【摘要】 讨论了当前计算机网络发展的热点技术：虚拟专用网（ＶｉｒｔｕａｌＰｒｉｖａｔｅ　Ｎｅｔｗｏｒｋ）。论述了用虚拟专用网来组建新的Ｅｘｔｒａｎｅｔ安全体系结构，从而带来更好的网络性能和应用前景。更多还原

【Abstract】 The thesis depicts a hot technological point of the computer network: That is virtual private network. also called VPN. WithVPN we can constructure the new extranet’s security architecture. in result, and can acquire better performances of the network as well asprosperous applications.更多还原