METHODS, SYSTEMS, AND COMPUTER PROGRAM PRODUCTS FOR USING SIGNALING SYSTEM 7 (SS7) SUBSYSTEM NUMBERS TO ROUTE MESSAGES TO SESSION INITIATION PROTOCOL (SIP) NODES

1 . A method for using SS7 subsystem numbers to route messages to session initiation protocol (SIP) nodes, the method comprising:

(a) receiving an SS7 message;

(b) generating a SIP message based on the SS7 message;

(c) identifying a subsystem number associated with the SS7 message;

(d) identifying, based on the subsystem number, a destination SIP node for the SIP message; and

(e) forwarding the SIP message to the SIP node.

2 . The method of claim 1 wherein identifying a subsystem number associated with the SS7 message includes extracting the subsystem number from the SS7 message.

3 . The method of claim 1 wherein identifying a subsystem number associated with the SS7 message includes performing a global title translation for the SS7 message.

4 . The method of claim 1 wherein performing steps (a)-(e) includes performing steps (a)-(e) using a signaling transfer point and an SS7/SIP gateway external to the signal transfer point.

5 . The method of claim 1 wherein performing steps (a)-(e) including performing steps (a)-(e) using a signal transfer point and an SS7/SIP gateway located internal to the signal transfer point.

6 . The method of claim 1 comprising assigning a plurality of different subsystem numbers to a plurality of different SIP nodes.

7 . The method of claim 6 comprising assigning at least one subsystem number to a group of SIP nodes for load sharing purposes.

8 . A system for using SS7 subsystem numbers to route messages to session initiation protocol (SIP) nodes, the system comprising:

(a) a communication module for receiving an SS7 message; and

(b) a gateway function configured to:

(i) generate a SIP message based on the SS7 message; and

(ii) identify a subsystem number associated with the SS7 message; and

(c) a distribution function configured to:

(i) identify, based on the subsystem number, a destination SIP node for the SIP message; and

(ii) forward the SIP message to the SIP node.

9 . The system of claim 8 wherein the gateway function is configured to extract the subsystem number from the SS7 message.

10 . The system of claim 8 comprising a global title translation function operable to perform a global title translation for the SS7 message and determine the subsystem number.

11 . The system of claim 8 comprising a signaling transfer point (STP) and an SS7/SIP gateway (SSG) external to the signal transfer point, wherein the communication module is a component of the STP and the gateway function is a component of the SSG.

12 . The system of claim 8 comprising a signaling transfer point (STP) and an SS7/SIP gateway (SSG) located internal to the signal transfer point, wherein the communication module is a component of the STP and the gateway function is a component of the SSG.

13 . The system of claim 8 wherein the gateway function is configured to assign a plurality of different subsystem numbers to a plurality of different SIP nodes.

14 . The system of claim 13 wherein the gateway function is configured to assign at least one subsystem number to a group of SIP nodes for load sharing purposes.

15 . A system for distributing an SS7 message to one of a plurality of SS7/session initiation protocol gateways (SSGs), the method comprising:

(a) a communication module for receiving an SS7 message;

(b) a global title translation function for performing global title translation of the SS7 message to identify a subsystem number for the SS7 message; and

(c) a distribution function for selecting an SSG from a plurality of SSGs based on the subsystem number, and for forwarding the SS7 message to the selected SSG.

16 . The system of claim 15 wherein the SSG is configured to generate a SIP message corresponding to the SS7 message and to forward the SIP message to a SIP destination.

17 . The system of claim 16 comprising a SIP node for generating a SIP message including a subsystem number that identifies the SSG in the SIP message.

18 . The system of claim 17 comprising a distribution function for identifying at least one second SIP message as being associated with the same transaction as the first SIP message using the subsystem number that identifies the SSG.