Chapter 12. Understanding Firewall Fundamentals

A firewall in a race car is designed to separate the engine compartment from the driver so that in the event of a problem the driver can be protected from what goes on in the engine compartment. A firewall on a computer network is very much the same concept, and that is to separate one portion of the network from another.

Complete separation means that no network connectivity exists, which does not serve anyone very well. By allowing specific traffic through the firewall, you can implement a balance of the required connectivity and security. Traffic ...

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