Congestion avoidance approach for a switching communication system with transmission constraints

• US 6,738,350 B1
• Filed: 07/25/2000
• Issued: 05/18/2004
• Est. Priority Date: 03/16/2000
• Status: Expired due to Term

• Current Assignee: Hughes Network Systems LLC (Echostar Corporation)
• Original Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Inventors: Su, Chi-Jiun, Gao, Zhengping, Demers, Stephanie
• Primary Examiner(s): Ton, Dang
• Assistant Examiner(s): Scheibel, Robert C
• Application Number:
  US09/625,289
• Time in Patent Office: 1,393 Days
• Field of Search: 370/230, 370/232, 370/235, 370/328-330, 370/337, 370/338, 370/345, 370/347, 370/310.1, 370/310.2, 370/316, 370/321, 370/326, 370/501, 455/429, 455/453, 455/452.2, 455/422.1, 455/427, 455/428
• US Class Current: 370/232
• CPC Class Codes: H04B 7/18584 Arrangements for data networking, i.e. for data packet routing, for congestion control data switching networks H04L12/00
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/0289 Congestion control load shedding arrangements in network planning H04W16/08; performing reselection for handling the traffic H04W36/22; wireless traffic scheduling H04W72/12
• CPC Class Codes: H04W 28/20 Negotiating bandwidth
• CPC Class Codes: H04W 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185

Abstract

An approach for performing congestion avoidance in a switching communication system is disclosed. An input port of the switching communication system receives a bandwidth request from a source. The switching communication system includes a bandwidth control processor that examines the bandwidth request, and multiple output ports. The output ports communicate with various destination sites. A congestion avoidance logic within the switching communication system generates multiple clusters based upon a transmission constraint associated with the output ports; each of the clusters corresponds to a portion of the destination sites. The congestion avoidance logic determines a cluster threshold that corresponds to traffic load distribution among the critical clusters. Additionally, the congestion avoidance logic selectively grants the bandwidth request based upon the determined cluster threshold. This congestion avoidance mechanism has applicability to a packet-switched satellite communication system with an on-board switch; the switch has transmission constraints such that the transmitters of the satellite at the output port of the switch cannot simultaneously transmit to downlink cells, which contain station terminals that are within an interfering distance from one another.

Claims

1. A method of performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the method comprising:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells;

generating a critical cluster list based upon traffic statistics of the downlink cells;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint;

selectively granting the bandwidth request based upon the step of determining the cluster threshold and the critical cluster list.

6. The method according to claim 1, wherein the cluster threshold in the step of determining is based upon a Time Division Multiple Access (TDMA) slot.

7. The method according to claim 1, further comprising:

determining another cluster threshold,

wherein the selectively granting step is based upon the plurality of cluster thresholds.

14. The method according to claim 1, wherein, in the step of generating, the destination sites are nodes and the transmission constraint specifies a routing limitation associated with simultaneous transmission to a portion the nodes.

15. The method according to claim 14, wherein each of the clusters in the determining step specifies a maximal set of the nodes that conform with the transmission constraint.

2. A method of performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the method comprising:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage area,

computing a plurality of angles between the target downlink cell and remaining ones of the downlink cells in the coverage area,

comparing the computed angles corresponding to the downlink cells with a predetermined angle,

designating downlink cells to be in the interference region if the downlink cells have corresponding angles that are less than or equal to the predetermined angles, and

determining the clusters within the interference region of a targeted one of the downlink cells;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

3. The method according to claim 2, wherein the step of determining the interference region further comprises:

selectively designating dummy downlink cells around the target downlink cell based upon position of the target downlink cell within the coverage area.

4. A method of performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the method comprising:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells including,

determining which of the downlink cells within the interference region are located on a periphery of the interference region,

selecting a predetermined number of peripheral downlink cells to designate as being a part of the cluster,

computing angles between each of the downlink cells within the interference region and each of the peripheral downlink cells, and

designating a portion of the downlink cells within the interference region to be a part of the cluster if the angle between each of the downlink cells within the interference region and each of the peripheral downlink cells is less than or equal to the predetermined angle;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

5. A method of performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the method comprising:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells;

eliminating clusters that are redundant and duplicative;

generating a cluster list based upon the eliminating step;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the cluster list and the step of determining the cluster threshold.

8. The method according to claim 5, wherein the bandwidth request in the receiving step is at least one of a connection-oriented (CO) request and a connectionless (CL) request.

9. The method according to claim 8, further comprising:

determining a destination address associated with the bandwidth request;

determining whether the bandwidth request is the CO request or the CL request, wherein the CO request has a higher priority than the CL request, the CO request being at least one of a CO session release request and a CO session setup release request; and

determining an amount of desired bandwidth.

