Enhanced refresh in SIP network

• US 20070294345A1
• Filed: 06/14/2006
• Published: 12/20/2007
• Est. Priority Date: 06/14/2006
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Bangalore, Manjunath, Kumarasamy, Parameswaran, Parameswaran, Kavithadevi
• Granted Patent: US 8,223,748 B2
• Time in Patent Office: Days
• US Class Current: 709/204
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]

Abstract

Embodiments of the present invention provide techniques for refreshing a session. A session is refreshed using a refresh message that is enhanced for a refresh. For example, the refresh message does not include an SDP or any other message body. The message includes only a reduced header. This reduces time spent building and parsing the refresh message. Also, less bandwidth is used in sending the refresh messages.

Claims

1. A method for refreshing a session, the method comprising:

generating a refresh message to initiate a refresh of a session at a refreshee, the refresh message not including a body;

sending a refresh message to the refreshee;

receiving a response message for the refresh that has been performed for the session; and

determining if the session is active or inactive based on the received response message.

2. The method of claim 1, wherein the refresh message includes a reduced header that only includes mandatory fields as defined in SIP.

3. The method of claim 1, wherein the body does not include an SDP.

4. The method of claim 1, wherein the response message is a first type of message if the session is active and a second type of message if the session is inactive.

5. The method of claim 4, wherein the first type of message is a SIP 200 OK message and the second type of message is a SIP 481 Call/Transaction does not exist message.

6. The method of claim 1, further comprising:

sending a negotiation message to the refreshee indicating the refresh method is supported; and

receiving a response from the refreshes indicating whether the refreshes supports the refresh method.

7. The method of claim 6, further comprising sending a message with a body if the refresh method is not supported.

8. The method of claim 1, wherein the refresh message includes a header consisting of a message field, From field, TO field, call-ID field, and Cseq field as defined in SIP.

9. A method for refreshing a session, the method comprising:

receiving a refresh message for a session from a refresher, the refresh message not including a body;

parsing the refresh message to determine the session to refresh;

generating a response message, the response message not including a body; and

sending a response message, the response message indicating a result of the refresh performed for the session.

10. The method of claim 9, wherein the refresh message and/or the response message include a reduced header that only includes mandatory header fields as defined in SIP.

11. The method of claim 9, wherein the response message is a first type of message if the session is active and a second type of message if the session is inactive.

12. The method of claim 11, wherein the first type of message is a SIP 200 OK message and the second type of message is a SIP 481 Call/Transaction does not exist message.

13. The method of claim 9, wherein the body does not include an SDP.

14. The method of claim 9, further comprising:

receiving a negotiation message from the refresher indicating the refresh method is supported; and

sending a response from the refreshee indicating whether the refresh method is supported.

15. The method of claim 14, further comprising receiving a message with the body if the refresh method is not supported.

16. The method of claim 9, wherein the refresh message includes a header consisting of a message field, From field, TO field, call-ID field, and Cseq field as defined in SIP.

17. A network device configured to refresh a session, the network device comprising:

a session refresher configured to;

generate a refresh message to initiate a refresh of a session at a refreshee, the refresh message not including a body; and

send a refresh message to the refreshee;

an inactive session identifier configured to;

receive a response message for the refresh that has been performed for the session; and

determining if the session is active or inactive based on the received response message.

18. The network device of claim 17, wherein the refresh message includes a reduced header that only includes mandatory fields as defined in SIP.

19. The network device of claim 17, wherein the body does not include an SDP.

20. The network device of claim 17, wherein the response message is a first type of message if the session is active and a second type of message if the session is inactive.

21. The network device of claim 20, wherein the first type of message is a SIP 200 OK message and the second type of message is a SIP 481 Call/Transaction does not exist message.

22. The network device of claim 17, wherein the session refresher is configured to send a negotiation message to the refreshes indicating the refresh method is supported, and wherein the inactive session identifier is configured to receive a response from the refreshee indicating whether the refreshee supports the refresh method.

23. The network device of claim 22, wherein the session refresher is further configured to send a message with a body if the refresh method is not supported.

24. The network device of claim 17, wherein the refresh message includes a header consisting of a message field, From field, TO field, call-ID field, and Cseq field as defined in SIP.

25. A network device configured to refresh a session, the network device comprising:

a session refreshee configured to;

receive a refresh message for a session from a refresher, the refresh message not including a body; and

parse the refresh message to determine the session to refresh;

a response generator configured to;

generate a response message, the response message not including a body; and

send a response message, the response message indicating a result of the refresh performed for the session.

26. The network device of claim 25, wherein the refresh message and/or the response message include a reduced header that only includes mandatory header fields as defined in SIP.

27. The network device of claim 25, wherein the response message is a first type of message if the session is active and a second type of message if the session is inactive.

28. The network device of claim 27, wherein the first type of message is a SIP 200 OK message and the second type of message is a SIP 481 Call/Transaction does not exist message.

29. The network device of claim 25, wherein the body does not include an SDP.

30. The network device of claim 25, wherein the session refreshee is configured to receive a negotiation message from the refresher indicating the refresh method is supported, and wherein the response generator is configured to send a response from the refreshee indicating whether the refresh method is supported.

31. The network device of claim 30, wherein the session refreshee is configured to receive a message with the body if the refresh method is not supported.

32. The network device of claim 25, wherein the refresh message includes a header consisting of a message field, From field, TO field, call-ID field, and Cseq field as defined in SIP.

33. An apparatus configured to refresh a session, the apparatus comprising:

means for generating a refresh message to initiate a refresh of a session at a refreshee, the refresh message not including a body;

means for sending a refresh message to the refreshee;

means for receiving a response message for the refresh that has been performed for the session; and

means for determining if the session is active or inactive based on the received response message.

34. An apparatus configured to refresh a session, the apparatus comprising:

means for receiving a refresh message for a session from a refresher, the refresh message not including a body;

means for parsing the refresh message to determine the session to refresh;

means for generating a response message, the response message not including a body; and

means for sending a response message, the response message indicating a result of the refresh performed for the session.