一种能有效支持QoS的光突发装配技术

A New Composite Optical Burst Assembly Techniqe Based on Adaptive-threshold to Support QoS

提出了一种新的光突发装配技术,目的在于增强光突发交换(OBS)网络的服务质量(QoS)能力。该技术由自适应门限突发装配算法和基于优先级的随机化的偏移时间设置方案构成。该装配算法特别适合于多类别分组混合装配,能让所有类别的分组公平有效地使用装配能力,能较好地与IP层的QoS机制相匹配。偏移设置方案将突发控制分组(BCP)与突发数据(BP)间的偏移时间分成QoS偏移和随机偏移,前者由改进的JET协议按照有选择性的突发段丢弃机制(BSSD)确定,后者则由令牌桶机制确定。BSSD仅丢弃包含有低类别分组的突发段,而非整个突发。计算机仿真结果表明,本文提出的突发装配技术在性能上具有优越性。

A new burst assembly technique for supporting quality of service(QoS) in optical burst switching(OBS) networks was proposed.It consists of the adaptivethreshold burst assembly algorithm and QoSbased random offsettime scheme.The algorithm is fit well to multiclass burst assembly,and not only matches with IP QoS mechanism based on packet classification,and also utilizes fairly and efficiently assembly capacity.The offsettime scheme can support OBS QoS,and smooth the traffic.It builds on the tokenbucket model and the modified Justenoughtime(JET) with burst segment selective discard(BSSD).BSSD only discards the burst segment containing lower class packets during conflict.The paper also provides the simulation for the performance improvement of technique in packet loss probability(PLP).