The main purpose of this thesis is to realize a packet forwarding gateway server based on TCP/IP in the UNIX environment, which is able to help CERNET users access the Internet transparently.

• 实现基于UNIX服务器和TCP/IP协议的,具有动态数据包转发功能的网关服务器,来透明代理用户接入Internet,是本文课题研究的主要目的。