FreeBSD
Berkeley Software Distribution (BSD, sometimes called Berkeley Unix) is the Unix derivative distributed by the University of California, Berkeley, starting in the 1970s. The name is also used collectively for the modern descendants of these distributions. BSD is one of the two branches of the Unix operating systems. The other one is evoled from UNIX System V develpped by AT&T Bell lab.
BSD was widely identified with the versions of Unix available for workstation-class systems. This can be attributed to the ease with which it could be licensed and the familiarity it found among the founders of many technology companies during the 1980s. This familarity often came from using similar systems—notably DEC's Ultrix and Sun's SunOS—during their education. While BSD itself was largely superseded by the System V Release 4 and OSF/1 systems in the 1990s (both of which incorporated BSD code), in recent years modified open source versions of the codebase (mostly derived from 4.4BSD-Lite) have seen increasing use and development.
Other universities became interested in the software at Berkeley, and so in 1977 Bill Joy, then a graduate student at Berkeley, assembled and sent out tapes of the first Berkeley Software Distribution (1BSD). 1BSD was an add-on to Sixth Edition Unix rather than a complete operating system in its own right; its main components were a Pascal compiler and Joy's ex line editor.
The Second Berkeley Software Distribution (2BSD), released in 1978, included updated versions of the 1BSD software as well as two new programs by Joy that persist on Unix systems to this day: the vi text editor (a visual version of ex) and the C shell.
A VAX computer was installed at Berkeley in 1978, but the port of Unix to the VAX architecture, UNIX/32V, did not take advantage of the VAX's virtual memory capabilities. The kernel of 32V was largely rewritten by Berkeley students to include a virtual memory implementation, and a complete operating system including the new kernel, ports of the 2BSD utilities to the VAX, and the utilities from 32V was released as 3BSD at the end of 1979. 3BSD was also alternatively called Virtual VAX/UNIX or VMUNIX (for Virtual Memory Unix), and BSD kernel images were normally called /vmunix until 4.4BSD.
The success of 3BSD was a major factor in the Defense Advanced Research Projects Agency's (DARPA) decision to fund Berkeley's Computer Systems Research Group (CSRG), which would develop a standard Unix platform for future DARPA research in the VLSI Project. CSRG released 4BSD, containing numerous improvements to the 3BSD system, in October 1980.
4.1BSD (June 1981) was a response to criticisms of BSD's performance relative to the dominant VAX operating system, VMS. The 4.1BSD kernel was systematically tuned up by Bill Joy until it could perform as well as VMS on several benchmarks. (The release would have been called 5BSD, but the name was changed to avoid confusion with AT&T's UNIX System V release. One early, never-released test version was in fact called 4.5BSD.)
4.2BSD would take over two years to implement and contained several major overhauls. Before its official release came three intermediate versions: 4.1a incorporated a modified version of BBN's preliminary TCP/IP implementation; 4.1b included the new Berkeley Fast File System, implemented by Marshall Kirk McKusick; and 4.1c was an interim release during the last few months of 4.2BSD's development.
The official 4.2BSD release came in August 1983. It was notable as the first version released after the 1982 departure of Bill Joy to co-found Sun Microsystems; Mike Karels and Marshall Kirk McKusick took on leadership roles within the project from that point forward. On a lighter note, it also marked the debut of BSD's daemon mascot in a drawing by McKusick that appeared on the cover of the printed manuals distributed by USENIX.
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4.3BSD was released in June 1986. Its main changes were to improve the performance of many of the new contributions of 4.2BSD that had not been as heavily tuned as the 4.1BSD code. Prior to the release, BSD's implementation of TCP/IP had diverged considerably from BBN's official implementation. After several months of testing, DARPA determined that the 4.2BSD version was superior and would remain in 4.3BSD.
FOR MORE INFORMATION ,DETAILS AND RESOURCES ON BSD
BSD was widely identified with the versions of Unix available for workstation-class systems. This can be attributed to the ease with which it could be licensed and the familiarity it found among the founders of many technology companies during the 1980s. This familarity often came from using similar systems—notably DEC's Ultrix and Sun's SunOS—during their education. While BSD itself was largely superseded by the System V Release 4 and OSF/1 systems in the 1990s (both of which incorporated BSD code), in recent years modified open source versions of the codebase (mostly derived from 4.4BSD-Lite) have seen increasing use and development.
Other universities became interested in the software at Berkeley, and so in 1977 Bill Joy, then a graduate student at Berkeley, assembled and sent out tapes of the first Berkeley Software Distribution (1BSD). 1BSD was an add-on to Sixth Edition Unix rather than a complete operating system in its own right; its main components were a Pascal compiler and Joy's ex line editor.
The Second Berkeley Software Distribution (2BSD), released in 1978, included updated versions of the 1BSD software as well as two new programs by Joy that persist on Unix systems to this day: the vi text editor (a visual version of ex) and the C shell.
A VAX computer was installed at Berkeley in 1978, but the port of Unix to the VAX architecture, UNIX/32V, did not take advantage of the VAX's virtual memory capabilities. The kernel of 32V was largely rewritten by Berkeley students to include a virtual memory implementation, and a complete operating system including the new kernel, ports of the 2BSD utilities to the VAX, and the utilities from 32V was released as 3BSD at the end of 1979. 3BSD was also alternatively called Virtual VAX/UNIX or VMUNIX (for Virtual Memory Unix), and BSD kernel images were normally called /vmunix until 4.4BSD.
The success of 3BSD was a major factor in the Defense Advanced Research Projects Agency's (DARPA) decision to fund Berkeley's Computer Systems Research Group (CSRG), which would develop a standard Unix platform for future DARPA research in the VLSI Project. CSRG released 4BSD, containing numerous improvements to the 3BSD system, in October 1980.
4.1BSD (June 1981) was a response to criticisms of BSD's performance relative to the dominant VAX operating system, VMS. The 4.1BSD kernel was systematically tuned up by Bill Joy until it could perform as well as VMS on several benchmarks. (The release would have been called 5BSD, but the name was changed to avoid confusion with AT&T's UNIX System V release. One early, never-released test version was in fact called 4.5BSD.)
4.2BSD would take over two years to implement and contained several major overhauls. Before its official release came three intermediate versions: 4.1a incorporated a modified version of BBN's preliminary TCP/IP implementation; 4.1b included the new Berkeley Fast File System, implemented by Marshall Kirk McKusick; and 4.1c was an interim release during the last few months of 4.2BSD's development.
The official 4.2BSD release came in August 1983. It was notable as the first version released after the 1982 departure of Bill Joy to co-found Sun Microsystems; Mike Karels and Marshall Kirk McKusick took on leadership roles within the project from that point forward. On a lighter note, it also marked the debut of BSD's daemon mascot in a drawing by McKusick that appeared on the cover of the printed manuals distributed by USENIX.
[edit]
4.3BSD was released in June 1986. Its main changes were to improve the performance of many of the new contributions of 4.2BSD that had not been as heavily tuned as the 4.1BSD code. Prior to the release, BSD's implementation of TCP/IP had diverged considerably from BBN's official implementation. After several months of testing, DARPA determined that the 4.2BSD version was superior and would remain in 4.3BSD.
FOR MORE INFORMATION ,DETAILS AND RESOURCES ON BSD