Network service level agreement arrival-curve-based conformance checking

• US 7,680,922 B2
• Filed: 10/30/2003
• Issued: 03/16/2010
• Est. Priority Date: 10/30/2003
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Krstulich, Zlatko, Rabinovitch, Peter, Jansen, Arnold
• Primary Examiner(s): Srivastava, Vivek
• Assistant Examiner(s): Jakovac, Ryan J
• Application Number:
  US10/696,034
• Publication Number:
  US 20050097206A1
• Time in Patent Office: 2,329 Days
• Field of Search: 709/223, 709/224
• US Class Current: 709/224
• CPC Class Codes: H04L 41/142 using statistical or mathematical methods
• CPC Class Codes: H04L 41/5003 Managing SLA; Interaction between SLA and QoS
• CPC Class Codes: H04L 41/5009 Determining service level performance parameters or violations of service level contracts, e.g. violations of agreed response time or mean time between failures [MTBF]
• CPC Class Codes: H04L 41/509 wherein the managed service relates to media content delivery, e.g. audio, video or TV
• CPC Class Codes: H04L 43/062 related to network traffic

Abstract

A method and apparatus for assessing a communications'"'"' network adherence to Service Level Agreements (SLAs) is presented. The apparatus includes a arrival curve parameter derivation and arrival curve parameter reporting means. A arrival curve parameter generator may be implemented either in hardware for a predefined response in fitting arrival curves to cumulative content arrival variations, or in software for flexibility in the content traffic considered for assessment. The arrival curve generator may be associated with a physical port, a line card, or a network node. Arrival curve parameters defining arrival curves are employed by a Network Management System (NMS) in conjunction with communications network node and communications network service curves in performing SLA conformance assessments. The advantages are derived from a distributed content traffic characterization in terms of arrival curves, a reduced resource overhead in conveying arrival curve parameters without sacrificing SLA assessment thoroughness.

Claims

1. A method of characterizing a content traffic flow at communication nodes of a communications network for communications network Service Level Agreement (SLA) compliance assessment by a network management system (NMS) connected to said communication nodes, the method comprising:

at least one of said communication nodes tracking cumulative content arrivals, in real time, for the content traffic flow to derive a time variation of cumulative content arrivals;

said at least one of said nodes adjusting characteristic arrival curve parameters, the arrival curve parameters comprising at least b, a degree of burst transmission, r, a sustainable content conveyance rate, M, a maximum packet size, and p, a peak content conveyance rate, in fitting an arrival curve to the variation of cumulative content arrivals for the content traffic flow; and

said at least one of said nodes reporting said adjusted arrival curve parameters to said NMS to enable said NMS to carry out said SLA compliance assessment with respect to the content traffic flow, thereby reducing reporting bandwidth overhead by minimizing an amount of content arrival information communicated to said NMS.

2. The method of providing a content traffic flow characterization as claimed in claim 1, wherein reporting arrival curve parameters to the NMS is carried out in real time, and reporting is limited to arrival curve parameters only.

3. The method claimed in claim 1, further comprising:

said at least one of said nodes including a timestamp specifying the time of the arrival curve fit.

4. The method claimed in claim 1, further comprising:

said at least one of said nodes receiving a request for an arrival curve parameter update;

reporting arrival curve parameters to the NMS only in response to a request; and

further providing a reduction in the reporting bandwidth overhead.

5. The method claimed in claim 1, further comprising:

said at least one of said nodes tracking one of cumulative received packets, bits, bytes, words, and double words.

6. The method claimed in claim 1, further comprising:

said at least one of said nodes fitting the arrival curve in accordance with one of a shifted linear regression procedure, and a convex hull fitting procedure.

35. The method as claimed in claim 1, wherein said tracking, adjusting, and reporting are carried out by more than one of said communication nodes.

7. A method of assessing communications network conformance to a Service Level Agreement (SLA) in respect of a content traffic flow at communication nodes of a communications network, the method comprising:

receiving from at least one of said communication nodes an arrival curve parameter report in respect of a tracked content traffic flow in real time;

computing a resource utilization related value based on the received arrival curve parameter report in respect of a content traffic flow pattern and at least one service curve; and

providing a communications network SLA conformance assessment to a network management system (NMS) based on the computed resource utilization related value, wherein receiving arrival curve parameters, the arrival curve parameters comprising at least b, a degree of burst transmission, r, a sustainable content conveyance rate, M, a maximum packet size, and p, a peak content conveyance rate, only enables the provision of a real-time scalable communications network SLA conformance assessment solution while reducing reporting bandwidth overhead by minimizing an amount of content arrival information communicated by said at least one of said nodes.

8. The method claimed in claim 7, further comprising:

the NMS requesting an arrival curve parameter report from said one of said nodes.

9. The method claimed in claim 7, further comprising:

retrieving the at least one service curve from storage in respect of the content traffic flow.

