Virtual circuit network dynamic channel management

• US 6,707,820 B1
• Filed: 12/16/1999
• Issued: 03/16/2004
• Est. Priority Date: 12/16/1999
• Status: Expired due to Term

• Current Assignee: Intervoice Limited Partnership
• Original Assignee: Intervoice Limited Partnership
• Inventors: Corey, Jerry Lee, Arndt, Richard Edwin
• Primary Examiner(s): Ton, Dang
• Assistant Examiner(s): HOM, SHICK C
• Application Number:
  US09/465,502
• Time in Patent Office: 1,552 Days
• Field of Search: 370/355, 370/360, 370/386, 370/395.2, 370/395.21, 370/395.3, 370/395.41, 370/395.42, 370/395.52, 370/400, 370/410, 379/229, 379/230, 709/220, 709/222, 709/223, 709/225, 709/227, 709/228, 709/229
• US Class Current: 370/395.2
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/746 Reaction triggered by a failure
• CPC Class Codes: H04L 47/801 Real time traffic
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/826 Involving periods of time
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42

Abstract

A method and system of managing virtual circuits for improved non-blocking fault tolerance in a multi-node virtual circuit network of resources is presented. On receiving a request for connection between two nodes in the multi-node network, a virtual circuit with a plurality of virtual circuit channels is set up between the two nodes. Each node may have more than one physical link equipped to it. Furthermore, the virtual circuit channel may be disconnected when there is no traffic between the nodes. A method for handling virtual circuit channel allocation and de-allocation that prevents conflicts in reuse of the channels before they are released by both nodes in the connection is also presented. A protocol to prevent race conditions between the nodes is also established providing improved bandwidth utilization in the multi-node network.

Claims

1. A method for allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a connection request on a receiving node, from an originating node, to establish a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said connection request to a preferred one of said first and second nodes;

allocating the channel by said preferred one of said first and second nodes for connecting said first and second resource connection points, wherein said allocating the channel comprises selecting a link equipped on said preferred one of said first and second nodes, wherein said allocated channel is a channel on said selected link;

connecting a preferred one of said first and second resource connection points with said allocated channel, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said connection request to the other one of said first and second nodes, wherein the second passed request includes said selected link and channel number; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

2. The method of claim 1, further comprising:

returning a completion response to said originating node.

3. The method of claim 1, wherein said determining step is performed by a connection control process on said receiving node.

4. The method of claim 1, wherein said passing said connection request to said preferred one of said first and second nodes comprises the step of:

passing said connection request to a first connection control process of said preferred one of said first and second nodes.

5. The method of claim 1, wherein said passing said connection request to the other one of said first and second nodes comprises the step of:

passing said connection request to a second connection control process of said other one of said first and second nodes.

6. The method of claim 1, wherein said virtual circuit network is a plurality of virtual circuits routed between said plurality of nodes connected to an Asynchronous Transfer Mode (ATM) network.

7. The method of claim 1, wherein at least one of said plurality of nodes is a processor based system selected from the group consisting of a computer and a server.

8. The method of claim 1, wherein said allocated channel is bandwidth allocated within a virtual circuit.

9. The method of claim 1, wherein said connection request is a Connection Control Process (CCP) Application Programming Interface (API) request made by an application program associated with said originating node.

10. The method of claim 9, wherein said application program provides a telecommunications based service.

11. The method of claim 9, wherein said application program is capable of originating, processing, and terminating outgoing telecommunication connections.

12. The method of claim 9, wherein said application program is capable of answering, processing, and terminating incoming telecommunication connections.

13. The method of claim 1, wherein said receiving node, said first node, and said second nodes are capable of processing Connection Control Process (CCP) Application Programming Interface (API) requests.

14. The method of claim 1, wherein said originating node and said receiving node are the same node.

15. The method of claim 1, wherein each of said first and second resource connection points (RCP) is a telecommunications resource controlled by a connection control process.

16. The method of claim 1, wherein said originating node and said preferred one of said first and second nodes are the same node.

17. The method of claim 1, wherein said originating node and said preferred one of said first and second nodes are different nodes.

18. The method of claim 1, wherein said preferred one of said first and second nodes is a node with a higher priority than the other node of said first and second nodes.

