DYNAMIC SIP MAX-HOP SETUP FOR IMS

• US 20100316048A1
• Filed: 06/10/2009
• Published: 12/16/2010
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Inventors: Reyes, Emerando M. Delos, Ait-Ameur, Samir
• Granted Patent: US 8,098,594 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways

Abstract

A device forwards in a network, a session setup request from an originating user device toward a destination user device and intercepts a too many hops error message from a network element to the originating user device. The device also automatically sends, in response to the error message, a search request message to determine a correct number of hops from the originating user device to the destination user device and resets a Max-Forwards value for the session setup request based on the determined correct number of hops. The session setup request with the determined correct number of hops may be resent on behalf of the originating device without the too may hops error ever reaching the originating device.

Claims

1. A computer device-implemented method, comprising:

forwarding, in a Session Initiation Protocol (SIP) network and by the computer device, a session setup request from an originating user device toward a destination user device;

intercepting, by the computer device, a too many hops error message from a network element to the originating user device;

automatically sending, in response to the intercepting and by the computer device, a search request message to determine a correct number of hops from the originating user device to the destination user device;

resetting, by the computer device, a Max-Forwards value for the session setup request based on the determined correct number of hops; and

resending, by the computer device, the session setup request, with the determined correct number of hops, on behalf of the originating device.

2. The computer device-implemented method of claim 1, further comprising:

receiving a result of the search request message, the result indicating the correct number of hops to the destination user device;

associating the result with an identifier for the destination user device; and

storing the result of the search request message with the associated identifier for the destination user device.

3. The computer device-implemented method of claim 2, further comprising:

receiving another session setup request for the destination user device;

comparing a Max-Forwards value in the other session setup request to the stored result of the search request message; and

resetting the Max-Forwards value for the other session setup request to the stored result of the search request message if the Max-Forwards value in the other session setup request is different than the stored result of the search request message.

4. The computer device-implemented method of claim 2, further comprising:

receiving another session setup request for the destination user device; and

resetting the Max-Forwards value for the other session setup request to the stored result of the search request message.

5. The computer device-implemented method of claim 1, where the network comprises an Internet Protocol (IP) Multimedia Subsystem (IMS) network.

6. The computer device-implemented method of claim 5, further comprising:

receiving, at a first node in the network, the session setup request from the originating user device toward the destination user device.

7. The computer device-implemented method of claim 1, where the stored result of the search request message is included in a data structure with stored results of other search request messages.

8. The computer device-implemented method of claim 1, further comprising:

periodically updating the stored result of the search request message.

9. The computer device-implemented method of claim 1, further comprising:

identifying an optimal path for the session setup request;

associating the optimal path with an identifier for the destination user device; and

storing the optimal path with the associated identifier for the destination user device.

10. A method, comprising:

receiving, at a network element in a network, a session setup request from an originating user device toward a destination user device;

comparing, by the network element, a Max-Forwards value in the session setup request to a stored Max-Forwards value associated with an indicator for the destination user device;

resetting, by the network element, the Max-Forwards value for the session setup request if the Max-Forwards value is different than the stored Max-Forwards value associated with an indicator for the destination user device; and

forwarding, by the network element, the session setup request to a next hop in the network.

11. The method of claim 10, where the network comprises an Internet Protocol (IP) Multimedia Subsystem (IMS) network.

12. The method of claim 10, further comprising:

receiving, from the next hop, a too many hops error message to the originating user device;

sending, in response to the receiving, a search request message to determine a correct number of hops from the originating user device to the destination user device; and

updating the stored Max-Forwards value associated with the indicator for the destination user device.

13. The method of claim 10, further comprising:

sending a periodic ping request to update the stored Max-Forwards value associated with the indicator for the destination user device.

14. A device, comprising:

a memory to store a plurality of instructions; and

a processor to execute instructions in the memory to;

receive a session setup request from an originating user device,

forward, over a network, a session setup request toward a destination user device,

intercept a response to the originating user device, the response including a too many hops error message,

send, over the network and in response to the intercepted response, a search request message to determine a correct number of hops from the originating user device to the destination user device,

reset a Max-Forwards value for the session setup request based on the determined correct number of hops, and

resend the session setup request with the rest Max-Forwards value on behalf of the originating device.

15. The method of claim 14, where the processor is further to:

receive a result of the search request message, the result indicating the correct number of hops to the destination user device,

associate the result with an identifier for the destination user device, and

store the result of the search request message with the associated identifier for the destination user device.

16. The method of claim 14, where the processor is further to:

receive another session setup request for the destination user device,

compare a Max-Forwards value in the other session setup request to the stored result of the search request message, and

reset the Max-Forwards value for the other session setup request if the Max-Forwards value in the other session setup request is different than the stored result of the search request message.

17. The method of claim 14, where the network comprises an Internet Protocol (IP) Multimedia Subsystem (IMS) network.

18. The method of claim 14, where the processor is further to:

periodically update the stored result of the search request message.

19. A system comprising:

means for receiving a Session Initiation Protocol (SIP) session setup request from an originating user device;

means for forwarding the SIP session setup request toward a destination user device;

means for intercepting a SIP response, including a too many hops error message, from a network element to the originating user device;

means for automatically sending, in response to the SIP response, a request message to determine the correct number of hops from the originating user device to the destination user device;

means for receiving a reply to identify a correct number of hops for an optimal path to the destination user device;

means for resetting a max hop count value for the session setup request based on the determined correct number of hops; and

means for resending the session setup request, toward the destination user device, with the determined correct number of hops on behalf of the originating device.

20. The method of claim 19, where the network comprises an Internet Protocol (IP) Multimedia Subsystem (IMS) network.