10. The method according to claim 9, further comprising:

accumulating a plurality of bandwidth requests;

processing the CO session release requests;

processing the CO session setup requests; and

processing the CL requests.

11. The method according to claim 10, wherein the step of processing the CO session release requests comprises:

releasing bandwidth allocations from the clusters within the cluster list having a downlink cell associated with the destination address.

12. The method according to claim 10, wherein the step of processing the CO session setup requests comprises:

determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters; and

computing available bandwidths for the CO session setup requests based upon the step of determining available bandwidths of the clusters, wherein each of the available bandwidths for the CO session setup requests is set to a minimum value of the available bandwidths of the clusters,

wherein the step of selectively granting comprises allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

13. The method according to claim 10, wherein the step of processing the CL requests comprises:

determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters; and

computing available bandwidths for the CL service requests based upon the step of determining available bandwidths of the clusters, wherein each of the available bandwidths for the CL service requests is set to a minimum value of the available bandwidths of the clusters,

wherein the step of selectively granting comprises allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

16. The method according to claim 10, wherein the step of selectively granting comprises allocating a granted bandwidth equal to the desired bandwidth if the destination address of the request does not correspond to a downlink cell within the cluster list.

17. A switching system comprising:

a plurality of input ports, one of the input ports receiving a bandwidth request;

a bandwidth control processor coupled to the plurality of input ports and configured to examine the bandwidth request;

a plurality of output ports communicating with a plurality of destination sites; and

a congestion avoidance logic configured to perform the steps of;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of the plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including determining an interference region for each of the downlink cells in a coverage area and the clusters within the interference region of a targeted one of the downlink cells,

generating a critical cluster list based upon traffic statistics of the downlink cells,

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint,

selectively granting the bandwidth request based upon the step of determining the cluster threshold and the critical cluster list.

22. The system according to claim 17, wherein the cluster threshold is based upon a Time Division Multiple Access (TDMA) slot.

23. The system according to claim 17, wherein the congestion avoidance logic is configured to determine another cluster threshold.

30. The system according to claim 17, wherein the destination sites are nodes and the transmission constraint specifies a routing limitation associated with simultaneous transmission to a portion the nodes.

31. The system according to claim 30, wherein each of the clusters specifies a maximal set of the nodes that conform with the transmission constraint.

18. A switching system comprising:

a plurality of input ports, one of the input ports receiving a bandwidth request;

a bandwidth control processor coupled to the plurality of input ports and configured to examine the bandwidth request;

a plurality of output ports communicating with a plurality of destination sites; and

a congestion avoidance logic configured to perform the steps of;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of the plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage area and the clusters within the interference region of a targeted one of the downlink cells,

computing a plurality of angles between the target downlink cell and remaining ones of the downlink cells in the coverage area,

comparing the computed angles corresponding to the downlink cells with a predetermined angle, and

designating downlink cells to be in the interference region if the downlink cells have corresponding angles that are less than or equal to the predetermined angles;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint, and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

19. The system according to claim 18, wherein the congestion avoidance logic selectively designates dummy downlink cells around the target downlink cell based upon position of the target downlink cell within the coverage area.

20. A switching system comprising:

a plurality of input ports, one of the input ports receiving a bandwidth request;

a bandwidth control processor coupled to the plurality of input ports and configured to examine the bandwidth request;

a plurality of output ports communicating with a plurality of destination sites; and

a congestion avoidance logic configured to perform the steps of;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of the plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage areas, and

determining the clusters within the interference region of a targeted one of the downlink cells including,

determining which of the downlink cells within the interference region are located on a periphery of the interference region,

selecting a predetermined number of peripheral downlink cells to designate as being a part of the cluster,

computing angles between each of the downlink cells within the interference region and each of the peripheral downlink cells and angles between each of the downlink cells within the interference region and each cell within the cluster, if any, and

designating a portion of the downlink cells within the interference region to be a part of the cluster if the angle between each of the downlink cells within the interference region and each of the peripheral downlink cells is less than or equal to the predetermined angle,

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint, and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

21. A switching system comprising:

a plurality of input ports, one of the input ports receiving a bandwidth request;

a bandwidth control processor coupled to the plurality of input ports and configured to examine the bandwidth request;

a plurality of output ports communicating with a plurality of destination sites; and

a congestion avoidance logic configured to perform the steps of;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of the plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including determining an interference region for each of the downlink cells in a coverage area and the clusters within the interference region of a targeted one of the downlink cells,

generating a cluster list by eliminating clusters that are redundant and duplicative,

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint, and

selectively granting the bandwidth request based upon the cluster list and the step of determining the cluster threshold.

24. The system according to claim 21, wherein the bandwidth request in the receiving step is at least one of a connection-oriented (CO) request and a connectionless (CL) request.

