Method and apparatus for communication network congestion control

• US 20070153695A1
• Filed: 12/29/2005
• Published: 07/05/2007
• Est. Priority Date: 12/29/2005
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Lee, Kuo-Chun, Gholmieh, Ralph
• Granted Patent: US 7,796,507 B2
• Time in Patent Office: Days
• US Class Current: 370/235
• CPC Class Codes: H04L 43/0882 Utilisation of link capacity
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/29 using a combination of thresholds
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/12 using signalling between network elements
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 88/12 Access point controller devices
• CPC Class Codes: H04W 92/12 between access points and access point controllers

Abstract

A communication network node, such as a radio base station or base station controller in a wireless communication network, is configured to monitor and control ingress and egress data congestion. As such, node-based congestion monitoring provides a method of flow control between network nodes and, as such, for example, it may be used to control congestion on backhaul links between radio base stations and base station controllers, and on sidehaul links between base station controllers. In one embodiment, the node monitors egress and ingress data congestion conditions, and marks ingress data incoming to the node to indicate congestion. For example, if ingress data markings indicate ingress data congestion, the node can send signaling to initiate a reduction in the amount of data being sent to the node, e.g., a reduction in ingress data rates. If ingress data markings indicate egress data congestion, the node can reduce egress data rates.

Claims

1. A method of congestion control at a communication network node comprising:

monitoring egress data congestion conditions at the node by comparing egress link utilization to one or more egress link utilization thresholds;

reducing egress data rates responsive to detecting egress data congestion;

monitoring ingress data congestion conditions at the node by comparing ingress link utilization to one or more ingress link utilization thresholds; and

reducing ingress data rates responsive to detecting ingress data congestion.

2. The method of claim 1, wherein monitoring egress and ingress data congestion conditions at the node further comprises selectively setting egress congestion indicators in ingress data incoming to the node based on said comparing egress link utilization to the one or more egress link utilization thresholds, and selectively setting ingress congestion indicators in ingress data incoming to the node based on said comparing ingress link utilization to the one or more ingress link utilization.

3. The method of claim 2, wherein reducing egress data rates responsive to detecting egress data congestion comprises, for one or more data processing applications running within the node, reducing egress data rates responsive to detecting the egress congestion indicators in the ingress data, and wherein reducing ingress data rates responsive to detecting ingress data congestion comprises, for the one or more data processing applications, sending signaling from the node to indicate that ingress data rates should be reduced.

4. A communication network node for use in a communication network, said node comprising one or more processing circuits configured to:

monitor for egress data congestion at the node;

set one or more egress congestion indicators if said egress monitoring indicates egress data congestion; and

reduce egress congestion responsive to the one or more egress congestion indicators.

5. The node of claim 4, wherein the node is configured to monitor for egress data congestion at the node by comparing egress link utilization to one or more utilization thresholds.

6. The node of claim 4, wherein the node is configured to set one or more egress congestion indicators if the egress link utilization is above a higher utilization threshold or if an egress data queue size is above an upper queue threshold, and clear the one or more egress congestion indicators if the egress link utilization is below a lower utilization threshold and the egress data queue size is below a lower queue threshold.

7. The node of claim 4, wherein the node is configured to reduce egress congestion by reducing the amount of egress data output from the node.

8. The node of claim 4, wherein the node is configured to set the one or more egress congestion indicators by setting egress congestion indicators in ingress data incoming to the node.

9. A communication network node for use in a communication network, said node comprising one or more processing circuits configured to:

monitor for ingress data congestion at the node;

set one or more ingress congestion indicators if said ingress monitoring indicates ingress data congestion; and

reduce ingress congestion responsive to the one or more ingress congestion indicators.

10. The node of claim 9, wherein the node is configured to monitor for ingress data congestion at the node by comparing ingress link utilization to one or more utilization thresholds.

11. The node of claim 9, wherein the node is configured to set one or more ingress congestion indicators if the ingress link utilization is above a higher utilization threshold, and clear the one or more ingress congestion indicators if the ingress link utilization is below a lower utilization threshold and the ingress data queue size is below a lower queue threshold.

12. The node of claim 9, wherein the node is configured to reduce ingress congestion by sending signaling from the node to reduce the amount of ingress data being sent to the node.

13. The node of claim 9, wherein the node is configured to set the one or more ingress congestion indicators by setting ingress congestion indicators in ingress data incoming to the node.

