计算机网络的建模与分析

计算机网络具有既随机又相关的特点，因此选择计算机网络性能评价的数学工具要考虑到网络数据流的特性，排队模型是一种确定性的数学模型，用确定性的模型描述网络既随机又相关的动态行为是不够的。Ｐｅ＃簦颍? Ｎｅｔｓ（ＰＮ）能够比较方便地刻画网络的相关录枋鐾绲木赫⑴鲎埠妥枞樱校谓肜┏浞⒄苟吹乃婊校危梢员冉戏奖愕目袒缡录乃婊裕呓岷掀鹄创酉嗟背潭壬匣汉土思扑慊缃Ｓ敕治鲋涞

MODELLING AND ANALYSIS OF COMPUTER NETWORKS

Computer networks have random and correlative characteristics. The choice of the mathematical tools for the performance evaluation of computer networks should consider the characteristics of data flow. This paper compares some mathematical tools for this challenge. Queueing model, which is often used to analyze the performance of computer systems, has its limit for describing the events which are characterized as both random and correlative, especially analyzing the end-to-end performance if the condition of product form solution is not satisfied. Petri Net is appropriate to characterize the correlative events of networks. Introducing the stochastic process into Petri Nets can describe the random characteristics of network events, and ease the contradiction between modeling and solution.Thus, Stochastic Petri Nets is an attractive modeling tools for the performance evaluation of computer networks.