Red Hat Linux Firewalls

A book for those familiar with RedHat Linux and especially those into Network/System administration. It focuses on two popular firewall software for Linux: ipchains and iptables. But, it does not dwell straight into configuring or setting them up; instead it talks about the basics first. It starts with firewall definitions and TCP/IP basics, covering IP addresses, DNS, TCP/IP headers, tools and configuration. The examples, tools and configuration are specific to RedHat Linux. A chapter on Internet Services explains methods to identify the type of traffic that flows in your network. The connection state, source and destinations ports and TCP flags of various TCP/IP services and apps are summarized in tabular form. This is handy to allow/block traffic based on the information in the packets. 

It also talks about types of firewall architecture, design and related terms like Proxying, NAT (Network Address Translation) and VPNs (Virtual Private Networks). It also explains configuring the firewall using graphical utilities like lokkit and gnome-lokkit. It devotes only one chapter on ipchains and covers the latest and more powerful iptables in details. It goes on

to explain the basic and advanced firewall setups: NAT, packet forwarding, masquerading, transparent proxying and screened firewall setups. 

S N   A   P   S   H O   T Price : Rs 239 Author : Bill McCarty Pages : 523 Contact : Wiley Dreamtech India, Delhi.  E-mail : wdt@vsnl.net  Tel : 23260877, 23270877.

Then there are chapters on testing, troubleshooting and administering firewalls where you are introduced to various tools and techniques. The book has useful appendixes which list security related web sites, protocols, ports and services that can be used as a reference to identify and block network traffic. There is an appendix that talks about setting up a basic VPN on Linux using open source software. 

A must read for those looking for a book on Linux firewalls especially iptables. To work with the examples in the book, you will require an installation of RedHat Linux 7.0 or above. The book does not bundle any RedHat distribution CDs. 

Shekhar Govindarajan