10. The method claimed in claim 7, further comprising:

retrieving the at least one service curve from said at least one node, said at least one node being in a path of the content traffic flow.

11. The method claimed in claim 7, further comprising:

retrieving from storage a sequence in which multiple service curves are to be combined with the arrival curve parameters in respect of the content traffic flow.

12. The method claimed in claim 7, further comprising:

discovering a sequence in which multiple service curves are to be combined with the arrival curve parameters in respect of the content traffic flow.

13. The method claimed in claim 7, further comprising:

computing Quality-of-Service (QoS) parameters.

14. The method claimed in claim 7, further comprising:

convolving an arrival curve respecting the received arrival curve parameters with a service curve.

15. The method claimed in claim 7, further comprising:

comparing the computed resource utilization related value with a corresponding agreed upon resource utilization value.

16. The method claimed in claim 7, further comprising:

selectively modifying communications network operational parameters to ensure that the resource utilization values comply with agreed upon SLA resource utilization values.

17. The method claimed in claim 7, further comprising:

selectively modifying SLA specified resource utilization values to ensure that the current communications network operation is accommodated in the SLA.

18. The method claimed in claim 7, further comprising:

providing a proposal for traffic content redirection onto one of existing infrastructure and new to be deployed infrastructure.

36. The method as claimed in claim 7, wherein said arrival curve parameter report is received from more than one of said communication nodes.

19. A method of centrally assessing communications network conformance to a Service Level Agreement (SLA) in respect of a content traffic flow at least one of a plurality of communication nodes of a communications network, the method comprising:

said at least one communication node tracking cumulative content arrivals for the content traffic flow, in real-time, to derive a time variation of cumulative content arrivals at a communications network node;

said at least one of said nodes adjusting arrival curve parameters, the arrival curve parameters comprising at least b, a degree of burst transmission, r, a sustainable content conveyance rate, M, a maximum packet size, and p, a peak content conveyance rate, in fitting an arrival curve to the variation of cumulative content arrivals for the content traffic flow;

said at least one node reporting, in real time, the arrival curve parameters to a network management system (NMS) assessing communications network SLA conformance with respect to the content traffic flow;

said NMS receiving an arrival curve parameter report in respect of a tracked content traffic flow from said at least one network node in real-time;

computing a resource utilization related value based on the received arrival curve parameter report in respect of a content traffic flow pattern and at least one service curve;

providing a communications network SLA conformance assessment based on the computed resource utilization related value; and

employing arrival curve parameter reporting reducing resource overheads in providing communications network SLA conformance assessments.

20. The method claimed in claim 19, further comprising:

said at least one of said nodes including a timestamp specifying the time of the arrival curve fit.

21. The method claimed in claim 20, further comprising:

said at least one of said nodes receiving a request for an arrival curve parameter update;

reporting arrival curve parameters to the NMS only in response to a request; and

further providing a reduction in the reporting bandwidth overhead.

22. The method claimed in claim 19, further comprising:

said at least one of said nodes tracking one of cumulative received packets, bits, bytes, words, and double words.

23. The method claimed in claim 19, further comprising:

said at least one of said nodes fitting the arrival curve in accordance with one of a shifted linear regression procedure, and a convex hull fitting procedure.

24. The method claimed in claim 19, further comprising:

requesting an arrival curve parameter report from said at least one of said nodes.

25. The method claimed in claim 19, further comprising:

retrieving the at least one service curve from storage in respect of the content traffic flow.

26. The method claimed in claim 19, further comprising:

retrieving the at least one service curve from said at least one node, said at least one node being in a path of the content traffic flow.

27. The method claimed in claim 19, further comprising:

retrieving from storage a sequence in which multiple service curves are to be combined with the arrival curve parameters in respect of the content traffic flow.

28. The method claimed in claim 19, further comprising:

discovering a sequence in which multiple service curves are to be combined with the arrival curve parameters in respect of the content traffic flow.

29. The method claimed in claim 19, further comprising:

computing Quality-of Service (QoS) parameters.

30. The method claimed in claim 19, further comprising:

convolving an arrival curve respecting the received arrival curve parameters with a service curve.

31. The method claimed in claim 19, further comprising:

comparing the computed resource utilization related value with a corresponding agreed upon resource utilization value.

32. The method claimed in claim 19, further comprising:

selectively modifying communications network operational parameters to ensure that the resource utilization values comply with agreed upon SLA resource utilization values.

33. The method claimed in claim 19, further comprising:

selectively modifying SLA specified resource utilization values to ensure that the current communications network operation is accommodated in the SLA.

34. The method claimed in claim 19, further comprising:

providing a proposal for traffic content redirection onto one of existing infrastructure and new to be deployed infrastructure.

37. The method as claimed in claim 19, wherein said tracking, adjusting, and reporting are carried out by more than one of said communication nodes, and said arrival curve parameter report is received from more than one of said communication nodes.