19. The method of claim 1, wherein said preferred one of said first and second nodes is a node with an identification number greater than the other one of said first and second nodes.

20. The method of claim 1, wherein said link is a link connected into an ATM network of said plurality of nodes.

21. The method of claim 1, wherein said link is selected from a plurality of links based on a load sharing criteria or based on a priority of said link.

22. The method of claim 1, wherein said selected link comprises a plurality of virtual circuits.

23. The method of claim 1, wherein said allocating channel step further comprises:

allocating said channel on said selected link.

24. The method of claim 1, wherein said connecting said other resource connection point to said allocated channel comprises:

verifying the availability of the selected link and channel; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

25. The method of claim 1, wherein said virtual circuit network is an Asynchronous Transfer Mode (ATM) network.

26. The method of claim 1, wherein said connection request is a TCP/IP message.

27. The method of claim 1, wherein said allocated channel is an ATM channel.

28. The method of claim 1, wherein said link is an ATM link.

29. A method for allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a connection request on a receiving node, from an originating node, to establish a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said connection request to a preferred one of said first and second nodes;

allocating the channel by said preferred one of said first and second nodes for connecting said first and second resource connection points, wherein said allocating the channel comprises selecting a link equipped on said preferred one of said first and second nodes, wherein said allocating the channel further comprises allocating said channel on said selected link, wherein said allocated channel is a channel selected from the group consisting of a first available channel on said link, a lowest numbered channel available on said link, a highest numbered channel available on said link, and a spare channel in a virtual circuit on said link;

connecting a preferred one of said first and second resource connection points with said allocated channel, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said connection request to the other one of said first and second nodes; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

30. The method of claim 29, wherein said virtual circuit is not set to a hold closed timeout state.

31. A method for allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a connection request on a receiving node, from an originating node, to establish a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said connection request to a preferred one of said first and second nodes;

allocating the channel by said preferred one of said first and second nodes for connecting said first and second resource connection points, wherein said allocating the channel comprises selecting a link equipped on said preferred one of said first and second nodes, wherein said allocating the channel further comprises allocating said channel on said selected link, wherein channels on said link are sequentially allocated;

connecting a preferred one of said first and second resource connection points with said allocated channel, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said connection request to the other one of said first and second nodes; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

32. A method for allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a connection request on a receiving node, from an originating node, to establish a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said connection request to a preferred one of said first and second nodes;

allocating the channel by said preferred one of said first and second nodes for connecting said first and second resource connection points, wherein said allocating the channel comprises selecting a link equipped on said preferred one of said first and second nodes, wherein said allocated channel is a channel on said selected link, wherein said selected link comprises a plurality of virtual circuits, wherein at least one of said plurality of virtual circuits has a plurality of virtual circuit channels associated with it, and wherein said allocated channel is one of said plurality of virtual circuit channels;

connecting a preferred one of said first and second resource connection points with said allocated channel, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said connection request to the other one of said first and second nodes; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

33. A method for allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a connection request on a receiving node, from an originating node, to establish a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said connection request to a preferred one of said first and second nodes;

allocating the channel by said preferred one of said first and second nodes for connecting said first and second resource connection points, wherein said allocating the channel comprises selecting a link equipped on said preferred one of said first and second nodes, wherein said allocating the channel further comprises allocating said channel on said selected link, wherein said allocating the channel further comprises translating said allocated channel to a virtual circuit number and a virtual circuit channel number;

connecting a preferred one of said first and second resource connection points with said allocated channel, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said connection request to the other one of said first and second nodes; and

connecting said other resource connection point to said allocated channel thereby completing said connection request.

34. A method for de-allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a disconnection request on a receiving node from an originating node to disconnect a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said received disconnection request to a preferred one of said first and second nodes;

disconnecting a preferred one of said first and second resource connection points from a virtual circuit channel associated with said one resource connection point, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes, wherein said disconnecting a preferred resource connection point further comprises de-allocating said channel associated with said one resource connection point;

passing said disconnection request to the other one of said first and second nodes;

disconnecting said other resource connection point from said channel thereby completing said disconnection request;

setting a virtual circuit associated with said de-allocated channel on said preferred node to a predetermined hold open timeout state if said virtual circuit channel is a last channel on said virtual circuit; and

waiting to receive a virtual circuit close message from said other node within a hold open timeout period.

