McKusick, Marshall Kirk

Organizational History

AT&T's Bell Labs began development on the UNIX operating system in 1969. In 1973 an early release was distributed free-of-charge to a number of educational and research institutions, including UC Berkeley. Berkeley Software Distribution (BSD) began as a UNIX derivative, created by researchers and students at the University of California, Berkeley, as supplements to the UNIX operating system developed at AT&T's Bell Labs.

Between 1977-1980, UC Berkeley released four software distributions. While the first two releases (known as 1BSD and 2BSD) contained mostly additions to AT&T's UNIX architecture, the next release, 3BSD was a full-fledged operating system, although it still depended heavily on AT&T's proprietary UNIX source code.

In 1980, based on the success of the 3BSD operating system, the Defense Advanced Research Projects Agency (DARPA) agreed to provide UC Berkeley with funding to development a standard UNIX platform for future DARPA research. The Computer Systems Research Group (CSRG) was formed to lend greater organization to the existing effort. From 1980-1992, a number of major software distributions were released by the CSRG, including 4BSD, 4.1BSD, and 4.2BSD, as well as Net/1 and Net/2.

Over time, less and less of the operating system depended upon the original AT&T source code. By the release of Net/2 in 1991, CSRG developers believed that it was no longer necessary for users of their operating system to also buy UNIX licenses from AT&T, which had been a requirement in earlier releases. AT&T disagreed, and in 1992 (the same year BSD was ported to the Intel 80386 architecture) they sued BSDi, a corporation founded by several former members of CSRG which had distributed, sold licenses to, and provided commercially support for a version of the BSD operating system. AT&T claimed BSDi's distribution included proprietary code and trade secrets. Soon after, AT&T filed a second suit, against the University of California. Following Novell's purchase of the AT&T subsidized laboratory that specialized in UNIX in 1993, the suit was settled in 1994. As part of the settlement, two forms of 4.4BSD were released in June of that year: the freely distributable 4.4BSD-Lite containing no AT&T source code, and 4.4BSD-Encumbered, available only to those who had purchased AT&T licenses.

In 1995, following the release of 4.4BSD-Lite Release 2, the Computer Systems Research Group was dissolved, ending development of BSD at UC Berkeley. Although official university development halted in 1995, a number of unaffiliated user groups around the world continued to develop BSD code under a variety of projects, including FreeBSD, NetBSD, and OpenBSD.

Chronology