From the title it may seem that Personal Firewalls for Administrators and Remote Users was written for administrators and users of business networks. However, as more people take advantage of "always on" Internet connections, they are becoming de facto administrators. Remote . . .
From the title it may seem that Personal Firewalls for Administrators and Remote Users was written for administrators and users of business networks. However, as more people take advantage of "always on" Internet connections, they are becoming de facto administrators. Remote users are no longer only connecting to work from their home or a hotel room. Computers and wireless connections can now be found at schools, the local library, and the corner coffee shop. Unfortunately, as access has grown, so have the associated risks. Personal Firewalls for Administrators and Remote Users covers personal firewalls as a means to mitigate some of that risk. Lisa Yeo has also included security and networking basics, log reading and troubleshooting. While ipchains and iptables are mentioned, Linux firewalls are far from the main focus. Nonetheless, the book is well written and clear. Figures and tables are frequently used to clarify the author's point, but are not overused.

The first two chapters on security and networking basics are a primer of essential information for any technical discussion of firewalls. You may already be familiar with the information presented in these chapters and choose to skip past them. However, they are a brief and easy read. The detail was sufficient to keep me interested, but not so great that it would cause a novice's eyes to glaze over. It makes good foundation for the chapters that follow, establishing working definitions and a common viewpoint for the author and reader.

While the other chapters are very useful and add value, I found the section on personal firewalls to be particularly well crafted. As one would expect, Network Address Translation (NAT), packet filtering, stateful inspection and application proxy are discussed, as well as blocking on attack signature and intrusion detection. Each approach is described in an easy to understand manner. Diagrams are included to illustrate the process. The author explains how each method is implemented in personal firewalls, and where they fit in the design of a secure environment. She gives advantages, disadvantages, and examples of products using the particular method. A few example ipchains and iptables rules are provided, as well as listing Linux based application proxies and intrusion detection systems. Even though most methods can be implemented with "built-in" capabilities of Linux, the examples frequently involve add-on software.

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