25. The system according to claim 24, wherein the bandwidth request includes a destination address and an amount of desired bandwidth, the bandwidth control processor configured to determine whether the bandwidth request is the CO request or the CL request, wherein the CO request has a higher priority than the CL request, the CO request being at least one of a CO session release request and a CO session setup release request.

26. The system according to claim 25, wherein the bandwidth control processor is configured to accumulate a plurality of bandwidth requests that include at least one of CO session release requests, CO session setup requests, and CL requests, the bandwidth control processor processing the bandwidth requests according to a prescribed order based upon a type of bandwidth request.

27. The system according to claim 26, wherein the congestion avoidance logic is configured to process the CO session release requests by releasing bandwidth allocations from the clusters within the cluster list having a downlink cell associated with the destination address.

28. The system according to claim 26, wherein the congestion avoidance logic is configured to process the CO session setup requests by determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters, computing available bandwidths for the CO session setup requests based upon the determined available bandwidths of the clusters, wherein each of the available bandwidths for the CO session setup requests is set to a minimum value of the available bandwidths of the clusters, the congestion avoidance logic allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

29. The system according to claim 26, wherein the congestion avoidance logic is configured to process the CL requests by determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters, and computing available bandwidths for the CL service requests based upon the step of determining available bandwidths of the clusters, wherein each of the available bandwidths for the CL service requests is set to a minimum value of the available bandwidths of the clusters, the congestion avoidance logic allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

32. The system according to claim 26, wherein the congestion avoidance logic is configured to allocate a granted bandwidth equal to the desired bandwidth if the destination address of the request does not correspond to a downlink cell within the cluster list.

33. A computer-readable medium carrying one or more sequences of one or more instructions for performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the one or more sequences of one or more instructions including instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance, the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells;

generating a critical cluster list based upon traffic statistics of the downlink cells;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint;

selectively granting the bandwidth request based upon the step of determining the cluster threshold and the critical cluster list.

38. The computer readable medium according to claim 33, wherein the cluster threshold in the step of determining is based upon a Time Division Multiple (TDMA) slot.

39. The computer readable medium according to claim 33, further comprising computer-executable instructions for causing the computer system to perform the steps of:

determining another cluster threshold,

wherein the selectively granting step is based upon the plurality of cluster thresholds.

46. The computer readable medium according to claim 33, wherein, in the step of generating, the destination sites are nodes and the transmission constraint specifies a routing limitation associated with simultaneous transmission to a portion of the nodes.

47. The computer readable medium according to claim 46, wherein each of the clusters in the determining step specifies a maximal set of the nodes that conform with the transmission constraint.

34. A computer-readable medium carrying one or more sequences of one or more instructions for performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the one or more sequences of one or more instructions including instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance the generating step including,

determining an interference region for each of the downlink cells in a coverage area,

computing a plurality of angles between the target downlink cell and remaining ones of the downlink cells in the coverage area,

comparing the computed angles corresponding to the downlink cells with a predetermined angle, and designating downlink cells to be in the interference region if the downlink cells have corresponding angles that are less than or equal to the predetermined angles, and

determining the clusters within the interference region of a targeted one of the downlink cells;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

35. The computer readable medium according to claim 34, wherein the step of determining the interference region further comprises:

selectively designating dummy downlink cells around the target downlink call based upon position of the target downlink cell within the coverage area.

36. A computer-readable medium carrying one or more sequences of one or more instructions for performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the one or more sequences of one or more instructions including instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells including,

determining which of the downlink cells within the interference region are located on a periphery of the interference region,

selecting a predetermined number of peripheral downlink cells to designate as being a part of the cluster,

computing angles between each of the downlink cells within the interference region and each of the peripheral downlink cells, and

designating a portion of the downlink cells within the interference region to be a part of the cluster if the angle between each of the downlink cells within the interference region and each of the peripheral downlink cells is less than or equal to the predetermined angle;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the step of determining the cluster threshold.

37. A computer-readable medium carrying one or more sequences of one or more instructions for performing congestion avoidance in a switching system having a plurality of input ports and a plurality of output ports, the one or more sequences of one or more instructions including instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

receiving a bandwidth request at one of the input ports;

generating a plurality of clusters based upon a transmission constraint associated with the output ports, each of the clusters designating a portion of a plurality of destination sites, wherein the destination sites are downlink cells and the transmission constraint specifies restriction of transmission to a portion of the downlink cells that are within a system limit interference distance the generating step including,

determining an interference region for each of the downlink cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the downlink cells;

eliminating clusters that are redundant and duplicative;

generating a cluster list based upon the eliminating step;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters, each of the clusters specifying a maximal set of the downlink cells that conform with the transmission constraint; and

selectively granting the bandwidth request based upon the cluster list and the step of determining the cluster threshold.

