内网代理服务器由于其IP地址是私有的,即使在已知其内网IP时,外部主机也无法通过传统代理模式连接到该代理服务器实现内网资源的访问。通过分析网络地址转换原理、认证和加密机制,提出一种可架设于专用网的代理服务器设计方案,通过完善代理认证凭证和加入P2P的数据传输机制,以保障代理服务器所保护的信息安全。 Intranet proxy server because its IP address is private, even in the known IP within the network, the external host can not connect to the proxy server through the traditional proxy mode to achieve intranet resources. By analyzing the principle of network address translation, authentication and encryption mechanism, this paper proposes a proxy server design scheme that can be set up in a private network. By improving proxy authentication credentials and adding P2P data transmission mechanism, the information security of proxy server is guaranteed.