Method and apparatus for call routing via gateway brokering

• US 20060034270A1
• Filed: 08/10/2004
• Published: 02/16/2006
• Est. Priority Date: 08/10/2004
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Inventors: Murakami, Kazutaka, Haase, Oliver
• Granted Patent: US 7,558,254 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 61/4557 Directories for hybrid networks, e.g. including telephone numbers
• CPC Class Codes: H04L 65/103 in the network
• CPC Class Codes: H04L 65/104 in the network
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04M 7/128 Details of addressing, directories or routing tables
• CPC Class Codes: H04M 7/1285 Details of finding and selecting a gateway for a particular call
• CPC Class Codes: Y10S 379/90 Internet, e.g. Internet phone, webphone, internet-based telephony

Abstract

Method and apparatus for routing telephone calls across different types of networks includes means for and steps of determining a destination IP address of a new call according to initial conditions established in a first network, determining a destination gateway (gateway brokering) based on the destination IP address, the initial conditions and a gateway selection policy, providing routing information of the destination gateway to the first network and completing the new call set up via messages received from the gateway brokering step. The initial conditions in the first network are established by determining if a callee is part of an IP network or part of a CS network and converting the callee phone number to an SIP URL if the callee is part of the IP network. Such determination is made by recognizing a prefix identifying an IP destination in the callee phone number.

Claims

1. A method, comprising the steps of:

determining a destination IP address of a new call according to initial conditions established in a first network for gateway brokering of the new call from the first network to a second network;

determining a destination gateway (gateway brokering) based on the destination IP address, said initial conditions and a gateway selection policy;

providing routing information of the destination gateway to the first network; and

completing the new call set up via messages received from the gateway brokering step.

2. The method of claim 1 wherein the initial conditions in the first network are established by determining if a callee is part of an IP network or part of a CS network and converting the callee phone number to an SIP URL if the callee is part of the IP network.

3. The method of claim 2 wherein the step of determining if the callee is part of an IP network or part of a CS network is performed by recognizing a prefix identifying an IP destination in the callee phone number.

4. The method of claim 2 wherein the callee phone number is converted to an SIP URL by accessing a server in the CS network.

5. The method of claim 1 wherein the step of determining a destination IP address based on initial conditions further comprises interrogating a location server in the second network where the new call is to be terminated.

6. The method of claim 5 wherein the interrogation and subsequent determination is conducted by an SDHLR subcomponent.

7. The method of claim 5 wherein the interrogation and determination is made by a location server in the second network where the new call is to be terminated via an HLR and translator subcomponents.

8. The method of claim 1 wherein the step of determining a destination gateway based on destination IP address, initial conditions and gateway selection policy further comprises selecting one of a plurality telephone numbers assigned to one of a plurality of gateways in the IP network.

9. The method of claim 1 where the step of providing information of the destination gateway further comprises sending information to components in the first network that are in communication with gateways in the second network.

10. A computer readable medium containing a program which, when executed, performs an operation of gateway brokering new telephone calls from a first network to a second network comprising the steps of:

determining a destination IP address for the new call based on said initial conditions in the first network;

determining a destination gateway (gateway brokering) based on the destination IP address, said initial conditions and a gateway selection policy;

providing routing information of the destination gateway to the first network; and

completing the new call set up via messages received from the gateway brokering step.

11. The method of claim 10 wherein the initial conditions in the first network are established by determining if a callee is part of an IP network or part of a CS network and converting the callee phone number to an SIP URL if the callee is part of the IP network.

12. The method of claim 11 wherein the step of determining if the callee is part of an IP network or part of a CS network is performed by recognizing a prefix identifying an IP destination in the callee phone number.

13. The method of claim 11 wherein the callee phone number is converted to an SIP URL by accessing a server in the CS network.

14. The method of claim 10 wherein the step of determining a destination IP address based on initial conditions further comprises interrogating a location server in the second network where the new call is to be terminated.

15. The method of claim 14 wherein the interrogation and subsequent determination is conducted by an SDHLR subcomponent.

16. The method of claim 14 wherein the interrogation and determination is made by a location server in the second network where the new call is to be terminated via an HLR and translator subcomponents.

17. The method of claim 10 wherein the step of determining a destination gateway based on destination IP address, initial conditions and network policy further comprises selecting one of a plurality telephone numbers assigned to one of a plurality of gateways in the IP network.

18. The method of claim 10 where the step of providing information of the destination gateway further comprises sending information to components in the first network that are in communication with gateways in the second network.

19. Apparatus comprising:

means for maintaining a pool of telephone numbers assigned to a plurality of telephony gateways;

means for determining an optimal gateway of the plurality of telephony gateways based on at least a terminating IP address of a callee;

means for requesting a telephone number from the optimal gateway; and

means for releasing said telephone number from a mapping to the terminating IP address.

20. The apparatus of claim 19 wherein the means for maintaining a pool of telephone numbers assigned to a plurality of telephony gateways is a temporary SIP gateway number (TSGN) Manager.

21. The apparatus of claim 20 wherein the TSGN Manager randomly selects a telephone number from the optimal gateway to be mapped to the terminating IP address.

22. The apparatus of claim 19 wherein the means for determining an optimal gateway of the plurality of telephony gateways based on at least a terminating IP address of a callee further comprises a TRIP server.

23. The apparatus of claim 19 wherein the means for requesting a telephone number from the optimal gateway further comprises a TSGN Requestor.

24. The apparatus of claim 19 wherein the means for releasing said telephone number from a mapping to the terminating IP address is a TSGN Resolver.