Introduction BSD-Unix - what's that ? That's the question that crops up often when the name shows up. This lea\003et aims to give the most important answers, plus starting points to get you asking more questions that go deeper than this lea\003et covers. Many BSDs - One Philosophy Traditionaly one divides the group of UNIX operating systems in 2 groups: System V (\204SysV\223 for short) and BSD. The later originated at the University of Berkeley, California. Today' s BSD Systems are direct descendants from \2044.4BSD Lite2\223, the last of\002cial BSD version from Berkeley. The origins of BSD reach back to the 1970s, and the history is too complex to roll out here, but one can say: * There's over 30 years development work in BSD systems, in that the software has been continually revamped to mo- dern requirements, but without ever throwing out the en- tire thing and starting completely anew. As a result to- day BSD derivatives are mature stable Unixes without teething troubles. * Over time, multiple loosely coupled branches of BSD ha- ve evolved, each following their own objectives, but they remain very similar and through cross porting of interfa- ces, drivers and applications remain interchangeable. * Today , derivatives include: FreeBSD, NetBSD, OpenBSD, and BSDi; The later is a commercial variant. Other commercial derivatives are Mac OS-X from Apple and the completely open derivative \204Dar- win\223. BSDi, Darwin and MacOS aren't dealt with more here, for lack of space. * None of the BSDs is a \204Linux Distribution\223 - Linux and the BSDs are similar insofar as they use much of the same software, EG gcc etc.) but kernel, licence, and develop- ment models are markedly different. Similarities All BSDs have the following attributes and conditions in com- mon.BSD Licence The majority of the source code of the BSD operating systems is available under the standard BSD licence. In contrast to the GPL licence used by the Linux Kernel, BSD licences (there are several variants) allow distribution of binaries without accom- panying sources, which is important for commercial products, which are based on BSD code but for which companies want to release either no, or only partial sources. From One Mold Each BSD encompasses not just the kernel, but also a number of system libraries (libc, libpam...), user programs (ls, more, \002nd, sort, lpr...) and system administrator commands (ifcon\002g, chown, cron, dump, restore...) as well as build tools (gcc, ma- ke, ld) as the \204operating system\223, that should be regarded as a uni\002ed whole, and maintained as such. Upgrades apply to the whole operating system and not just to the kernel, (as with Li- nux). The entire operating system and the kernel can be rebuilt from the sources with just a few commands. (Recently Gentoo Li- nux has also offered similar capability, though without the other BSD advantages.) A strict separation between operating sy- stem and supplementary products (Apache, Netscape, OpenOf- \002ce etc) prevails, implemented in seperate source hierarchies. In consequence application programs can be updated separate- ly, which increases the longevity of installations. Professional Development All BSDs maintain their complete operating system source code in a CVS repository. Thus all changes can be reconstructed, reviewed and if necessary also reversed. A release engineering team controls the entire integrated product. Tight Organisation The BSD projects are not undisciplined heaps of code, in which many dabble, but form professional organisations similar to commercial software projects. Each has a \204Steering Commit- tee\223, called Core , which over-views programming sub projects etc. Around the core teams there are numerous sub projects of developers - called Commiters - responsible for addition andmaintenance of documentation and drivers, and all the other tasks of the projects. Software Galore ! All BSDs can compile and run over 99% of the source code software available from EG freshmeat.net, and there are usually also pre-built packages (Gimp, KDE, teTeX etc). ABIs (Application Binary Interfaces) allow Linux programs to run on the BSDs, even if there is only a binary package for Li- nux. Thus further programs can be run on BSD even if the latest version is only available for Linux, (EG Acrobat reader, Netsca- pe7, StarOf\002ce 6,0, Quake3 etc.). There's no noticeable speed degradation. The quality and functionality of the Linux ABIs is however not equally well developed on all BSDs - FreeBSD has the most functionality. Stable File System The UFS \002le system has been highly valued for years