40. The computer readable medium according to claim 37, wherein the bandwidth request in the receiving step is at least one of a connection-oriented (CO) request and a connectionless (CL) request.

41. The computer readable medium according to claim 40, further comprising computer-executable instructions for causing the computer system to perform the steps of:

determining a destination address associated with the bandwidth request;

determining whether the bandwidth request is the CO request or the CL request, wherein the GO request has a higher priority than the CL request, the CO request being at least one of a CO session release request and a CO session setup release request; and

determining an amount of desired bandwidth.

42. The computer readable medium according to claim 41, further comprising computer-executable instructions for causing the computer system, to perform the steps of:

accumulating a plurality of bandwidth requests;

processing the CO session release requests;

processing the CO session setup requests; and

processing the CL requests.

43. The computer readable medium according to claim 42, wherein the step of processing the CO session release requests comprises:

releasing bandwidth allocations from the clusters within the cluster list having a downlink cell associated with the destination address.

44. The computer readable medium according to claim 42, wherein the step of processing the CO session setup requests comprises:

determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters; and

computing available bandwidths for the CO session setup requests based upon the step of determining available bandwidths of the clusters, wherein each of the available bandwidths for the CO session setup requests is set to a minimum value of the available bandwidths of the clusters,

wherein the step of selectively granting comprises allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

45. The computer readable medium according to claim 42, wherein the step of processing the CL requests comprises:

determining available bandwidths of the clusters that have a downlink cell associated with the destination address based upon a difference between the cluster threshold and current traffic loads of the corresponding clusters; and

computing available bandwidths for the CL service requests based upon the step of determining available bandwidths of the clusters, wherein each of the available bandwidths for the CL service requests is set to a minimum value of the available bandwidths of the clusters,

wherein the step of selectively granting comprises allocating a granted bandwidth based upon a minimum of the requested bandwidth and the available bandwidth.

48. The computer readable medium according to claim 42, wherein the step of selectively granting comprises allocating a granted bandwidth equal to the desired bandwidth if the destination address of the request does not correspond to a downlink cell within the cluster list.

49. A method of providing congestion avoidance associated with a plurality of cells, the method comprising:

generating a plurality of clusters based upon a transmission constraint that specifies restriction of transmission to a portion of the cells that are within a system limit interference distance, each of the clusters designating a portion of a plurality of destination sites;

determining an interference region for each of the cells in a coverage area;

determining the clusters within the interference region of a targeted one of the cells;

generating a critical cluster list based upon traffic statistics including the traffic load distribution of the cells;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters; and

selectively granting a bandwidth request based upon the critical cluster list and satisfaction of the cluster threshold.

50. A method of providing congestion avoidance associated with a plurality of cells, the method comprising:

generating a plurality of clusters based upon a transmission constraint that specifies restriction of transmission to a portion of the cells that are within a system limit interference distance, each of the clusters designating a portion of a plurality of destination sites including,

determining an interference region for each of the cells in a coverage area;

determining the clusters within the interference region of a targeted one of the cells;

computing a plurality of angles between the target cell and remaining ones of the cells in the coverage area;

comparing the computed angles corresponding to the cells with a predetermined angle;

designating cells to be in the interference region if the cells have corresponding angles that are less than or equal to the predetermined angles;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters; and

selectively granting a bandwidth request based upon satisfaction of the cluster threshold.

51. A method of providing congestion avoidance associated with a plurality of cells, the method comprising:

generating a plurality of clusters based upon a transmission constraint that specifies restriction of transmission to a portion of the cells that are within a system limit interference distance, each of the clusters designating a portion of a plurality of destination sites including,

determining an interference region for each of the cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the cells including,

determining which of the cells within the interference region are located on a periphery of the interference region,

selecting a predetermined number of peripheral cells to designate as being a part of the cluster,

computing angles between each of the cells within the interference region and each of the peripheral cells,

designating a portion of the cells within the interference region to be a part of the cluster if the angle between each of the cells within the interference region and each of the peripheral cells is less than or equal to the predetermined angle;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters; and

selectively granting a bandwidth request based upon satisfaction of the cluster threshold.

52. A method of providing congestion avoidance associated with a plurality of cells, the method comprising:

generating a plurality of clusters based upon a transmission constraint that specifies restriction of transmission to a portion of the cells that are within a system limit interference distance, each of the clusters designating a portion of a plurality of destination sites including,

determining an interference region for each of the cells in a coverage area, and

determining the clusters within the interference region of a targeted one of the cells;

eliminating clusters that are redundant and duplicative;

generating a cluster list based upon the eliminating step;

determining a cluster threshold corresponding to traffic load distribution among a portion of the plurality of clusters; and

selectively granting a bandwidth request based upon the cluster list and satisfaction of the cluster threshold.