14. In a communication network, a method of congestion control at a communication network node, the method comprising:

monitoring for egress data congestion at the node;

setting one or more egress congestion indicators if said egress monitoring indicates egress data congestion; and

reducing egress congestion responsive to the one or more egress congestion indicators.

15. The method of claim 14, further comprising monitoring for ingress data congestion at the node, setting one or more ingress congestion indicators if said ingress monitoring indicates ingress data congestion, and reducing ingress congestion responsive to the one or more ingress congestion indicators.

16. The method of claim 15, wherein the node comprises a wireless communication network node handling a plurality of egress data streams and corresponding ingress data streams, and wherein said monitoring for egress and ingress data congestion comprises monitoring egress and ingress congestion conditions for one or more of the egress data streams and corresponding ingress data streams.

17. The method of claim 16, wherein setting the one or more egress and ingress congestion indicators comprises setting egress and ingress congestion indicators in selected ones of the ingress data streams, such that aggregate egress or ingress congestion conditions are relieved by operating on the selected egress data streams or corresponding ingress data streams.

18. The method of claim 17, wherein, if said egress monitoring indicates acceptable egress congestion conditions, probabilistically increasing egress data rates for one or more of the data streams, and, if said egress monitoring indicates unacceptable egress congestion conditions, deterministically reducing egress data rates for one or more of the data streams.

19. The method of claim 15, wherein monitoring egress data congestion at the node comprises monitoring egress link utilization relative to one or more egress link utilization thresholds, and wherein monitoring ingress data congestion at the node comprises monitoring ingress link utilization relative to one or more ingress link utilization thresholds.

20. The method of claim 19, wherein monitoring egress data congestion at the node additionally comprises monitoring egress data queue size relative to one or more queue thresholds.

21. The method of claim 20, wherein setting one or more egress congestion indicators if said monitoring indicates egress data congestion comprises setting one or more egress congestion indicators if the egress link utilization is above a higher utilization threshold or if the egress data queue size is above an upper queue threshold, and clearing the one or more egress congestion indicators if the egress link utilization is below a lower utilization threshold and the egress data queue size is below a lower queue threshold.

22. The method of claim 15, wherein reducing egress congestion comprises reducing the amount of egress data output from the node, and wherein reducing ingress congestion comprises sending signaling from the node to initiate a reduction in the amount of ingress data being sent to the node.

23. The method of claim 15, wherein setting one or more ingress congestion indicators setting ingress congestion indicators in the ingress data.

24. The method of claim 15, wherein reducing ingress congestion comprises sending signaling from the node to reduce the amount of ingress data being sent to the node.

25. The method of claim 15, wherein setting one or more egress congestion indicators comprises setting egress congestion indicators in a congestion monitoring table maintained at the node, and wherein setting one or more ingress congestion indicators comprises setting ingress congestion indicators in the congestion monitoring table.

26. The method of claim 14, wherein setting one or more egress congestion indicators comprises setting egress congestion indicators in ingress data received at the node.

27. The method of claim 14, wherein reducing egress congestion comprises reducing the amount of egress data output from the node.

28. In a communication network, a method of congestion control at a communication network node, the method comprising:

monitoring for ingress data congestion at the node;

setting one or more ingress congestion indicators if said ingress monitoring indicates ingress data congestion; and

reducing ingress congestion responsive to the one or more ingress congestion indicators.

29. The method of claim 28, further comprising monitoring for egress data congestion at the node, setting one or more egress congestion indicators if said egress monitoring indicates egress data congestion, and reducing egress congestion responsive to the one or more egress congestion indicators.

30. The method of claim 29, wherein the node comprises a wireless communication network node handling a plurality of egress data streams and corresponding ingress data streams, and wherein said monitoring for egress and ingress data congestion comprises monitoring egress and ingress congestion conditions for one or more of the egress data streams and corresponding ingress data streams.

31. The method of claim 30, wherein setting the one or more egress and ingress congestion indicators comprises setting egress and ingress congestion indicators in selected ones of the ingress data streams, such that aggregate egress or ingress congestion conditions are relieved by operating on the selected egress data streams or corresponding ingress data streams.

32. The method of claim 31, wherein, if said egress monitoring indicates acceptable egress congestion conditions, probabilistically increasing egress data rates for one or more of the data streams, and, if said egress monitoring indicates unacceptable egress congestion conditions, deterministically reducing egress data rates for one or more of the data streams.

