Analyzing Service Rates for File Transfers in Peer-to-peer File Sharing Systems  

作　　者：王凯 潘理 李建华 

机构地区：[1]School of Electronic,Information and Electrical Engineering,Shanghai Jiaotong University

出　　处：《Journal of Donghua University(English Edition)》2008年第6期700-705,共6页东华大学学报（英文版）

基　　金：National High Technology Research and Development Program of China (No.2007AA01Z457);Shanghai Science and Technology Development Fundation,China(No.07QA14033)

摘　　要：When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes' upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems.When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes＇ upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems.

关 键 词：PEER-TO-PEER file sharing system service rate file transfer Zipf distribution asymptotic equality 

分 类 号：TP393.409[自动化与计算机技术—计算机应用技术] TP393[自动化与计算机技术—计算机科学与技术]