Secondly,Read and analyze Gnutella, Freenet, Skype agreement, build the experiment environment to grasp the Gnutella, Freenet, Skype correspondence data, discovere the agreement characteristic and some safe weaknesses within mechanisms.

• 12) 阅读并分析Gnutella，Freenet，Skype的协议，搭建实验环境对Gnutella，Freenet，Skype通信数据进行抓包试验，发现了协议特征和运行机制中的一些安全弱点。