35. The method of claim 34, further comprising:

sending a completion response to said originating node.

36. The method of claim 34, wherein said disconnecting said other resource connection point step further comprises the step of:

deallocating said channel associated with said other resource connection point.

37. The method of claim 34, wherein said determining step is performed by a connection control process on said receiving node.

38. The method of claim 34, wherein said passing said received disconnection request to said preferred node step comprises the step of:

passing said disconnection request to a first connection control process of said preferred one of said first and second nodes.

39. The method of claim 34, wherein said passing said received disconnection request to said other node step comprises the step of:

passing said disconnection request to a second connection control process of said other one of said first and second nodes.

40. The method of claim 34, wherein at least one of said plurality of nodes is a processor based system selected from the group consisting of a computer and a server.

41. The method of claim 34, wherein said disconnection request is a connection control process (CCP) Application Programming Interface (API) request made by an application program associated with said originating node.

42. The method of claim 41, wherein said application program provides a telecommunications based service.

43. The method of claim 34, wherein said receiving node, said first node, and said second node are nodes capable of processing CCP API requests.

44. The method of claim 34, wherein said originating node and said receiving node are the same node.

45. The method of claim 34, wherein each of said first and second resource connection point (RCP) is a telecommunications resource controlled by a connection control process.

46. The method of claim 34, wherein said originating node and said preferred one of said first and second nodes are the same node.

47. The method of claim 34, wherein said preferred one of said first and second nodes is a node with a lower priority than said other one node of said first and second nodes.

48. The method of claim 34, wherein said preferred one of said first and second nodes is a node with an identification number less than said other one of said first and second nodes.

49. The method of claim 34, wherein said second passed request includes information regarding said first passed request.

50. The method of claim 34, wherein said predetermined hold open timeout period is about three seconds.

51. The method of claim 34, further comprising:

canceling said preferred node virtual circuit hold opened timeout state upon receiving said virtual circuit closed message from said other node;

closing said preferred node virtual circuit;

releasing said closed virtual circuit for reuse; and

sending a the virtual circuit close message from said preferred node to said other node.

52. The method of claim 34, further comprising:

canceling said preferred node virtual circuit hold opened timeout state if said virtual circuit close message is not received by said preferred node within said hold open timeout period; and

reporting a system error.

53. The method of claim 34, wherein said originating node has an application program associated with it.

54. The method of claim 34, wherein said virtual circuit network is an Asynchronous Transfer Mode (ATM) network.

55. A method for de-allocating a channel on a virtual circuit network of a plurality of nodes, comprising:

receiving a disconnection request on a receiving node from an originating node to disconnect a connection between a first resource connection point and a second resource connection point;

determining a first node associated with said first resource connection point and a second node associated with said second resource connection point;

passing said received disconnection request to a preferred one of said first and second nodes;

disconnecting a preferred one of said first and second resource connection points from a virtual circuit channel associated with said one resource connection point, wherein said preferred resource connection point is associated with said preferred one of said first and second nodes;

passing said disconnection request to the other one of said first and second nodes;

disconnecting said other resource connection point from said channel thereby completing said disconnection request, wherein said disconnecting said other resource connection point comprises deallocating said channel associated with said other resource connection point;

closing a virtual circuit associated with said de-allocated channel on said other node if said de-allocated channel is a last channel on said virtual circuit;

setting said virtual circuit associated with said de-allocated channel on said other node to a predetermined hold closed timeout state;

sending a virtual circuit close message to said preferred node; and

waiting to receive a virtual circuit close message from said preferred node within a hold close timeout period.

56. The method of claim 55, wherein said predetermined hold close timeout period is about six seconds.

57. The method of claim 55, further comprising:

canceling said other node virtual circuit hold closed timeout state upon receiving said virtual circuit close message from said preferred node; and

releasing said closed virtual circuit for reuse.

58. The method of claim 55, further comprising:

canceling said other node virtual circuit hold closed timeout state if said virtual circuit close message is not received by said other node within said hold close timeout period;

releasing said other node virtual circuit for reuse; and

reporting a system error.