摘要
To meet the requirements of modeling the new modality of peer-to-peer(P2P)network applications which have been rapidly developing in the Internet recently, a formal description method for modeling multiparty concurrent network interactions is studied. The main characteristics and the classifications of P2P systems are discussed. Considering the requirements of P2P application modeling and referring to the component-based modeling thought, a description method based on communicating sequential processes (CSP)is proposed for the P2P network models. By using a CSP process group, this method can describe the dynamic interactive relationship which focuses on multiparty concurrent interaction of P2P systems more advantageously and accurately. The application of nondeterministic semantemes of CSP in describing the interactive relationship of P2P networks is discussed. The advantages and description abilities of the proposed method are demonstrated through the modeling of a new P2P media-on-demand system.
为了更好地适应对Internet中迅速发展的新形态P2P网络应用进行建模的需求,深入研究了适于描述多方并发网络交互的形式化建模方法.首先,对P2P网络系统模型的各项特征及其分类进行了探讨.然后,参照构件化建模的研究思路,基于对P2P应用建模需求的分析,提出了一种运用通信顺序进程(CSP)进行描述的P2P网络应用的形式化描述方法.借助CSP进程组表示,该方法能够更为方便精确地描述P2P系统中以多方交互为主的动态交互关系,探讨了CSP非确定性语义在P2P交互建模中的应用.最后通过一个新型P2P媒体点播系统的实例展示了以上描述方法的应用,验证了该方法在描述并行交互关系等方面的能力.
基金
The National Basic Research Program of China (973 Program)(No.2003CB314801,2009CB320501)