Computer Engineering and Applications ›› 2008, Vol. 44 ›› Issue (1): 21-24.

• 博士论坛 • Previous Articles     Next Articles

Real-time performance evaluation in switched ethernet by network calculus

HU Xiao-ya,ZHU De-sen,WANG Bing-wen   

  1. Department of Control Science and Engineering,Huazhong University of Science and Technology,The Key Laboratory of Image Processing and Intelligent Control,Wuhan 430074,China
  • Received:1900-01-01 Revised:1900-01-01 Online:2008-01-01 Published:2008-01-01
  • Contact: HU Xiao-ya

基于网络演算的交换式以太网实时特性分析

胡晓娅,朱德森,汪秉文   

  1. 华中科技大学 控制科学与工程系 图像信息处理与智能控制教育部重点实验室,武汉 430074
  • 通讯作者: 胡晓娅

Abstract: The focus that switched Ethernet is applied in the networked control system is ability of real-time.For this,a new analytic tool:network calculus is used to determinately analyze the special performances of the real-time data via a switched Ethernet.With scheduling algorithms FIFO(First Input First Output),the communication model is set up and network elements’ arrive curves and service curves are derived for a switched industrial Ethernet model with two levels’ tree topology.Then,analytic expressions of the worst case end-to-end delay,buffer size and output burstiness are presented,the maximum network delays of real-time data are calculated based on derived results.

Key words: network calculus, switched Ethernet, worst case delay bound

摘要: 交换式以太网在网络控制系统中的应用关键问题是实时能力,为此采用一种新型实时性能分析工具——网络演算,对交换式以太网实时能力进行确定性的分析和研究。针对FIFO调度算法,对两级树型拓扑结构的交换式以太网系统建立了通信模型,推导出各网络元素的到达曲线和服务曲线,由此得到了最大时延、所需缓冲区大小、输出突发量等实时业务流的主要参数解析表达式;利用推导所得结论计算了实时业务流的最大网络时延。

关键词: 网络演算, 交换式以太网, 时延上界