FreeBSD: Meaning (information, definition, explanation, facts)

FreeBSD is a Unix-like operating system descended from Unix via the BSD branch through 386BSD and 4.4BSD. It runs on processors compatible with the Intel x86 family, as well as on the DEC Alpha, the UltraSPARC processors by Sun Microsystems, the Itanium (IA-64) and AMD64 processors. Support for the PowerPC architecture is in development. It is generally regarded as being quite reliable and robust.

History and development

Initial development of FreeBSD was started in 1993, and took its sources from 386BSD. However, due to concerns about the legality of all the sources used in 386BSD, FreeBSD re-engineered much of the system with the FreeBSD 2.0 release in January of 1995 using the 4.4BSD-Lite release from the University of California, Berkeley. The FreeBSD Handbook includes more historical information about the genesis of FreeBSD.

The current (February 2004) FreeBSD release is FreeBSD 5.2.1.[1] FreeBSD developers maintain (at least) two branches of simultaneous development: a -STABLE version of FreeBSD, which produces releases about once every 4-6 months. The latest STABLE release of FreeBSD is 4.10. The other development branch, -CURRENT, contains aggressive new kernel and userspace features. At the time of writing, the 5.x release series is cut from the 5-CURRENT branch, but has already produced 5.2-RELEASE. The FreeBSD development team has announced that the 5-CURRENT branch will become 5-STABLE around 5.3-RELEASE, at which point a 6-CURRENT branch will be created.

FreeBSD 5 includes a number of new features, including many that are security related. The TrustedBSD project was formed for the express purpose of adding trusted operating system functionality to the FreeBSD operating system. An extensible mandatory access control framework (the TrustedBSD MAC Framework), filesystem Access Control Lists (ACLs) and the new UFS2 filesystem all came from TrustedBSD. Some of the TrustedBSD functionality has been integrated into the NetBSD and OpenBSD operating systems as well. FreeBSD 5 also has support for encrypted filesystems, through the GDBE system written by Poul-Henning Kamp. [2] Other major FreeBSD 5 functions are related to more finely grained in-kernel locking to improve SMP performance, and a m:n (kernel:userland) threading solution called KSE which will be the default threading (pthreads) library, starting with 5.3.

The FreeBSD ports system provides a consistent way of installing software ported to FreeBSD. It uses Makefiles laid out in a directory hierarchy, so software can be deinstalled and installed with the make command. Precompiled (binary) ports are called "packages", and are available for download.

FreeBSD is released under the BSD License, which allows everyone to use and redistribute FreeBSD as they wish, as long as they do not remove the copyright notice and the BSD license itself (which does not prohibit re-distribution under another license).

• A derivative version based on the GNU toolset is currently being developed by Debian as Debian GNU/FreeBSD.
• DragonFly BSD is a fork from FreeBSD 4.8 that is intended to be the logical continuation of the FreeBSD 4 series. It will feature a threaded message passing system similar to that found in microkernels.
• The FreeSBIE project is producing live CD distributions of FreeBSD, similar to the Knoppix distribution of Linux.
• Frenzy is another FreeBSD based live CD, mainly oriented towards Russian speaking users.
• BSDeviant is a live FreeBSD distribution that can fit on one Mini CD-R.
• PicoBSD is a one-floppy version of FreeBSD.
• Darwin borrows heavily from FreeBSD.
• m0n0wall is a FreeBSD based embedded firewall package.

• Absolute BSD, The Ultimate Guide to FreeBSD. Michael Lucas. No Starch Press, July 2002. ISBN 1886411743.
• BSD Hacks, 100 Industrial-Strength tips for BSD users and administrators. Dru Lavigne. O'Reilly, May 2004. ISBN 0596006799.
• The Complete FreeBSD, 4th Edition, Documentation from the Source. Greg Lehey. O'Reilly, April 2003 ISBN 0596005164.
• The Design and Implementation of the FreeBSD Operating System. Marshall Kirk McKusick and George V. Neville-Neil. Pearson Education. ISBN 0201702452. Expected availability August 2004.
• The FreeBSD Corporate Networkers Guide. Ted Mittelstaedt. Addison-Wesley, December 2000. Paperback, book & CD edition, 401 pages. ISBN 0201704811.