SPECIFICATION OF BSD OS

Initially, many thought that NetBSD would just serve as an interim 386BSD release in the growing time span between "official" 386BSD releases. As time went on, and it became increasingly obvious that there would be very little if any development from Jolitz and the 386BSD group, NetBSD gained notoriety as an operating system in its own right. Other developers began working on porting NetBSD additional platforms such as the Macintosh, Atari ST, Amiga, and PC platforms. The focus of NetBSD became portability and University/Academic research. Today, the NetBSD ports page reports some level of support for over 50 different platforms including, among others: Intel, Macintosh, Playstation2, and even Sega Dreamcast. This dedication to portability has been a "God-send" to many in the computer science research community. Not only do students and researchers get their hands on a full-fledged, opensource operating system, they also gain the ability to develop exciting new technologies on low cost or free equipment long since thrown aside as useless. These new technologies then often find their way into other opensource operating systems such as FreeBSD, OpenBSD, Linux, and now Darwin/Mac OS X.
FreeBSD:

FreeBSD continued the tradition of supporting the i386 platform set down by 386BSD. Though FreeBSD has been ported to the Alpha processor, it is primarily focused on developing a highly optimized version of BSD for the Intel/AMD platform. In 1992, Jordan Hubbard (who is now employed by Apple) and his colleagues began working with 386BSD and they soon released their changes through a patchkit referred to as the "Unofficial 386BSD Patchkit." Based on these patches and the underlying 386BSD operating system, David Greenman, then at Walnut Creek, suggested that this group produce their own BSD. FreeBSD was born. The first 1.0 distribution of this new operating system was released in December 1993. Walnut Creek prepared the CDROM distribution channel for the OS, and even offered their own high bandwidth servers as FTP sites. Just as NetBSD was required to upgrade to 4.4BSD-lite upon settlement between Novell and BSDI, so was FreeBSD. Hence, FreeBSD 2.0 was released in November of 1994.

From the beginning, another focus of FreeBSD was the less computer literate user. While NetBSD appealed to the "techie," FreeBSD attempted to make the install process and system maintenance as simple as possible through the use of scripts, and CDROM distributions (similar to what Linux attempts to do today). Further, the FreeBSD Ports Collection, now modeled by the other BSDs, makes porting third party, opensource applications relatively simple and system administration that much easier. Also as Linux gained in popularity, FreeBSD has tried to remain competitive through the inclusion of a Linux emulation mode. Today, the FreeBSD user can run just about any compiled Linux program on FreeBSD without worrying about recompiling the code for FreeBSD.

Another point of interest not just for FreeBSD, but for NetBSD and for OpenBSD as well, is their development model. In today's world of opensource software, the variability in development models is astounding. Many projects function as the Linux kernel project does: developers answer to one person who decides whether something stays or goes. In the case of the Linux kernel, when a developer wants to add a line of code, he or she must pass that code to Linus Torvalds who then decides whether he likes the code the developer wants to add. Although in principle this sounds like a good way to keep the kernel nice and clean, in practice it is becoming increasingly difficult for one person to handle such an arduous task. The modern BSDs use a very different development model from that of the Linux kernel model. FreeBSD has a committee of 200 developers called the "Committers" whose members are the only ones allowed to make changes to the FreeBSD source tree at any time. In NetBSD, this committee is referred to as the "Port Maintainers." Further, a Core Team selects the Committers and arbitrates disputes governs these BSD distributions. Thusly, this Core Team acts as a board of directors. Beginning in October 2000, the FreeBSD Core Team became an elected body whose members are elected from and by the population of the Committers.
OpenBSD:

OpenBSD is considered by many to be one of the most secure operating systems in existence. From its inception, OpenBSD has focused on making BSD as secure as possible. As stated on the OpenBSD web site, the developers' "efforts emphasize portability, standardization, correctness, proactive security, and integrated cryptography" and OpenBSD can also boast "four years without a remote hole in the default install." How can Theo de Raadt, the lead developer of OpenBSD, claim such a record? The OpenBSD story began in 1995 when OpenBSD first diverged from NetBSD due to a disagreement between Theo de Raadt and the NetBSD core team concerning the future development of NetBSD. OpenBSD 2.0, the first release of this new operating system, was released in October 1996. Since Theo is from Canada, he was able to take advantage of his Canadian residency and include, throughout the operating system, advanced cryptography forbidden by United States export laws. For example, the Blowfish algorithm is used to automatically encrypt user passwords. In addition to the strong cryptography included in OpenBSD, the entire source base of the distribution has been audited line-by-line in order to find any potential holes. This audit not only produced a more secure operating system, it also removed many of the programming hassles and bugs plaguing BSD-derived operating systems since the 1970's and 1980's.

Since OpenBSD was originally derived from NetBSD, it shares much of the portability for which that system is so well known. Though it does not support the 50+ platforms supported by NetBSD, it does support such platforms as i386, PowerPC, m68k (pre-ppc Macs), Alpha and several more. Even more importantly though, many of the changes made to OpenBSD to improve the robustness and the security of the operating system have "trickled down" to other BSD-derived systems like NetBSD, FreeBSD, and even Darwin/Mac OS X. As work on this operating system continues, new advances in secure systems design are being made.
Darwin/Mac OS X:

To many, Darwin/Mac OS X is the "fifth BSD", and should therefore be included in any discussion concerning BSD. Further, with the Dawin FAQ Apple states "that apart from a few architectural difference (such as our use of the Mach kernel), we try to keep Darwin as compatible as possible with FreeBSD (our BSD reference platform)." With such a statement, Apple has begun to gain a sizable following among both the BSD community and the Linux community by proving their ability to put a UNIX-based operating system on the desks of even the most computer illiterate. Without repeating much of what I have written in my previous article, it is an exciting time to be a Mac enthusiast as now we can draw from this very rich history by joining the "BSD club."

The future looks bright as people in all BSD and Linux areas consider what is next for Darwin. After all, now that Apple has opensourced their operating system, others have a real say in how the operating system evolves. People are working on advanced journaled file systems, distributed file systems, and clustering tools. Of particular interest is a recent announcement by the Secure Trusted Operating System Consortium (STOS) in which they say they want to "give the BSD-based operating system, Darwin, the features and capabilities of a trusted operating system." You can bet that as Darwin/Mac OS X matures, Apple will look at and potentially integrate these advancements whether they come from a dedicated project like the STOS or from something added to Net/Free/OpenBSD.

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