and offers very high performance, by use of Softupdates the integrity of the meta data is is guaranteed in event of a crash. Ports System Much free software is only available in source format, or has licencing restrictions on distribution in binary Package format, (the BSD equivalent of Linux RPMs). The Ports Framework covers such contingencies. It consists of a hierarchy of Make\002- les and where necessary patches, which unpack generic source packages, compile and install them. The Ports System can on its own fetch and apply sources and binaries from the Internet, or from CDROM, including building and installing any depen- dencies. Individual BSDs In Detail: FreeBSD On normal PCs (often called x86 or i386-Hardware) FreeBSD is the most frequently encountered representative of the BSD family. This is probably because it offers the broadest hardware support for this platform, and is best optimised for it. Also it tends more than the other two to \204functional comfortable-ness\223 4,5,0as experienced on other desk top systems. Thus it is more at- tractive for newcomers, also offering the biggest collection of ported software, with nearly 8000 packages. FreeBSD no lon- ger regards itself just as a pure server system for skilled admi- nistrators, but aims itself also at end users, particularly new- comers from Windows and Linux. FreeBSD 5.0 (released Jan 2003) now supports a variety of computer architectures: alpha (DEC's Alpha/AXP), i386 (Intel and AMD, pentiums etc), ia64 (Intel's Itanium), pc98 (Japanese PCs), sparc64 (Sun's UltraS- parc. Power PC and StrongARM ports are in progress, but not available yet. FreeBSD alone of the three offers matured SMP multi processor support. NetBSD NetBSD is about as old as FreeBSD. Its most outstanding cha- racteristic is the ever growing number of hardware platforms it supports - far more architectures than any other operating sy- stem. A complete list would the exceed space available in this this lea\003et, and would quickly be incomplete and obsolete so refer to the NetBSD web page. In many cases the decision to go NetBSD is easy, as it's the only one available which runs on the hardware. If one has such exotic hardware, that none of the three BSD systems run on it so far, the chance is greatest with NetBSD that a port can be achieved with acceptable effort. Alt- hough not much older than FreeBSD, NetBSD happily portrays itself as the \204big brother\223 of open source BSDs. It tends more than the other two to maintain traditional BSD characteristics. This conservative behavior also has quite a positive, compensa- tory effect on the other BSD systems. OpenBSD OpenBSD split from NetBSD in 1996, and so is by far the youn- gest of the three. Although it inherited a lot of platform-ports from NetBSD, some of the rarer platforms have become stunted due to lack of resources. \204OpenBSD's\223 motto and primary goal is \204Security\223. Though FreeBSD and OpenBSD have also not neglected this, it's where OpenBSD shines. This doesn't mean that OpenBSD is a \204Secu- rity Software Stew\223, rather \204Security\223 in OpenBSD also means Correctness. The team around Theo de Raadt has performed a complete line by line source code audit of the operating systemto weed out any bugs and detect and remove possible vulne- rabilties. (Naturally FreeBSD and NetBSD also pro\002ted from this, as appropriate corrections were adopted, where appropria- te). OpenBSD's support for security also means extensive sup- port for cryptography. Prominent here is the unique support for several hardware crypto accelerator cards and the broad integra- tion of strong cryptography in the OS. As Theo de Raadt lives in Canada, these algorithms are not encumbered with export re- strictions. UNIXRfl is a registered trademark and The Open GroupTMis a trademark of The Open GroupTMin the USA and other countries. All other marks and names are property of their respective owners; all appropriate registered trade marks and registered trade marks are recognized as such; their use serves only identi- \002cation purposes.BIM \226 Berkeley in Munich presents: BSD BERKELEY SOFTWARE DISTRIBUTI ON In this lea\003et we try to give you an overview of the three open source representatives of the family of BSD UNIXRfloperating systems: FreeBSD http://www.freebsd.org/ NetBSD http://www.netbsd.org/ OpenBSD http://www.openbsd.org/ Deutsch Uebersetzung auch erhaltlich: http://www.berklix.org/bim/lea\003et/ cfl BIM, http://www.berklix.org/bim/ Jan/2003. All info unguaranteed. Format: LATEX 2eon FreeBSD 4.7 Print: dvips / ps2pdf Prepared/ Printed in Germany - Imprim\351 en Allemagne