Chinese Journal of Computers   Full Text
Title	PFWRR: An Enhanced WRR Scheduling Realizing the Proportion Fairness Principle
Authors	WANG Sheng-Ling1)〓HOU Yi-Bin2)〓HUANG Jian-Hui1)〓HUANG Zhang-Qin2)
Address	1)(School of Electronics and Information Engineering, Xi’an Jiaotong University, Xi’an〓710049) 2)(College of Software Engineering, Beijing University of Technology, Beijing〓100022)
Year	2008
Issue	No.5(775—782)
Abstract &   Background	Abstract To realize proportion fairness principle, a scheduling based on Weighted Round Robin(WRR) is proposed, whose name is Proportion Fairness WRR(PFWRR). PFWRR adjusts each queue’s weight in terms of the average packet arrival rate to guarantee that the proportion of average queuing delay accords with the differentiation parameters when each queue’s length is smaller than or equals to its buffer length and the proportion of average packet loss rate accords with the differentiation parameters when the system begins to drop packets. The computation load of PFWRR is reasonable because it renews each queue’s weight only when the system is overloaded and the average packet arrival rate changes. The experiment shows that PFWRR can realize the average queuing delay proportion fairness principle when the system is overloaded but do not drop packets and the average packet loss rate proportion fairness principle when packet loss happens in the system. Keywords weighted round robin; proportion fairness; the average packet queuing delay; the average packet loss rate; the average packet arrival rate Background This work is supported by the Key Project Foundation of Technology and Development Program of Beijing Municipal Commission of Education (No.KZ2005100005006), and the National Natural Science Foundation of China (Nos.90407017, 60403035), and the National High Technology Development Program(863 Program) of China (No.2006AA01Z205). As an important solution providing QoS for users, packet scheduling has attracted many attentions. IETF has published many RFCs and drafts in this filed and a lot of top conferences and journals have proposed novel scheduling algorithms. However, most of existing packet scheduling algorithms do not guarantee fairness and priority at the same time. Thus some researchers improved them according to the proportion fairness principle, but regretfully their scheduling algorithms have high computational complexity. In this scenario, the authors propose a new packet scheduling algorithm realizing the proportion fairness principle, named PFWRR. PFWRR has low computation load because it renews each queue’s weight only when the system is overload and the average packet arrival rate changes. The authors’ projects focus on the key technologies in wireless/mobile network including QoS, security and modeling and so on. They have developed a prototype system of wireless access point with QoS, and have published some relevant papers.