ISBN 0-7357-1099-6 Price £38.99 UK
Bob Ziegler with Carl B Constantine as the contributing author
and Joshua Jensen and John M. Millican as the technical reviewers.

Foreword, 13 Chapters, 4 Appendices and Index in 565 pages
 

Chapter List

    1     Preliminary Concepts Underlying Packet Filtering Firewalls
    2     Packet Filtering Concepts
    3     iptables:  The Linux Firewall
    4     Building and Installing a Standalone Firewall
    5     Firewall Optimisation
    6     Packet Forwarding
    7     NAT - Network Address Translation
    8     Debugging the firewall Rules
    9     Verifying that the System is Running as you Expect
    10   Issues at the UNIX System Administration Level
    11   Secure Shell - SSH
    12   Tripwire
    13  Intrusion Detection and Incident Reporting

            Appendix A
                Security Resources
            Appendix B
                Firewall Examples and Support Scripts
            Appendix C
                VPN
            Appendix D
                Glossary
           
            Index

Synopsis

    Network security and a reasonably good understanding of it is the thing that makes the internet work in the way that it is supposed to and also allows all those countless millions of internal networks around our small blue green planet to exist without too much of a hicup.    Bob Ziegler's second book about Linux Firewalls gives an excellent introduction to the world of iptables and what to do with it to keep your shopping list secure from prying eyes.  

Review

From the outset this second edition of Linux Firewalls which was written to cover the 2.4 series of GNU/Linux kernels is quite obviously a security bible.    From the front cover to the back cover the reader is given the kind of advice that is essential for a system administrator or network security person to have.  The book is aimed at home network users and small business network users but it's likely that the same methods could be used with larger networks.   Part of the introduction explains what the book doesn't cover.   "The security policies and procedures that a large business needs to emphasise.   .... and further  on ......  This book doesn't attempt to address issues of internal system security; large scale, multiuser LAN security; complex proxy configurations; corporate level authentication methods and technologies; encryption; or commercial level firewall and network architectures."  The rest of the book continues in a similar vain making sure that the reader is not misled into thinking that the writer might have made a mistake somewhere.  You might also want to have a look at  ....   http://www.linux-firewall-tools.com/linux/

Like most of the Newriders series of books about Linux this one is laid out in a way that helps the reader who is new to a particular subject to understand something without too much pain.   The writers own understanding of firewalls is that it helps to understand that there is a top part to a firewall script, a middle part and the end bit.   All of which have to be properly written with the correct syntax in order to make sure that a network is properly defended against an intruder.  There is certainly plenty of help for that kind of thinking in this book.  I was able to use the previous version to produce some reliable ipchains firewalls.  This volume has allowed me to produce some iptables firewalls which are still keeping out intruders many months after they were configured and built.

Important concepts that should be noted are available to the reader inside the front cover under a title of "Contents at a Glance" .   These are ......   Packet Filtering and basic security measures.  Such as an introduction to iptables and later on how to build and install a stand alone firewall.   Firewall optimisation, packet forwarding and network address translation come next followed by hot to debug the script that you just produced.  The latter part of the book goes into intrusion detection such as the use of tripwire and how and when to report an incident.  There is also short introduction to Secure Shell or SSH which is the backbone of the internet as far as the system administrator is concerned.  The appendices give useful info such as the various firewall scripts and security resources which might not be found by someone who isn't used to thinking in terms of network security.

This is an excellent example of what GNU/Linux or UNIX security should be about.  If you need to build a firewall or you want to know more about network security issues you should get hold of Bob's second book and read it from cover to cover.    If you are using a broadband connection from within the United Kingdom then you should be reading this book right now.

Review by Richard Ibbotson

Richard is the organiser for Sheffield Linux User's Group
– you can view their web site at – http://www.sheflug.co.uk.