For each of these catagories, a separate list of rules is maintained. It should be noted that when combined with various other firewalling technologies including fwtk it can create a very robust, secure, firewall device. It is important to mention that it unto itself is a very flexible single technology firewalling solution. When combined with fwtk which operates at the application level it becomes even more powerful.
Traditional routers are vulnerable to different kinds of attacks.
Somebody who has access to machines on the Internet, in any fashion, can gain unauthorized access to your systems in a multitude of ways. It is also possible for such a person to destroy or alter at will any unprotected areas of your network. Source Routing, where a intruder mimics an IP packet comes from a trusted system. It can explicitely deny specific hosts from accessing services as well as trusted hosts from accessing untrusted sites. By directing flow of ip packets be it tcp, udp, icmp it can control the flow of data in any direction customized depending upon your specific needs.