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Linux Resources

Recommended Linux Books

We recommend these Linux books, based on the reviews or personal experience. The rating is from 1 to 5 stars.

Port Usage

Compute Sunrise, Sunset & Twilight For Cities & Airports Worldwide With Local TZ is a non-profit web site with lots of information on Linux. In July of 2001, interviewed Bob Toxen, author of Real World Linux Security. They also have featured the first edition of our book. provides list of what TCP, UDP, and ICMP ports are used for, both proper usage and evil usage; rest of site is in German on security.

Web sites operated by several leading Internet security organizations are vulnerable to an old but serious security flaw known as the cross-site scripting (CSS) attack.

Linux Today is one of the best sources for up to date information on general Linux topics. It links to Linux news coverage from other web sources, as well as having some extensive coverage about Linux on it's own. It is one of the best places to receive security related updates for all distributions of Linux.

Slashdot is one of the grand-daddies of Linux sites on the net. It has news about Linux, programming languages, and other stuff that geeks might think is cool. Stories about Lego Mindstorms, Space Stations and satellites, and other interesting stuff might pop up. Slashdot has a very active user community that makes it a good place to ask questions. Slashdot also hosts a BSD community.

Linux Weekly News (/ is a great place to get a digest of activity in the Linux community. It is well organized and edited. There are always stories and news about each popular Linux distribution, as well as status reports about what development is happening on the Linux kernel, as well as all security reports that occurred during the week.

Linux Laptop Guide ( gives lots of information on running Linux on a laptop, PDA, or wearable computer. is the Atlanta Linux Enthusiasts group, a non-profit group based in Atlanta, Georgia, USA that meets monthly and helps both Newbies and experienced Linux people with problems, new capabilities, security, etc. Bob gave a presentation on Linux security at the May meeting. lists some of the many applications that people "need" Windows for that are supported under Linux. If these are what you use Windows for you may be happier on Linux. defines many Linux terms in terms of Windows terms. gives some statistics (August 2001) on the rapid growth of Linux in the Information Technology (IT) Departments of mainstream companies. There now is 1 Linux server for every 5 Windows servers. Many claim that that 1 Linux server will do the work of 2-5 Windows servers with one half to one fifth the SysAdmin time and dollar cost and a small fraction of the crashes and security vulnerabilities and needed security patches. is the SANS Institute's top 20 vulnerabilities on Linux, Unix, Windows, and other systems. These are the ways most likely to be used to break into your systems.

It is important to understand that SANS lists the top Windows vulnerabilities and the top Linux/Unix vulnerabilities. This does not mean that they have equal security levels! The only ranking is that the #1 Windows vulnerability is more critical than the #2 Windows problem and the #1 Linux/Unix problem is more critical than the #2 Linux/Unix problem, etc. provides a complete guide to hosting a keysigning party to allow the participants to sign each other's PGP or GPG keys. It is suggested that this be done periodically at meetings to expand one's web of trust.

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