The PIX box uses NAT and high-level encryption for the ultimate in firewall protection. Every network is susceptible to security breaches and unauthorized access from external as well as internal sources. Sensitive data must be protected, not only from users within the network, but from outside users as well. The network security concerns of all organizations expanding their internal networks and connecting to the Internet must be addressed. Of considerable concern is that unauthorized access to information within a network may go undetected, particularly if the unauthorized user or hacker does not alter the network or its data.
Ultimate security is to disconnect from the network.
However, for companies who wish to exploit the commercial potential of the Internet and in so doing get closer to their customers and bring together remote corporate sites and employees, this is not an option.