How-To: Build your own network firewall - Engadget

Network appliances don't always offer all the firewalling features a user needs -- you know, the advanced port blocking and security procedures we'd like to keep our little home network fiefdoms secure. In today's How-To we'll show you how to build a firewall out of an old PC with a live Linux CD and some spare ethernet cards. It's the perfect use for that machine with the dead hard drive (or no hard drive at all).

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