33. The method of claim 29, wherein monitoring egress data congestion at the node comprises monitoring egress link utilization relative to one or more egress link utilization thresholds, and wherein monitoring ingress data congestion at the node comprises monitoring ingress link utilization relative to one or more ingress link utilization thresholds.

34. The method of claim 33, wherein monitoring egress data congestion at the node additionally comprises monitoring egress data queue size relative to one or more queue thresholds.

35. The method of claim 34, wherein setting one or more egress congestion indicators if said monitoring indicates egress data congestion comprises setting one or more egress congestion indicators if the egress link utilization is above a higher utilization threshold or if the egress data queue size is above an upper queue threshold, and clearing the one or more egress congestion indicators if the egress link utilization is below a lower utilization threshold and the egress data queue size is below a lower queue threshold.

36. The method of claim 29, wherein reducing egress congestion comprises reducing the amount of egress data output from the node, and wherein reducing ingress congestion comprises sending signaling from the node to initiate a reduction in the amount of ingress data being sent to the node.

37. The method of claim 29, wherein setting one or more egress congestion indicators comprises setting egress congestion indicators in a congestion monitoring table maintained at the node, and wherein setting one or more ingress congestion indicators comprises setting ingress congestion indicators in the congestion monitoring table.

38. The method of claim 29, wherein setting one or more egress congestion indicators comprises setting egress congestion indicators in ingress data received at the node.

39. The method of claim 29, wherein reducing egress congestion comprises reducing the amount of egress data output from the node.

40. The method of claim 28, wherein reducing ingress congestion comprises sending signaling from the node to reduce the amount of ingress data being sent to the node.

41. The method of claim 28, wherein setting one or more ingress congestion indicators comprises setting ingress congestion indicators in ingress data received at the node.

42. A communication network node for use in a communication network, said node comprising one or more processing circuits configured to:

monitor for egress and ingress data congestion at the node;

set one or more egress congestion indicators if said egress monitoring indicates egress data congestion, and set one or more ingress congestion indicators if said ingress monitoring indicates ingress data congestion; and

reduce egress congestion responsive to the one or more egress congestion indicators, and reduce ingress congestion responsive to the one or more ingress congestion indicators.

43. The node of claim 42, wherein the node is configured to set the one or more egress congestion indicators by setting egress congestion indicators in ingress data received at the node, and configured to set the one or more ingress congestion indicators by setting ingress congestion indicators in the ingress data.

44. The node of claim 42, wherein the node is configured to reduce egress congestion by reducing the amount of egress data output from the node, and to reduce ingress congestion by sending signaling from the node to initiate a reduction in the amount of ingress data being sent to the node.

45. The node of claim 42, wherein the node comprises a wireless communication network node handling a plurality of egress data streams and corresponding ingress data streams, and wherein the node is configured to monitor for egress and ingress data congestion by monitoring egress and ingress congestion conditions for one or more of the egress data streams and corresponding ingress data streams.

46. The node of claim 45, wherein the node is configured to set the one or more egress and ingress congestion indicators by setting egress and ingress congestion indicators in selected ones of the ingress data streams, such that aggregate egress or ingress congestion conditions are relieved by operating on the selected data streams.

47. The node of claim 45, wherein the node is configured to probabilistically increase egress data rates for one or more of the egress data streams if said egress monitoring indicates acceptable egress congestion conditions, and is configured to deterministically decrease egress data rates for one or more of the egress data streams if said egress monitoring indicates unacceptable egress congestion conditions.

48. The node of claim 42, wherein the node is configured to set the one or more egress congestion indicators by setting egress congestion indicators in a congestion monitoring table maintained at the node, and to set the one or more ingress congestion indicators by setting ingress congestion indicators in the congestion monitoring table.

49. The node of claim 42, wherein the node is configured to monitor egress data congestion at the node by monitoring egress link utilization relative to one or more egress link utilization thresholds, and is configured to monitor ingress data congestion at the node by monitoring ingress link utilization relative to one or more ingress link utilization thresholds.

50. The node of claim 49, wherein the node is configured to monitor egress data congestion at the node by additionally monitoring egress data queue size relative to one or more queue thresholds.

51. The node of claim 50, wherein the node is configured to set the one or more egress congestion indicators if said monitoring indicates egress data congestion by setting the one or more egress congestion indicators if the egress link utilization is above a higher utilization threshold or if the egress data queue size is above an upper queue threshold, and is configured to clear the one or more egress congestion indicators if the egress link utilization is below a lower utilization threshold and the egress data queue size is below a lower queue threshold.