Arrangement for managing multiple gateway trunk groups for voice over IP networks

• US 7,248,565 B1
• Filed: 05/16/2002
• Issued: 07/24/2007
• Est. Priority Date: 05/16/2002
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Fourie, Henry Louis
• Primary Examiner(s): Rao; Seema S.
• Assistant Examiner(s): HOM, SHICK C
• Application Number:
  US10/145,906
• Time in Patent Office: 1,895 Days
• Field of Search: 370/235, 370/236, 370/352, 370/353, 370/537, 370/395.3, 370/395.31, 370/395.42, 370/395.52, 370/401, 370/402, 379/240, 379/290, 379/241, 379/268, 379/333, 379/337, 379/220.1, 709/229, 709/244
• US Class Current: 370/235
• CPC Class Codes: H04M 7/1255 where the switching fabric and the switching logic are decomposed such as in Media Gateway Control

Abstract

An IP-based node in communication with IP-based gateway devices is configured for executing circuit selection for a prescribed trunk group having multiple sets of connected trunk groups, the multiple sets of connected trunk groups managed by the respective IP-based gateway devices. The prescribed trunk group is configured for connecting with a two-way trunk group of a switch, for example a PSTN-based switch, having substantially more circuits than any one of the multiple sets of connected trunk groups for the IP-based gateway devices. The IP-based node executes circuit selection at least based on a first message, received from one of the IP-based gateway devices via an IP connection and specifying circuit availability for at least a portion of the corresponding set of connected trunk groups. The IP-based node outputs to the one IP-based gateway device an IP-based selection message specifying a selected circuit within the corresponding set of connected trunk groups, enabling the one IP-based gateway device to select the selected circuit for communication with the switch based on the IP-based selection message.

Claims

1. A method in an Internet Protocol (IP)-based node, the method including:

establishing a prescribed trunk group having multiple sets of connected trunk groups coupled to respective IP-based gateway devices, the establishing including storing trunk group entries within a table, each trunk group entry specifying an address for one of the IP-based gateway devices and an identified one of the connected trunk groups from the corresponding set of connected trunk groups;

selecting a circuit from a selected one of the connected trunk groups for connection with a switch having a peer trunk group interfacing with the prescribed trunk group; and

outputting an IP-based selection message, identifying the selected circuit for the connection with the switch, to the corresponding IP-based gateway device configured for controlling the selected one connected trunk group.

2. The method of claim 1, further comprising receiving an IP-based status message from one of the IP-based gateway devices that includes status information for circuits of an identified one of the corresponding connected trunk groups, the storing including storing, for each trunk group entry identifying the identified one connected trunk group, a circuit identifier for a corresponding circuit unique to the corresponding identified one connected trunk group, and a service status indicator specifying whether the corresponding circuit is in-service.

3. The method of claim 2, wherein the storing of trunk group entries further includes parsing a circuit service status bit map, within the status information of the received IP-based status message and that specifies a status for each corresponding circuit of the identified one connected trunk group, for the service status indicator.

4. The method of claim 2, wherein each trunk group entry includes an allocated field value specifying whether the corresponding circuit has been allocated for a corresponding connection with the switch, the selecting including selecting the circuit based on identifying a trunk group entry having a service status indicator indicating the corresponding circuit is in-service, and an allocated field value specifying that the corresponding circuit has not been allocated.

5. The method of claim 4, further comprising:

receiving a second IP-based message from the one IP-based gateway that specifies one of the corresponding connected trunk groups, the circuit identifier for a corresponding one of the circuits, and a status of the corresponding one circuit; and

updating one of the service status indicator and the allocated field value for the trunk group entry corresponding to the one connected trunk group and circuit identifier specified in the second IP-based message.

6. The method of claim 1, wherein outputting includes specifying, within the IP-based selection message, a glare control indicator specifying a prescribed glare protocol operation to be performed by the corresponding IP-based gateway in response to detection of glare by the IP-based gateway.

