Firewalls

Firewalls are one of the most important components in an enterprise network, yet they are frequently ignored and misunderstood by most developers. The main purpose of the firewall is to keep malicious people out of your network while still allowing your internal users to access the Internet and allowing external users to access various parts of your network. Figure 26.8 shows a typical firewall setup.

Figure 28.8. A firewall blocks most incoming connections, but usually allows outbound connections.

Firewalls vary tremendously in capabilities, but there are some common capabilities, and also some common network configurations. Many firewalls ...

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