基于NS2的P2P网络模拟平台研究

Research on NS2-Based P2P Network Simulation Platform

目前模拟(Simulation)在Peer-to-Peer(P2P)系统的评估和分析中发挥着重要作用。很多研究者认为底层网络布局对P2P系统性能有较大的影响,但现有的模拟器多基于不考虑底层网络的简单模型。同时多数模拟器仅支持特定协议的较小规模模拟。上述缺陷导致使用现有模拟器进行模拟的实用性和真实性无法满足实验需求。为解决上述问题,一种基于NS2的通用的、可扩展的P2P模拟平台NDP2PSim得以提出。该平台可为各类P2P协议的模拟提供真实且通用的模拟环境,同时实现了P2P系统的一些通用功能并以模块形式提供以便于使用。介绍了该模拟平台的系统结构和实现细节,并模拟Freenet作为实例演示系统使用情况。

Nowadays simulation plays a vital role in the evaluation and analysis of peer-to-peer systems. Although many researchers point out that the underlying network highly impacts the performance of peer-to-peer systems, most existing simulators are still based on some simplified models without consideration of the underlying network. Meanwhile, most simulators can only support the simulation of some specific protocols on small scales, which leads the simulation environments provided by these simulators to departure from real systems. An integrated and generic simulation platform, NDP2PSim, built on NS2 was designed and developed. This platform can provide a realistic and generic simulation environment for almost all kinds of existing P2P protocols on a large scale. And some common functions of P2P systems are also abstracted and provided as modules in order to make the platform easy to use. The structure of NDP2PSim was described in detail and the analysis and comparison with other existing simulators were given.