端到端(p,k)约束流的实时通讯  

End-to-end Real-Time Communication for Streams with (p,k) Constraint

作　　者：吴彤[1] 金士尧[1] 

机构地区：[1]国防科技大学计算机学院,湖南长沙410073

出　　处：《计算机仿真》2008年第12期146-150,共5页Computer Simulation

摘　　要：端到端系统的实时服务保证问题是当前广泛研究的问题。由于许多端到端应用可以容忍部分报文丢失,因此将窗口约束引入到端到端系统实时服务保证中,但是现有的端到端实时调度算法仅从固定窗口约束出发来保证实时服务,导致其在重度过载情况下性能下降显著。从基于可变窗口的(p,k)约束的角度出发保证实时数据流通过一系列服务器达到目的地的实时服务质量,提出了多跳K窗口约束调度(Multi-hop K-Window Constraint Scheduling,M-KWCS)算法,使其在重度过载下服务质量退化缓慢。实验表明M-KWCS算法在重度过载情况下的性能优于其它各类算法。Nowadays, the problem of meeting real - time end - to - end service guarantees is widely researched. Since many applications can tolerate some packets being discarded, window constraints are introduced into the end - to -end system to guarantee the real -time service. Unfortunately, current end -to- end real -time scheduling algorithms are based on the fixed window constraints which would result in poor performance under heavy load conditions. Based on the （p,k） constraint which is based on variable window, this paper presents a novel real - time scheduling algorithm called Multi - hop K - Window Constraint Scheduling （ M - KWCS）, and M - KWCS is used to guarantee the quality of service of the real - time data stream across a sequence of servers. Under heavy overload conditions, the QoS of real - time stream degrads slowly by M - KWCS＇s scheduling. Experiments show that M - KWCS can provide better performance than other algorithms under hard overload conditions.

关 键 词：服务质量 窗口约束 窗口约束调度 端到端系统 

分 类 号：TP316[自动化与计算机技术—计算机软件与理论]