防火墙是Internet上公认网络存取控制最佳的安全解决方案，网络公司正式将防火墙列入信息安全机制。防火墙是软硬件的结合体，架设在网络之间以确保安全的连接。因此，它可以当作In－ternet或Intranet的网关器，以定义一个规则组合或安全政策，来控制网络间的通讯。并可有效率 Firewall is recognized as the best Internet access control security solutions, Internet companies officially included in the firewall information security mechanism. Firewall is a combination of hardware and software, erected between the network to ensure a secure connection. As a result, it acts as a gateway to an In-ternet or Intranet to define a combination of rules or security policies to control the communication between networks. And can be efficient