Steve Suehring - Linux Firewalls

Linux Firewalls, Third Edition By Steve Suehring, Robert Ziegler ............................................... Publisher: Sams Publishing Pub Date: September 14, 2005 ISBN: 0-672-32771-6 Pages:

An Internet-connected Linux machine is in a high-risk situation. Linux Firewalls, Third Edition details security steps that any sized implementation from home use to enterprise level might take to protect itself from potential remote attackers. As with the first two editions, this book is especially useful for its explanations of iptables, packet filtering, and firewall optimization along with some advanced concepts including customizing the Linux kernel to enhance security.The third edition, while distribution neutral, has been updated for the current Linux Kernel and provides code examples for Red Hat, SUSE, and Debian implementations. Don't miss out on the third edition of the critically acclaimed Linux Firewalls .

Copyright 2006 by Pearson Education, Inc.

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Library of Congress Catalog Card Number: 2004098792

Printed in the United States of America

First Printing: September 2005

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DEVELOPMENT EDITOR

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MANAGING EDITOR

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INDEXER

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PAGE LAYOUT

Julie Parks

To my wife, Rebecca

Steve Suehring is a technology architect with a diverse set of skills. He works with a wide array of technologies, from mainframe OS/390 through Microsoft Windows to several distributions of Linux. He has written a book on MySQL and numerous magazine articles. During his tenure as an editor for LinuxWorld Magazine , he focused on advocacy of Linux and open-source software, as well as computer security. He wrote a cover story for LinuxWorld Magazine featuring the WilliamsF1 team's use of Linux to design their Formula 1 car. Suehring is also a Cisco Certified Network Professional (CCNP), and he has contributed, according to him, "extremely small bits of code" to some open-source projects and lurks on a number of mailing lists, helping and answering questions when he can.

Robert Ziegler is a renowned firewall architect and consultant who has worked for a variety of organizations, including Nokia's router and access groups. He is well known as the author of the two previous editions of Linux Firewalls , and he operates a respected firewall resource site to share his design skills and evaluations of tools.

Thanks first to my family for being supportive while I write seemingly every day. I'd also like to thank my agent, Laura Lewin at Studio B, for all of her hard work and her constant help. Thanks also to A.J. Prowant for doing the technical edit on this project.

Chris and Nikie Tuescher deserve an acknowledgment for being great friends and understanding why we haven't come to Minneapolis latelythese books take time to write! Thanks to Aaron & Jodi Deering for having us over and for Aaron taking it easy on me at basketball. Thanks to Duff Damos for his continued friendship throughout the years. Pat Dunn, thanks for changing your password all the time and then forgetting it. Thanks to meek for his patience and constant help.

Here's the list, in no particular order. Though it maybe isn't readily apparent exactly how some of you helped, you have, in some way, contributed to this book (for better or worse). Andy Hale (let me know when you want to start fixing your floors), Dan Noah, Jim & Amy Leu, Kent & Amy Laabs, Michael Mittelstadt, Denise Sandell, The Pflugers, AWRC, Jake Buchholz, Richard Dean Anderson, Aaron Schrab, Beez, Rysch, HFB & The #JBS, The Guthries, The Heins, Tim McKeown, Pearl & Moff, Rob Konkol, Erin Thomas, Paul, Darrick, Jeff Sanner, Edward Van Halen, Peter DeLuise, The DBAs and the Data Architect team, Sarah Hagerman, Jay & Deb Schrank, Brian Page, Is Anyone Still Reading This, Mark Little, Nightmare Squad, Jim Oliva, John Eckendorf, 90fm, Scott & Karla Kluck, Amanda Tapping, The Steffens, Eliot Irons, Keith Imlach & the Data Security team, No, seriously, is anyone reading this, Sue Crawford, Erich Hartman, Commas are my best friend, Ron Mackay, The Chasteens, Darrin Davisson, If you haven't seen your name yet wait until my next book, Justin Hoerter, John Hein, Andy Berkvam, The Internets, Mike Wrzinski,, That was an extra comma because I love them so much, Chris Judge, Tony Falduto, Steve Hannan (I just thanked a Project Manager), Greg Rubey, Ryan Anderson, Suzi Limberg, Kevin Blake, Dave Dahlke, I get paid based on how many people I thank, Michael Shanks, Tom Lindley, This Space For Rent, Kevin Bedell, James Turner, Dee-Ann LeBlanc, Neil Peart, Norm & Crew @ Music Quest.