一种基于流特征的P2P流量实时识别方法

A New Method on P2P Traffic Identification Based on Flow

P2P应用近年来取得了飞速的发展,P2P应用在推动Internet发展的同时也带来了大量占用可用带宽和网络安全等问题.由于P2P采用了动态端口等技术,使得传统的端口映射的方法对P2P流量的识别不再有效.如何有效地监测和控制P2P流量是网络测量领域一个重要的研究课题.与C/S(客户/服务器)网络结构不同,在P2P网络系统中,每个节点扮演服务器和客户机的双重角色:既向别的节点主动发起连接,又提供监听端口让别的节点连接;既从其它节点下载数据,又向它们提供着上传.基于上述事实,从五元组的流信息中提取出联入连接和联出连接,上行流量和下行流量两个特征.根据这两个特征设计并实现了一种实时的P2P流量检测方案.在方案的设计中,解决了主动连接和被动连接判定的难点.

P2P（Peer-to-peer） technology is a new communication model. It is developing rapidly in these years, and widely used in the sharing of network resources, instant communications, etc.. While P2P is promoting Intemet＇ s development, it is also bringing about many issues such as too much bandwidth occupying and network security problems. Since more and more P2P applications are using dynamic random port numbers, the traditional port matching technology is becoming useless. Being different from the C/S （Client/Server） structured networks, in a P2P network, each peer is playing both the server and the dient dual roles. While it initiates connections to other peers, it aiso opens listening ports for other peers connecting to it. Besides, while it downloads data from other peers, it uploads at the same time. Basing on these facts, this paper designed and implemented a new P2P traffic detection technology based on flow characteristics.