apparatus of claim 10, wherein the first agent is included in a Call Manager element.

15. The apparatus of claim 10, wherein the first agent is a back-to-back user agent (B2BUA).

16. One or more memories of a computer encoded with software for facilitating a call in a session initiation protocol (SIP) environment, the software when executed by a computer operable to:

detect a potential lost connection of a signaling path coupling a first endpoint and a second endpoint, the signaling path configured to exchange signaling data for a call between the first and the second endpoint;

determining that a bearer path exchanging data for the call between the first and the second endpoint is functional while the signaling path coupling the first and the second endpoint for the call is lost, the bearer path configured to exchange data for the call between the first and the second endpoint;

communicate a reinvite in order to determine whether the call between the first endpoint and the second endpoint is active; and

maintaining the bearer path for the call while the signaling path is lost.

17. The one or more memories of claim 16, wherein the software is further operable to:

identify that the reinvite has not been successfully responded to;

communicate a BYE; and

tear down the call.

18. The one or more memories of claim 16, wherein the software is further operable to:

respond, if the reinvite is not answered, by performing a cleanup operation in order to conserve resources.

19. The one or more memories of claim 16, wherein the software is further operable to:

distinguish a failure in the bearer path that carries data between the first and the second endpoint and a failure in the signaling path.

20. The one or more memories of claim 16, wherein the reinvite is communicated on a periodic basis.