* Microsoft NT
* Solaris 8
* In the early 1990s, UNIX-based workstations comprised 85-90% of the workstation market. * In the year of 98, NT workstations outshipped UNIX-based machines by more than 1 million units, -> but UNIX still accounted for 54% of workstation market revenue. * OS market shares in 99
* MS OS ran on 90%
* Apple on 4%
* Amiga and others
OS was in incompetible, => an app written for one OS could not run on another. UNIX were developed by AT&T, but licensed any interested party for a minimal fee => several different branches were developed -> FX the BSD version (Berkeley Software Distribution). Many of the hardware suppliers made their own version of UNIX whit competing features. (IBM, Hewlett-Packard, and Sun) => different workstation and server manufacturers’ UNIX-based systems diverged in several characteristics.
* servers = the backbone of networks (where printers , files and applications software are share) * “client-server” architecture.
* servers could do many different task .> from serving files to users to more complex ERP functions. * servers relied on multiple microprocessors => more reliable and scalable than a PC or workstation. The GNU project => The GNU public license, or GPL (nicknamed “copyleft”): * In 1984, Richard Stallman left his job at MIT’s -> to develop a reely available, UNIX-like operating system: the GNU Project * Stallman was frustrated in that he was not allow to improve source code of the program in his lap * Stallmen was concerned with the rise of proprietary software threatened the ability of programmers to share ideas and advance programming according to the norms of open science. * He was concerned that private sector firms might make proprietary modified versions of GNU software, -> defeating the purpose of his efforts, Stallman designed a new license for the software’s distribution. The GNU public license, or GPL (nicknamed “copyleft”), allowed free use of a program’s source code but required that any modifications be similarly made publicly available under the GPL. * Users could access to the source code, understand how a program worked, and could make changes to that program if desired. * By 1990, the GNU Project developed -> command processors, assemblers, compilers, and text editors. -> These programs became widely popular because they were compatible with UNIX LINUX:
* In 1991, Linus Torvalds wrote his own UNIX-like kernel to run on his Intel 386 chip-based PC. * Torvalds publiced the code under the GPL, -> and shortly thereafter began to receive emails from users containing “patches” * In 1992 -> Torvalds completed the GNU/Linux operating system. * Linux was free but complex to install => users were willing to pay for the convenience of getting them all on a CD. => distributors emerged and began to ship their own branded versions of Linux, enhancing it with programs written by their own developers. * By 1998, the Linux kernel had grown to more than 1.5 million lines of code, less than 5% of which was written by Torvalds himself * In 1998, Corel and Oracle, announced that they would “port” their software to Linux. * In 1999, HP, SGI and IBM all announced that they would support Linux on their hardware platforms * By the end 99, more than 100 Linux distributions were produced by a wide range of for-profit and non-profit organizations * Red Hat became the first Linux distribution firm to go public Customers:
* were often compagnies
* As the complexity of a server’s tasks increased, and as the tasks involved became more “mission-critical” for an organization, issues of reliability and customer support rose in prominence. * as the number of users increased, customers were more likely to consider issues of reliability and “scalability” Independent...