FWTK是一套用来建立和维护内部网络防火墙的工具集，用于构建应用网关式防火墙。它包含了许多独立的组件，大部分的组件是代理应用程序，如telnet、FTP、rlogin、sendmail、HTTP、X windows等。和squid、socks等软件相比，它的突出优点是将很好的访问控制融入其设计中，不但可以从本地和目标地的主机名、IP地址来指定访问规则，而且可以根据访问操作来允许或拒绝某个执行命令，更充分地体现了应用层网关的优势。 -FWTK is a set used to create and maintain the internal network firewall tool set, used to build the application gateway firewall. It contains a number of independent components, most of the components is the agent applications such as telnet, FTP, rlogin, sendmail, HTTP, X windows, etc.. And squid, socks and other software, it will highlight the advantages of good access control into their design, not only from the local and target host name, IP address to specify the access rules, and can be operated under the Access to a permit or refuse to implement orders, more fully embodies the advantages of application layer gateways.