METHODS, SYSTEMS, AND COMPUTER READABLE MEDIA FOR REGULATING NETWORK ADDRESS TRANSLATOR (NAT) AND FIREWALL PINHOLE PRESERVATION TRAFFIC IN A SESSION INITIATION PROTOCOL (SIP) NETWORK

• US 20100161809A1
• Filed: 12/14/2009
• Published: 06/24/2010
• Est. Priority Date: 12/12/2008
• Status: Active Grant

• Current Assignee: Tekelec
• Original Assignee: Tekelec
• Inventors: Sparks, Robert J., Campbell, Ben Allen, Deo, Ajay P., Roach, Adam B.
• Granted Patent: US 8,090,850 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• CPC Class Codes: H04L 61/2567 for reachability, e.g. inquiring the address of a correspondent behind a NAT server
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 65/1073 Registration or de-registration
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]

Abstract

Methods, systems, and computer readable media for regulating pinhole preservation traffic generated or received by firewall or network address translator (NAT) session initiation protocol (SIP) user agent clients (UACs) are disclosed. One method includes, maintaining a list of contact information for a plurality of SIP UACs registering from behind at least one of a firewall and a NAT. The method further includes iterating through the list to generate SIP messages to the different UACs such that the SIP messages to the different UACs are spaced at substantially regular intervals with respect to each other, wherein the SIP messages to the different UACs trigger responses from the UACs such that the responses are spaced at substantially regular intervals with respect each other.

Claims

1. A method for regulating network address translator (NAT) or firewall pinhole preservation traffic generated by session initiation protocol (SIP) user agent clients (UACs), the method comprising:

at a SIP entity including one or more processors;

maintaining a list of contact information for a plurality of SIP UACs registering from behind at least one of a firewall and a NAT;

iterating through the list to generate and send SIP messages to the different UACs such that the SIP messages to the different UACs are spaced at substantially regular intervals with respect to each other, wherein the SIP messages to the different UACs trigger responses from the UACs such that the responses are spaced at substantially regular intervals with respect each other.

2. The method of claim 1 wherein maintaining a list of contact information includes storing a minimum amount of state consisting of a source internet protocol (IP) address and a port for each UAC.

3. The method of claim 1 wherein the SIP messages sent to the UACs are configured such that the responses can be identified and discarded below a SIP transaction layer in a SIP processing stack.

4. The method of claim 1 wherein the SIP messages sent to the UACs comprise SIP Options messages.

5. The method of claim 1 wherein the SIP messages each include a branch parameter identifying the message as being associated with pinhole preservation.

6. The method of claim 1 wherein the SIP messages sent to the UACs are sent at intervals sufficiently short to ensure pinhole preservation.

7. The method of claim 1 wherein the substantial regular intervals of the SIP messages to the different UACs are determined by an algorithm that determines the intervals based on a number of registered users and a predetermined time period.

8. The method of claim 1 wherein the SIP entity comprises at a SIP proxy.

9. The method of claim 1 wherein the SIP entity comprises a session border controller (SBC).

10. The method of claim 1 comprising:

replicating the minimum amount of state for at least a portion of the list of registrations from the SIP entity to a geographically diverse standby SIP entity.

11. A system for regulating network address translator (NAT) or firewall pinhole preservation traffic generated by session initiation protocol (SIP) user agent clients (UACs), the system comprising:

a SIP entity including one or more processors, the SIP entity comprising;

a registration store embodied in a computer readable medium accessible by the one or more processors, the registration store being configured for maintaining a list of contact information for a plurality of SIP UACs registering from behind at least one of a firewall and a NAT; and

a SIP pinhole preservation traffic regulator executable by the one or more processors for iterating through the list to generate and send SIP messages to the different UACs such that the SIP messages to the different UACs are spaced at substantially regular intervals with respect to each other, wherein the SIP messages to the different UACs trigger responses from the UACs such that the responses are spaced at substantially regular intervals with respect each other.

12. The system of claim 11 wherein maintaining a list of registrations includes storing a minimum amount of state consisting of a source internet protocol (IP) address and a port for each registration.

13. The system of claim 11 wherein the SIP messages sent to the UACs are configured such that the responses can be identified and discarded below a SIP transaction layer in a SIP processing stack.

14. The system of claim 11 wherein the SIP messages sent to the UACs comprise SIP Options messages.

15. The system of claim 11 wherein the SIP messages each include a branch parameter indentifying the message as being associated with pinhole preservation.

16. The system of claim 11 comprising:

replicating the minimum amount of state for at least a portion of the list of registrations from the SIP entity to a geographically diverse standby SIP proxy.

17. The system of claim 11 wherein the SIP entity includes a SIP proxy.

18. The system of claim 11 wherein the SIP entity includes a session border controller (SBC).

19. The system of claim 11 wherein the SIP pinhole preservation traffic regulator is configured to determine the intervals for spacing of the SIP messages based on a number of registered UACs and a predetermined time period.

20. A non-transitory computer readable medium having stored thereon computer executable instructions that when executed by a processor of a computer performs steps comprising:

at a SIP entity including one or more processors;

maintaining a list of contact information for a plurality of SIP UACs registering from behind at least one of a firewall and a NAT;

iterating through the list to generate and send SIP messages to the different UACs such that the SIP messages to the different UACs are spaced at substantially regular intervals with respect to each other, wherein the SIP messages to the different UACs trigger responses from the UACs such that the responses are spaced at substantially regular intervals with respect each other.