BSD, one of the two original variants of Unix, has been reborn without proprietary code into a basketball team of Unix operating systems. Like Linux, BSD follows the Unix philosophy for OS and environment. Unlike Linux, each version has significant differences from the others, following different paths of specialization. The BSD OSs also cover different ranges of processor architectures - from 3 for FreeBSD to more than 30 for NetBSD.
For anyone looking at or using Linux, one of the BSD versions may suit you better. This column gives an overview of the different versions with links for more information. In some cases it may be reasonable to move from a commercial Unix to one of the BSD versions for applications, lower costs or support. And for anyone interested in the state of operating systems, it's worth knowing where BSD fits in.
I'm serving up something completely different this month, a popurri of technology items. There are items from a set of updated operating systems to Digital Libraries to a collection of earth images. Here is a brief list:
FreeBSD is the generalist OS of the BSD brigade. It can be used as server, router, workstation, and more than one of these at a time. While other BSD versions can do this, FreeBSD comes up the winner in the application arena. Nearly 7,000 applications will run natively on FreeBSD, some in precompiled packages, many by an automatic installation technology called 'Ports'.
The OpenBSD project produces a FREE, multi-platform 4.4BSD-based Unix-like operating system. OpenBSD's efforts emphasize portability, standardization, correctness, proactive security and integrated cryptography. OpenBSD supports binary emulation of most programs from SVR4 (Solaris), FreeBSD, Linux, BSD/OS, SunOS and HP-UX. OpenSSH is included in OpenBSD.
NetBSD is the most broadly available OS of the BSD group. On the main web page, they list no less than 33 processor architectures that are supported. Along with the supported systems, there is a separate page listing about a dozen more architectures currently being looked at or under development. It should be no surprise that with the 'Net' in NetBSD, networking is their forte. NetBSD has considerable support for IPv6, the next generation Internet standard. If you want to experiment on any network issue, grab a random bunch of hardware, install NetBSD and hack away.
With flexibility that FreeBSD gives, and full source code available, one can build a small installation performing various tasks, including (but not limited to):
From Apple's Developer site:
"Beneath the appealing, easy-to-use interface of Mac OS X is a rock-solid foundation that is engineered for stability, reliability, and performance. This foundation is a core operating system commonly known as Darwin. Darwin integrates a number of technologies, most importantly Mach 3.0, operating-system services based on 4.4BSD (Berkeley Software Distribution), high-performance networking facilities, and support for multiple integrated file systems."
One of the interesting things I observe about Mac OS X is its structure. By taking what some would say is the best implementation of each OS component, Mac OS X potentially has the strongest infrastructure in any personal OS currently available. With the strong Mach 3.0 as the kernel from Carnagie-Mellon University, the mature BSD OS components and the excellent user orientation of the Aqua interface from Apple, Mac OS X could become the benchmark for future personal computer operating systems.
See also this technical history of Darwin's development. Here is a quote from the Darwin history site:
"Darwin also incorporates a full implementation of BSD (Berkeley Software Distribution) UNIX, welded on top of the Mach kernel. The hybrid BSD architecture adopted by Darwin embodies its historical association with the BSD code base and underscores both the project's strong relationship with the various BSD organizations and its strong cultural affinity with the open source developer community. Indeed, Darwin itself constitutes a full-blown operating system, complete in and of itself, made available as open source by Apple -- a fact that's both astonishing and under-appreciated"
BSDi is the commercial BSD version, with professional support. If you want to run a critical company operation on BSD, getting the one with support is the most expensive up front, but cheaper than trying to find someone to fix the system while you're company is idle because of a problem or misconfiguration. As always, developing in-house resources may seem ideal, until that resource leaves for another job. Even if you do have local support, professional backup from BSDi is a great option to have.
4.4 BSD-LiteThe source code (45 MB) for the free parts of the original BSD. This is for those who want to look at the source, or want to roll their own for some special purpose. It is the base of the other BSD versions which were developed later.
Find a FreeBSD server near your location for faster access.
OpenBSD Security Alert Update to after Aug 11 to fix kernel attack.
(CSRG). : The 4CD set covers all BSD versions from 1BSD to 4.4BSD and 4.4BSD-Lite2 (but not 2.11BSD, unfortunately). As well, the last disk holds the final sources plus the SCCS files.
The second chapter of the book, The Design and Implementation of the 4.4BSD Operating System is excerpted here (at the linked site) with the permission of the publisher. Further publishing is prohibited, but you can read it there. Chapter 2 starts with an overview of the 4.4BSD system and can be a real source of understanding how BSD works. This could be a significant help to those non-gurus who want to extend their knowledge.
The Design and Implementation of the 4.4BSD
Operating System
by Marshall Kirk McKusick, Keith Bostic,
Michael J. Karels, John S. Quarterman
Copyright 1996 by Addison-Wesley Longman,
Inc
All content on this site is Copyright 2001 - 2004 by Bill Nicholls