弹性分组环的带宽利用率及公平策略分析

Bandwidth Utilization Factor and Fairness Policy Analysis of RPR

弹性分组环(ResilientPacketRing,RPR)是刚被IEEE802.17标准化的主要用于宽带IP光城域网的新型技术,其带宽利用效率和传统环网相比具有较大的优势。论文通过建立弹性分组环基本带宽模型并对其带宽利用率及带宽分配的公平策略进行分析。分析结果表明:RPR带宽利用率在“环形”业务模式下最高,而在星型业务模式下和传统环网相比则无优势;在比较接近实际情况的“网状”业务模式下,基于节点公平的带宽利用率可以到达传统环网的2倍,而基于流的公平策略的带宽利用率可以到达基于节点公平的近2倍,更适合于具有空间重利用能力的RPR。

Resilient Packet Ring（RPR） is a new technology has just been standardized as IEEE 802.17 for Metropolitan Area Networks （MAN）.RPR provides higher bandwidth utilization than other ring technologies.In this paper,we have developed primary bandwidth model of RPR and analysed its bandwidth utilization factor and fairness policy.The results show that RPR has maximum bandwidth utilization factor in ＂Ring＂ traffic pattern,and has no advantages than conventional rings in ＂star＂ traffic pattern,RPR can get two times of bandwidth utilization factor than conventional rings in ＂balance mesh＂ traffic pattern using node-based fairness policy,and a more nearly two times using flow-based fairness policy.