7. The method of claim 6, wherein the outputting includes inserting, within the IP-based selection message, an IP address for the IP-based gateway device having the selected circuit, an identifier for the for the corresponding identified one trunk group having the selected circuit, and the corresponding circuit identifier for the selected circuit.

8. A method in an Internet Protocol (IP)-based gateway having a set of connected trunk groups for connection to at least a portion of a peer trunk group of a switch, the method comprising:

sending, to an IP-based node via an IP network, an IP-based message that specifies a trunk group identifier for a group of circuits, and status information for the group of circuits;

receiving, via the IP network, a call setup message that specifies one of the connected trunk groups, a circuit identifier, and a glare control indicator that specifies a prescribed glare arbitration;

determining whether the switch is attempting to seize the circuit specified by the circuit identifier for the one connected trunk group; and

selectively initiating an outgoing call on the circuit specified by the circuit identifier for the one connected trunk group, based on the determining whether the switch is attempting to seize the circuit and the glare control indicator.

9. The method of claim 8, wherein the selectively initiating includes determining whether the glare control indicator specifies whether the IP-based gateway has precedence for outgoing calls on the circuit, relative to incoming calls initiated by the switch.

10. The method of claim 9, wherein the selectively initiating includes initiating the outgoing call on the circuit according to Q.764 protocol according to one of a determined availability of the circuit and a determined precedence for the circuit.

11. The method of claim 8, further comprising outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a release complete message specifying a glare detection cause, based on the determining whether the switch is attempting to seize the circuit and the glare control indicator specifying the switch has precedence for the circuit.

12. The method of claim 8, further comprising:

detecting a release condition following initiating the outgoing call on the circuit by the IP-based gateway; and

outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a message specifying the release condition indicating an availability of the circuit.

13. The method of claim 8, further comprising:

detecting a changed status in at least one of the circuits; and

outputting a second IP-based message that specifies the trunk group identifier for the group of circuits including the at least one circuit, and status information that specifies at least the changed status for the one circuit.

14. An Internet Protocol (IP)-based node comprising:

a table configured for storing trunk group entries, each trunk group entry specifying an address, for an IP-based gateway device having a set of connected trunk groups, and an identified one of the connected trunk groups;

a processor configured for establishing a prescribed trunk group from multiple sets of the connected trunk groups coupled to a respective plurality of the IP-based gateway devices, the processor configured for updating one of the trunk group entries based on selecting a circuit from a corresponding selected one of the connected trunk groups for connection with a switch having a peer trunk group interfacing with the prescribed trunk group; and

an IP interface configured for outputting an IP-based selection message, generated by the processor and identifying the selected circuit for the connection with the switch, to the corresponding IP-based gateway device configured for controlling the selected one connected trunk group.

15. The node of claim 14, wherein the IP interface is configured for receiving an IP-based status message from one of the IP-based gateway devices that includes status information for circuits of an identified one of the corresponding connected trunk groups, the processor configured for storing, for each trunk group entry identifying the identified one connected trunk group, a circuit identifier for a corresponding circuit unique to the corresponding identified one connected trunk group, and a service status indicator specifying whether the corresponding circuit is in-service.

16. The node of claim 15, wherein the processor is configured for parsing a circuit service status bit map, within the status information of the received IP-based status message and that specifies a status for each corresponding circuit of the identified one connected trunk group, for the service status indicator.

17. The node of claim 15, wherein each trunk group entry includes an allocated field value specifying whether the corresponding circuit has been allocated for a corresponding connection with the switch, the processor configured for selecting the circuit based on identifying a trunk group entry having a service status indicator indicating the corresponding circuit is in-service, and an allocated field value specifying that the corresponding circuit has not been allocated.

