摘要
建立了一个考虑QoS和多流复用的通信量模型。模型中的通信量由大量有相同源和目的地址的,独立同分布的数据流汇聚而成,其中每个数据流又由许多独立的符合Pareto分布的ON/OFF支流构成。文章首先分析了支流构成的数据流的概率分布,然后分析得到了数据流复用后的流速的概率分布,接着结合分数Langevin运动方程,得到了一个流量计算公式,该公式属于扩展的分数布朗运动。通过引入分数Langevin运动方程可以将外部影响因子,内部影响因子和Hurst参数有机地联系起来,给通信量的单分形和多重分形一个清晰合理的物理解释。最后使用该模型分析了VoIP中多流复用后的QoS参数,得到了几个重要结论。
In this paper our goal is to design a traffic model that can be used in routers or by network administrators to assist in network design and management.The traffic in the model is the multiplexing of a large number of flows and Qos.The individual flow is composed of a lot of ON/OFF streams.In particular,here the ON/OFF streams being dealt with using probability distribution are different from the ON/OFF sources being superposed in some other papers.The model is flow-based and improved FBM(expanding Fractional Brownian Motion).The ON/OFF streams 's sojourn time accord with Pareto distribution.We take the traffic flows rate as a stochastic variable and deduce the probability distribution of it.Then we take it as a physical variable and think of it's acceleration.Utilizing the fractal Langevin motion equation we get a novel formula for computing the amount of traffic.It is improved FBM.The fractal Langevin motion equation gives a distinct and reasonable physical explanation for traffic trace.The explanation relates the Pareto parameters,external environment impact factors,with Hurst parameter.Finally,the parameter analysis of QoS after the the multiplexing of a large number of flows of VoIP are analyzed.Then we draw some important conclutions.
出处
《计算机工程与应用》
CSCD
北大核心
2004年第30期160-163,196,共5页
Computer Engineering and Applications
基金
国家863信息技术领域重大专项项目基金(编号:2002AA103051
2003AA103510)资助
关键词
自相似
分数Langevin运动方程
流量计算
QoS参数分析
self-similar model,fractal Langevin motion equation,computing the amount of traffic,parameter analysis of QoS
