Interworking of multimedia and telephony equipment

1. A method for associating multimedia clients with telephony devices comprising:

a) receiving from a first telephony device having a first telephone number a second telephone number associated with a second telephony device to initiate a voice call from the first telephony device to the second telephony device;

b) determining if the first telephony device is associated with a first multimedia client;

c) obtaining a first address associated with the first multimedia client from a first service node based on the first telephone number;

d) determining if the second telephony device is supported by the first service node;

e) if the second telephony device is not supported by the first service node, routing call signaling for the voice call to a first call server, which controls a trunk gateway interfacing with a packet network; and

f) establishing a voice connection for the voice call to the trunk gateway.

2. The method of claim 1 further comprising routing the call signaling for the voice call to a public switched telephone network if the first telephony device is not associated with the first multimedia device.

3. The method of claim 1 further comprising when the second telephony device is supported by the first service node:

a) determining if the second telephony device is associated with a second multimedia client;

b) routing the call signaling for the voice call to the first call server when the second telephony device is associated with the second multimedia client; and

c) routing the call signaling for the voice call to a public switched telephone network if the second telephony device is not associated with the second multimedia device.

4. The method of claim 3 further comprising accessing a local number portability server to determine if the second telephony device is associated with the second multimedia client.

5. The method of claim 1 further comprising:

a) receiving the first telephone number and the first address for the first multimedia client associated with the first telephony device at a second call server supporting the second telephony device;

b) sending the second telephone number, first address, and first telephone number from the second call server to a second service node, which will identify a second address for a second multimedia client associated with the second telephony device based on the second telephone number; and

c) sending the first address from the second service node to the second multimedia client using the second address.

6. The method of claim 5 further comprising sending the second address from the second multimedia client to the first multimedia client using the first address, such that either of the first or second multimedia clients can initiate a media session with the other.

7. The method of claim 1 where the second telephone number is associated with a plurality of telephony devices, including the second telephony device, supported by a public branch exchange (PBX), the second telephony device having an extension number, the method further comprising:

a) receiving the first telephone number and the first address for the first multimedia client associated with the first telephony device at a second call server associated with the PBX;

b) connecting the voice call to an attendant, which will recover the extension number for the second telephony device;

c) sending the extension number, first address, and first telephone number from the second call server to a second service node, which will identify a second address for a second multimedia client associated with the second telephony device based on the extension number; and

d) sending the first address from the second service node to the second multimedia client using the second address.

8. The method of claim 7 further comprising sending the second address from the second multimedia client to the first multimedia client using the first address, such that either of the first or second multimedia clients can initiate a media session with the other.

9. The method of claim 7 further comprising establishing a voice connection between the first and second telephony devices.

10. The method of claim 7 wherein the second call server is integrated with the PBX.

11. The method of claim 7 wherein the second call server is separate from the PBX.

12. A method for associating multimedia clients with telephony devices comprising:

a) receiving from a first telephony device having a first telephone number a second telephone number associated with a second telephony device to initiate a voice call from the first telephony device to the second telephony device;

b) routing call signaling for the voice call to a telephony switch supporting the second telephony device;

c) determining if the first telephony device is associated with a first multimedia client;

d) determining if the second telephony device is supported by a service node supporting the first telephony device;

e) if the second telephony device is supported by the service node, sending the first and second telephone numbers from the telephony switch to the service node, which will provide a first address associated with a first multimedia client based on the first telephone number and a second address for a second multimedia client based on the second telephone number; and

f) sending the first address to the second multimedia client using the second address.

13. The method of claim 12 further comprising establishing a voice connection between the first and second telephony devices.

14. The method of claim 12 further comprising accessing a local number portability server to determine if the second telephony device is associated with the second multimedia client prior to routing the call signaling for the voice call to the telephony switch.

15. A method for associating multimedia clients with telephony devices comprising:

a) routing a voice call from a first telephony device associated with a first multimedia client to a second telephony device associated with a second multimedia client, the first telephony device associated with a first telephone number and the second telephony device associated with a second telephone number;

b) obtaining a first address associated with the first multimedia client from a first service node based on the first telephone number;

c) determining if the second telephony device is supported by the first service node;

d) if the second telephony device is not supported by the first service node, sending a second service node the first address and the second telephone number;

e) identifying a second address associated with the second multimedia client at the second service node based on the second telephone number; and

f) sending the first address to the second multimedia client using the second address.

16. The method of claim 15 further comprising sending the second address from the second multimedia client to the first multimedia client using the first address, such that either of the first or second multimedia clients can initiate a media session with the other.

17. The method of claim 15 further comprising establishing a voice connection between the first and second telephony devices.

18. The method of claim 17 further comprising accessing a local number portability server to determine if the second telephony device is associated with the second multimedia client.

19. The method of claim 15 further comprising determining if the first telephony device is associated with the first multimedia client.

20. The method of claim 19 further comprising routing call signaling for the voice call to a first call server if the first telephony device is associated with the first multimedia client.

21. The method of claim 20 further comprising routing the call signaling for the voice call to a public switched telephone network if the first telephony device is not associated with the first multimedia client.

22. The method of claim 15 further comprising determining if the second telephony device is supported by the first service node and routing call signaling for the voice call to a first call server when the second telephony device is not supported by the first service node.

23. The method of claim 22 further comprising when the second telephony device is supported by the first service node:

a) determining if the second telephony device is associated with the second multimedia client;

b) routing the call signaling for the voice call to the first call server when the second telephony device is associated with the second multimedia client; and

c) routing the call signaling for the voice call to a public switched telephone network if the second telephony device is not associated with the second multimedia client.

24. A system for associating multimedia clients with telephony devices comprising a telephony switch supporting a first telephony device and adapted to:

a) receive from the first telephony device having a first telephone number a second telephone number associated with a second telephony device to initiate a voice call from the first telephony device to the second telephony device;

b) determine whether the first telephony device is associated with a first multimedia client;

c) obtain a first address associated with the first multimedia client from a first service node based on the first telephone number;

d) determine if the second telephony device is supported by the first service node;

e) if the second telephony device is not supported by the first service node, route call signaling for the voice call to a first call server, which controls a trunk gateway interfacing with a packet network; and

f) establish a voice connection for the voice call to the trunk gateway.

25. The system of claim 24 wherein the telephony switch is further adapted to route the call signaling for the voice call to a public switched telephone network if the first telephony device is not associated with the first multimedia client.

26. The system of claim 24 wherein when the second telephony device is supported by the first service node, the telephony switch is further adapted to:

a) determine if the second telephony device is associated with the second multimedia client;

b) route the call signaling for the voice call to the first call server when the second telephony device is associated with the second multimedia client; and

c) route the call signaling for the voice call to a public switched telephone network if the second telephony device is not associated with the second multimedia client.

27. The system of claim 26 further comprising accessing a local number portability server to determine if the second telephony device is associated with the second multimedia client.

28. The method of claim 1 , wherein the first call server is a SIP call server.

29. The method of claim 5 , wherein the second call server is a SIP call server.

30. The method of claim 20 , wherein the first call server is a SIP call server.

31. The system of claim 24 , wherein the first call server is a SIP call server.

32. The method of claim 1 , wherein the receiving step occurs at a telephony switch supporting the first telephony device, and steps (b)-(f) are performed at least in part by the telephony switch.

33. The method of claim 12 , wherein the receiving step occurs at a telephony switch supporting the first telephony device, and steps (b)-(f) are performed at least in part by the telephony switch.

34. The method of claim 15 , wherein steps (a)-(f) are performed at least in part by a telephony switch.