18. The node of claim 17, wherein:

the IP interface is configured for receiving a second IP-based message from the one IP-based gateway that specifies one of the corresponding connected trunk groups, the circuit identifier for a corresponding one of the circuits, and a status of the corresponding one circuit; and

the processor is configured for updating one of the service status indicator and the allocated field value for the trunk group entry corresponding to the one connected trunk group and circuit identifier specified in the second IP-based message.

19. The node of claim 14, wherein processor is configured for specifying, within the IP-based selection message, a glare control indicator specifying a prescribed glare protocol operation to be performed by the corresponding IP-based gateway in response to detection of glare by the IP-based gateway.

20. The node of claim 19, wherein the processor is configured for inserting, within the IP-based selection message, an IP address for the IP-based gateway device having the selected circuit, an identifier for the for the corresponding identified one trunk group having the selected circuit, and the corresponding circuit identifier for the selected circuit.

21. An Internet Protocol (IP)-based gateway having a set of connected trunk groups for connection to at least a portion of a peer trunk group of a switch, the IP-based gateway further comprising:

an IP interface configured for sending, to an IP-based node via an IP network, an IP-based message that specifies a trunk group identifier for a group of circuits, and status information for the group of circuits, the IP interface configured for receiving, via the IP network, a call setup message that specifies one of the connected trunk groups, a circuit identifier, and a glare control indicator that specifies a prescribed glare arbitration; and

a processor configured for determining whether the switch is attempting to seize the circuit specified by the circuit identifier for the one connected trunk group, the processor configured for selectively initiating an outgoing call on the circuit specified by the circuit identifier for the one connected trunk group, based on whether the switch is attempting to seize the circuit and based on the glare control indicator.

22. The IP-based gateway of claim 21, wherein the processor is configured for determining whether the glare control indicator specifies whether the IP-based gateway has precedence for outgoing calls on the circuit, relative to incoming calls initiated by the switch.

23. The IP-based gateway of claim 22, wherein the processor is configured for initiating the outgoing call on the circuit according to Q.764 protocol according to one of a determined availability of the circuit and a determined precedence for the circuit.

24. The IP-based gateway of claim 21, wherein the processor is configured for generating a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a release complete message specifying a glare detection cause, based on determining the switch is attempting to seize the circuit and based on the glare control indicator specifying the switch has precedence for the circuit.

25. The IP-based gateway of claim 21, wherein the processor further is configured for:

detecting a release condition following initiating the outgoing call on the circuit by the IP-based gateway; and

generating a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a message specifying the release condition indicating an availability of the circuit.

26. The IP-based gateway of claim 21, wherein the processor further is configured for:

detecting a changed status in at least one of the circuits; and

generating a second IP-based message that specifies the trunk group identifier for the group of circuits including the at least one circuit, and status information that specifies at least the changed status for the one circuit.

27. A computer readable medium having stored thereon sequences of instructions for establishing a prescribed trunk group, the sequences of instructions including instructions for performing the steps of:

establishing a prescribed trunk group having multiple sets of connected trunk groups coupled to respective IP-based gateway devices, the establishing step including storing trunk group entries within a table, each trunk group entry specifying an address for one of the IP-based gateway devices and an identified one of the connected trunk groups from the corresponding set of connected trunk groups;

selecting a circuit from a selected one of the connected trunk groups for connection with a switch having a peer trunk group interfacing with the prescribed trunk group; and

outputting an IP-based selection message, identifying the selected circuit for the connection with the switch, to the corresponding IP-based gateway device configured for controlling the selected one connected trunk group.

28. The medium of claim 27, further comprising instructions for performing the step of receiving an IP-based status message from one of the IP-based gateway devices that includes status information for circuits of an identified one of the corresponding connected trunk groups, the storing step including storing, for each trunk group entry identifying the identified one connected trunk group, a circuit identifier for a corresponding circuit unique to the corresponding identified one connected trunk group, and a service status indicator specifying whether the corresponding circuit is in-service.

29. The medium of claim 28, wherein the storing step further includes parsing a circuit service status bit map, within the status information of the received IP-based status message and that specifies a status for each corresponding circuit of the identified one connected trunk group, for the service status indicator.

