Cisco路由器访问控制列表配置实现第一道网络安全屏障

随着Internet的日益普及，网络安全、通信效率等是亟待解决的问题。路由器是网络通信中的结点，除了路径选择主要功能外，还有一个重要的功能：防火墙功能。访问控制列表可以使路由器对进出网络的IP报文进行分类和过滤。通过对访问控制列表实际应用的详细介绍以及一个用访问控制列表控制服务器访问的应用实例的配置，找到了一个很好解决网络安全的办法。在没有配置防火墙的网络，通过它，我们可以构建第一道网络安全屏障。

Realization of the First Phase of Network Security Barrier by Using Access Control List on Cisco Router

With the gradual popularization of Internet,network security and communication efficiency are the questions which we need to resolve urgently. Routers are the knots of network communication. Besides the major function of route choice,routers also play an important role:firewall. Access control list is a technique for classification and filtration of packets through routers. By introducing applications of ACL and configuring an instance of service access,we can find a good solution for network security:We can construct the first phase of the network security barrier by using access control list for those networks without firewalls.