Everyone's jumping on the Internet bandwagon today, but with the explosive growth of the Internet has come a corresponding explosion in attacks on connected computer systems. These range from familiar attacks (e.g., cracking passwords and exploiting security holes in operating systems) to newer and more technically sophisticated ones (e.g., forging IP source addresses, packet sniffing, and hijacking terminal or login sessions). How can you protect your site from these threats? How can you help your users get what they need from the World Wide Web and other Internet services, while protecting your systems and networks from compromise? Internet firewalls are currently the most effective defense. . Building Internet Firewalls is a practical guide to designing, building, and maintaining firewalls. It isn't a theoretical tome on security concepts; it's a down-to-earth, highly detailed handbook for real-life system administrators, and managers - and for anyone who wants to learn what firewalls can (and cannot) do to make a site secure. If you're planning to build your own firewall, this book will tell your how to do it. If you're planning to buy one, this book will give you the background information you need to understand the protocols, technologies, and features of the products you'll be considering.