30. The medium of claim 28, wherein each trunk group entry includes an allocated field value specifying whether the corresponding circuit has been allocated for a corresponding connection with the switch, the selecting step including selecting the circuit based on identifying a trunk group entry having a service status indicator indicating the corresponding circuit is in-service, and an allocated field value specifying that the corresponding circuit has not been allocated.

31. The medium of claim 30, further comprising instructions for performing the steps of:

receiving a second IP-based message from the one IP-based gateway that specifies one of the corresponding connected trunk groups, the circuit identifier for a corresponding one of the circuits, and a status of the corresponding one circuit; and

updating one of the service status indicator and the allocated field value for the trunk group entry corresponding to the one connected trunk group and circuit identifier specified in the second IP-based message.

32. The medium of claim 27, wherein outputting step includes specifying, within the IP-based selection message, a glare control indicator specifying a prescribed glare protocol operation to be performed by the corresponding IP-based gateway in response to detection of glare by the IP-based gateway.

33. The medium of claim 32, wherein the outputting step includes inserting, within the IP-based selection message, an IP address for the IP-based gateway device having the selected circuit, an identifier for the for the corresponding identified one trunk group having the selected circuit, and the corresponding circuit identifier for the selected circuit.

34. A computer readable medium having stored thereon sequences of instructions for establishing a connection on a circuit by an Internet Protocol (IP)-based gateway having a set of connected trunk groups for connection to at least a portion of a peer trunk group of a switch, the sequences of instructions including instructions for performing the steps of:

sending, to an IP-based node via an IP network, an IP-based message that specifies a trunk group identifier for a group of circuits, and status information for the group of circuits;

receiving, via the IP network, a call setup message that specifies one of the connected trunk groups, a circuit identifier, and a glare control indicator that specifies a prescribed glare arbitration;

determining whether the switch is attempting to seize the circuit specified by the circuit identifier for the one connected trunk group; and

selectively initiating an outgoing call on the circuit specified by the circuit identifier for the one connected trunk group, based on the determining step and the glare control indicator.

35. The medium of claim 34, wherein the selectively initiating step includes determining whether the glare control indicator specifies whether the IP-based gateway has precedence for outgoing calls on the circuit, relative to incoming calls initiated by the switch.

36. The medium of claim 35, wherein the selectively initiating step includes initiating the outgoing call on the circuit according to Q.764 protocol according to one of a determined availability of the circuit and a determined precedence for the circuit.

37. The medium of claim 34, further comprising instructions for performing the step of outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a release complete message specifying a glare detection cause, based on the determining step and the glare control indicator specifying the switch has precedence for the circuit.

38. The medium of claim 34, further comprising instructions for performing the steps of:

detecting a release condition following initiating the outgoing call on of the circuit by the IP-based gateway; and

outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a message specifying the release condition indicating an availability of the circuit.

39. The medium of claim 34, further comprising instructions for performing the steps of:

detecting a changed status in at least one of the circuits; and

outputting a second IP-based message that specifies the trunk group identifier for the group of circuits including the at least one circuit, and status information that specifies at least the changed status for the one circuit.

40. An Internet Protocol (IP)-based node comprising:

means for establishing a prescribed trunk group having multiple sets of connected trunk groups coupled to respective IP-based gateway devices, the establishing means configured for storing trunk group entries within a table, each trunk group entry specifying an address for one of the IP-based gateway devices and an identified one of the connected trunk groups from the corresponding set of connected trunk groups;

means for selecting a circuit from a selected one of the connected trunk groups for connection with a switch having a peer trunk group interfacing with the prescribed trunk group; and

means for outputting an IP-based selection message, identifying the selected circuit for the connection with the switch, to the corresponding IP-based gateway device configured for controlling the selected one connected trunk group.

