Method and system for dynamic gateway selection in an IP telephony network

• US 8,743,892 B2
• Filed: 07/13/2004
• Issued: 06/03/2014
• Est. Priority Date: 11/08/1999
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Business Global LLC (Verizon Communications Inc.)
• Inventors: Gallant, John K., Donovan, Steven R.
• Primary Examiner(s): MURPHY, RHONDA L
• Application Number:
  US10/889,051
• Publication Number:
  US 20040258239A1
• Time in Patent Office: 3,612 Days
• Field of Search: 370216-217, 370219-221, 370/242, 370/252, 370352-356, 370400-401, 709227-228, 709/238
• US Class Current: 370/401
• CPC Class Codes: H04L 2012/5667 IP over ATM
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 65/103 in the network
• CPC Class Codes: H04L 65/104 in the network
• CPC Class Codes: H04L 65/1043 Gateway controllers, e.g. media gateway control protocol [MGCP] controllers
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 7/1285 Details of finding and selecting a gateway for a particular call

Abstract

A method and system for dynamically selecting a destination gateway to complete a call over a path supported at least in part by an IP telephony network and a public switched telephone network. The method and system further provide for dynamically detecting available gateways, dynamically removing failed and/or unavailable gateways, and automatically recovering failed and/or unavailable gateways after a predetermined period of time. A method is also provided for detecting available destination gateways using a ping method, where a message is transmitted to a plurality of destination gateways on a one-by-one basis to ascertain the availability status of each destination gateway.

Claims

1. A system for selecting a destination gateway in a network, the system comprising:

a proxy server operatively connected to an ingress gateway and a plurality of destination gateways; and

a redirect server operatively connected to the proxy server,

wherein the proxy server is configured to receive a call setup request from the ingress gateway and request routing information relating to the call setup request from the redirect server,

wherein the redirect server is configured to;

send a communication to each of the plurality of destination gateways,

record, in a table, information identifying each destination gateway for which a response to the communication was received as being in-service,

record, in the table, information identifying each destination gateway for which a response to the communication was not received as being unavailable,

retrieve the routing information from the table, and

forward the routing information to the proxy server, the routing information including a listing of destination gateways that are recorded in the table as being in-service and are capable of handling the call setup request, and

wherein the proxy server is configured to forward the call setup request to at least one of the destination gateways listed in the routing information.

2. The system of claim 1, wherein the proxy server is further configured to receive a success response to the call setup request from the at least one of the destination gateways and forward the success response to the ingress gateway to facilitate call setup.

3. The system of claim 2, wherein the proxy server is further configured to forward the call setup message successively to multiple destination gateways if the success response is not received.

4. The system of claim 2, wherein the proxy server is further configured to:

record, for the at least one of the destination gateways, a destination gateway status as unavailable if the success response from the at least one of the destination gateways is not received within a predetermined time, and

record, for the at least one of the destination gatways, a destination gateway status as unavailable if a response from the at least one of the destination gateways indicates that the at least one of the destination gateways is unavailable.

5. The system of claim 2, wherein the proxy server is further configured to forward a request failure response to the ingress gateway if the success response is not received.

6. The system of claim 1, wherein the redirect server is further configured to pass a request failure response to the proxy server based on the request for routing information when a destination gateway recorded as being in-service and capable of handling the call setup request is not identified.

7. The system of claim 6, wherein the proxy server is further configured to forward the request failure response to the ingress gateway.

8. The system of claim 1, wherein the redirect server is further configured to store the routing information and destination gateway status information, associated with the plurality of destination gateways, in the table.

9. The system of claim 1, wherein the proxy server comprises a Session Initiation Protocol (SIP) proxy server.

10. The system of claim 1, wherein the proxy server comprises an H.323 gatekeeper.

11. A system for selecting a destination gateway in a network, the system comprising:

a proxy server operatively connected to an ingress gateway and a plurality of destination gateways; and

a redirect server operatively connected to the proxy server,

wherein the proxy server is configured to receive a call setup request from the ingress gateway and request routing information relating to the call setup request from the redirect server,

wherein the redirect server is configured to;

send a message to each of the plurality of destination gateways,

receive a response from at least one of the plurality of destination gateways,

record information identifying each destination gateway for which a response was received as being in-service,

record information identifying each destination gateway for which a response was not received as being unavailable,

retrieve the routing information, and

forward the routing information to the proxy server, the routing information including a listing of one or more destination gateways capable of handling the call setup request and recorded as being in-service, and

wherein the proxy server is configured to forward a response request message to at least one of the one or more destination gateways listed in the routing information.

