Network break-ins have increased as the network has grown and become more impersonal, but it is easy to exaggerate the extent of these security breaches. Over-reacting to the threat of break-ins may hinder the way you use the network. Don’t make the cure worse than the disease.Firewalls can do a lot for your site’s security. In fact, some advantages of using firewalls extend even beyond security, as described below.
Think of a firewall as a choke point. All traffic in and out must pass through this single, narrow checkpoint. A firewall gives you an enormous amount of leverage for network security because it lets you concentrate your security measures on this checkpoint: the point where your network connects to the Internet.
As we’ve mentioned, firewalls are a very effective type of network security. This section briefly describes what Internet firewalls can do for your overall site security. Firewall Design describes the various types of firewalls in use today, and the other chapters in Part II describe the details of building those firewalls.
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