41. The IP-based node of claim 40, wherein the outputting means is configured for receiving an IP-based status message from one of the IP-based gateway devices that includes status information for circuits of an identified one of the corresponding connected trunk groups, the establishing means configured for storing, for each trunk group entry identifying the identified one connected trunk group, a circuit identifier for a corresponding circuit unique to the corresponding identified one connected trunk group, and a service status indicator specifying whether the corresponding circuit is in-service.

42. The IP-based node of claim 41, wherein the establishing means further is configured for parsing a circuit service status bit map, within the status information of the received IP-based status message and that specifies a status for each corresponding circuit of the identified one connected trunk group, for the service status indicator.

43. The IP-based node of claim 41, wherein each trunk group entry includes an allocated field value specifying whether the corresponding circuit has been allocated for a corresponding connection with the switch, the selecting means configured for selecting the circuit based on identifying a trunk group entry having a service status indicator indicating the corresponding circuit is in-service, and an allocated field value specifying that the corresponding circuit has not been allocated.

44. The IP-based node of claim 43, wherein:

the outputting means is configured for receiving a second IP-based message from the one IP-based gateway that specifies one of the corresponding connected trunk groups, the circuit identifier for a corresponding one of the circuits, and a status of the corresponding one circuit; and

the establishing means is configured for updating one of the service status indicator and the allocated field value for the trunk group entry corresponding to the one connected trunk group and circuit identifier specified in the second IP-based message.

45. The IP-based node of claim 40, wherein outputting means is configured for specifying, within the IP-based selection message, a glare control indicator specifying a prescribed glare protocol operation to be performed by the corresponding IP-based gateway in response to detection of glare by the IP-based gateway.

46. The IP-based node of claim 45, wherein the outputting means is configured for inserting, within the IP-based selection message, an IP address for the IP-based gateway device having the selected circuit, an identifier for the for the corresponding identified one trunk group having the selected circuit, and the corresponding circuit identifier for the selected circuit.

47. An Internet Protocol (IP)-based gateway having a set of connected trunk groups for connection to at least a portion of a peer trunk group of a switch, the IP-based gateway further comprising:

means for sending, to an IP-based node via an IP network, an IP-based message that specifies a trunk group identifier for a group of circuits, and status information for the group of circuits, and receiving, via the IP network, a call setup message that specifies one of the connected trunk groups, a circuit identifier, and a glare control indicator that specifies a prescribed glare arbitration;

means for determining whether the switch is attempting to seize the circuit specified by the circuit identifier for the one connected trunk group; and

means for selectively initiating an outgoing call on the circuit specified by the circuit identifier for the one connected trunk group, based on the determining step and the glare control indicator.

48. The IP-based gateway of claim 47, wherein the selectively initiating means is configured for determining whether the glare control indicator specifies whether the IP-based gateway has precedence for outgoing calls on the circuit, relative to incoming calls initiated by the switch.

49. The IP-based gateway of claim 48, wherein the selectively initiating means is configured for initiating the outgoing call on the circuit according to Q.764 protocol according to one of a determined availability of the circuit and a determined precedence for the circuit.

50. The IP-based gateway of claim 47, wherein the sending means is configured for outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a release complete message specifying a glare detection cause, based on the determined attempt by the switch to seize the circuit and the glare control indicator specifying the switch has precedence for the circuit.

51. The IP-based gateway of claim 47, wherein:

the determining means is configured for detecting a release condition following initiating the outgoing call on the circuit by the IP-based gateway; and

the sending means is configured for outputting a second IP-based message specifying the circuit identifier for the circuit, a trunk group identifier for the corresponding one connected trunk group, and a message specifying the release condition indicating an availability of the circuit.

52. The IP-based gateway of claim 47, wherein:

the determining means is configured for detecting a changed status in at least one of the circuits; and

the sending means is configured for outputting a second IP-based message that specifies the trunk group identifier for the group of circuits including the at least one circuit, and status information that specifies at least the changed status for the one circuit.