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SQM-LRU: A Harmony Dual-Queue Management Algorithm to Control Non-Responsive LTF Flow and Achieve Service
Penghui Li1, Xianliang Jiang1, Jiahua Zhu1
1Faculty of Electrical Engineering and Computer, Ningbo University, 818 Fenghua Road, Ningbo 315211, China.
This study introduces SQM-LRU, a novel active queue management scheme for Wide Area Networks (WANs). It effectively detects non-responsive Long-Term Fast (LTF) flows, improving service differentiation and reducing delays for responsive traffic.
Area of Science:
- Computer Science
- Network Engineering
- Data Communications
Background:
- Increasing network application diversity necessitates advanced service differentiation.
- Non-responsive Long-Term Fast (LTF) flows are primary causes of congestion in Wide Area Networks (WANs).
- Existing queue management algorithms struggle to differentiate traffic effectively, hindering differentiated services.
Purpose of the Study:
- To propose SQM-LRU, an active queue management scheme for service differentiation in WANs.
- To detect and suppress non-responsive LTF flows to enable controllable delay and service differentiation.
- To satisfy delay requirements for responsive flows while maximizing throughput for non-responsive LTF flows.
Main Methods:
- Developed SQM-LRU utilizing Shadow Queue (SQ) and an improved Least-Recently-Used (LRU) strategy for flow detection.
- Implemented a dual-queue system with CoDel and RED for packet management based on flow detection.
- Classified flows into high or low priority sub-queues according to detection results.
Main Results:
- SQM-LRU demonstrated superior performance in flow detection compared to traditional methods.
- Achieved significant reductions in delay, jitter, and Flow Completion Time (FCT) for responsive flows.
- Reduced FCT by up to 50% and maintained 95% link utilization.
Conclusions:
- SQM-LRU effectively enables service differentiation by distinguishing responsive and non-responsive flows.
- The scheme is practical for real-world networks due to its low overhead and O(1) cost per packet.
- SQM-LRU offers a viable solution for managing network congestion and improving Quality of Service (QoS).
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