12. The system of claim 11, wherein the proxy server is further configured to receive an acknowledgement response from one of the plurality of destination gateways, the response indicating that the one of the plurality of destination gateways is available.

13. The system of claim 12, wherein the proxy server is further configured to forward a request message to each of the one or more destination gateways and receive an acknowledgment response from each of the one or more destination gateways.

14. The system of claim 12, wherein the proxy server is further configured to wait for the acknowledgement response from the one of the plurality of destination gateways for a predetermined period of time.

15. The system of claim 14, wherein the proxy server is further configured to record information identifying the one of the plurality of destination gateways as unavailable if the acknowledgement response is not received within the predetermined period of time.

16. A method for selecting a destination gateway in a network, the method comprising:

receiving a call setup request from an ingress gateway;

requesting routing information relating to the call setup request from a redirect server;

sending a communication to each of a plurality of destination gateways;

recording information identifying each destination gateway for which a response to the communication was received as being in-service;

recording information identifying each destination gateway for which a response to the communication was not received as being unavailable;

receiving routing information from the redirect server when routing information is available, the routing information including a listing of one or more destination gateways capable of handling the call setup request and recorded as being in-service;

forwarding the call setup request to at least one of the one or more destination gateways listed in the routing information;

receiving a request failure response from the redirect server when routing information is not available, the request failure response indicating that no destination gateways are available to handle the call setup request; and

forwarding the request failure response to the ingress gateway.

17. The method of claim 16, further comprising:

receiving a success response to the call setup request from the at least one of the one or more destination gateways; and

forwarding the success response to the ingress gateway to facilitate call setup.

18. The method of claim 17, further comprising:

forwarding the call setup to request to another destination gateway listed in the routing information when the success response is not received from the at least one of the one or more destination gateways.

19. A method for selecting a destination gateway in a network, the method comprising:

receiving a call setup request from an ingress gateway;

requesting routing information relating to the call setup request from a redirect server;

sending a communication to each of a plurality of destination gateways;

recording information identifying each destination gateway for which a response to the communication was received in a predetermined amount of time as being in-service;

recording information identifying each destination gateway for which a response to the communication was not received in the predetermined amount of time as being unavailable;

receiving routing information from the redirect server when routing information is available, the routing information including a listing of one or more destination gateways capable of handling the call setup request and recorded as being in-service; and

forwarding a response request to at least one of the one or more destination gateways listed in the routing information.

20. The method of claim 19, further comprising:

receiving an acknowledgement response to the communication from a first destination gateway, the response indicating that the first destination gateway is in-service.

21. A system for selecting a destination gateway in a network, the system comprising:

a server operatively connected to an ingress gateway and a plurality of destination gateways, the server being configured to;

receive a call setup request from the ingress gateway,

retrieve routing information relating to the call setup request, the routing information including a listing of one or more destination gateways, of the plurality of destination gateways, capable of handling the call setup request, and

forward the call setup request to at least one of the one or more destination gateways listed in the routing information,

wherein if a destination gateway status, of a destination gateway of the plurality of destination gateways, is recorded as out-of-service in a gateway information table and a time value associated with the recorded status is greater than a current time, an address of the destination gateway is not added to a routing list included in the routing information, and

wherein if the destination gateway status is recorded as out-of-service in the gateway information table and a time value associated with the recorded status is less than or equal to a current time, the address of the destination gateway is added to a routing list included in the routing information and recorded as in-service.

22. The system of claim 21, wherein the server is further configured to receive a success response to the call setup request from the at least one of the one or more destination gateways and forward the success response to the ingress gateway to facilitate call setup.

23. The system of claim 22, wherein the server is further configured to forward the call setup request to another destination gateway if the success response is not received.

24. The system of claim 22, wherein the server is further configured to:

record, for the at least one of the one or more destination gateways, a destination gateway status as unavailable if the success response from the at least one of the one or more destination gateways is not received within a predetermined time, and

record, for the at least one of the one or more destination gateways, a destination gateway status as unavailable if a response from the at least one of the one or more destination gateways indicates the destination gateway is unavailable.

25. The system of claim 22, wherein the server is further configured to forward a request failure response to the ingress gateway if the success response is not received.

26. The system of claim 21, wherein the server is further configured to forward a request failure response to the ingress gateway if no routing information relating to the call setup request is retrieved.

27. The system of claim 21, wherein the server is further configured to store the routing information and destination gateway status information, associated with the plurality of destination gateways, in a gateway information table.