Computer systems are threatened by external dangers, such as viruses, worms, and other malicious computer programs. FIG. 1 illustrates a block diagram of the software portions of a computer system, including end point vulnerabilities. The elements 110 typically reside in the operating system or in applications installed on a machine. The operating system and other resources 120 and the Internet applications 130 interface to the outside world through the TCP/IP stack 140.
A malicious individual or program can access the operating system or other resources 120, through the TCP/IP stack 140. Vulnerabilities in the operating system can enable others to obtain confidential information from the computer system, or use the computer system to attack other systems.
Traditional firewall applications 150 are an interface between the TCP/IP stack and the outside world. They attempt to prevent unauthorized access to the computer system. However, they do not address all of the threats that endanger computer systems.