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It isn't licensed to other vendors nor are its specifications determined by vendors outside of Apple. In sharp contrast, the TCP/IP protocol suite is both openly specified in extensive documents (RFCs) and influenced by a large population of users.

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<P>Software that is built to open standards, whether through open specifications or open licensing, promotes interoperability. Consider the example of the role that Sun Microsystems has had in promoting open systems. The published specifications for its 
network file system (NFS) have allowed it to be incorporated or otherwise made available in most every UNIX operating system and as an add-on utility for personal systems such as PCs and Macintosh systems. NFS was designed to provide distributed file 
systems between computers from different manufacturers running different operating systems. Sun, more than any computer corporation, has used the standards process both to its own strategic advantage and to promote open systems.

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<H3 ALIGN="CENTER">

<CENTER><A ID="I14" NAME="I14">

<FONT SIZE=4><B>The Role of Standards and Consortiums</B>

<BR></FONT></A></CENTER></H3>

<P>Slowly, the evolution of standards has begun to ease the work of UNIX developers and end users. Users of heterogeneous networks with computers from many different vendors are finding ways to share information effectively. Software products are finding 
easier ports to new platforms. Standards are also becoming big business as the specification of compliance with the emerging set of important standards is increasingly included in large contracts. If a federal procurement requires POSIX compliance, large 
vendors will scramble to make their offerings POSIX compliant. Standards affect the way that a UNIX system acts both on the outside (for example, the syntax of user commands) and on the inside (for example, how it does system calls).

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<P>Standards are important to end users because following standards leads to software becoming cheaper to produce, with a resultant drop in price and increase in availability. In the past, it may have cost ten times as much to buy a software product for 
most UNIX platforms simply because the ratio of development cost to customer base was too large. With effective standards, software can be ported at considerably less cost, resulting in a higher availability of inexpensive software for all UNIX systems.

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<P>Both SVR4 and OSF/1 include specification of an application binary interface (ABI), which allows compiled code to be run on diverse hosts if they can run the ABI interface software. The ABI promises shrink-wrapped software that says just 
&quot;UNIX&quot; on the box; this is certainly an ideal. The idea is not entirely new. The Pascal language included a very similar concept with its use of p-code. Pascal compiles to the intermediate p-code, which can then be compiled or interpreted by a 
small piece of machine-specific software. Software that runs using an ABI will take advantage of a similar technique.

<BR></P>

<P>UNIX vendors are not the only ones interested in standards. System administrators are interested in standards that facilitate management of large collections of often diverse systems. Administrators often have the superset of problems that face 
developers, end users, and system integrators. Standards of interest to systems administrators include distributed management of resources. Standards for network management, distributed systems administration, and distributed computing are high on their 
lists. Programmers, on the other hand, want standard interfaces to facilitate program development and standard development tools.

<BR></P>

<P>Indeed, the move toward a uniform UNIX has created some strange bedfellows. Alliances between previously bitter rivals have become commonplace as the drive to define a unified UNIX and the drive to maintain market leadership force UNIX vendors to take 
strange turns. The major UNIX vendors are all participating in efforts to end the UNIX feuds.

<BR></P>

<P>Some of the most important standards that apply to UNIX are described briefly in the following sections.

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<H4 ALIGN="CENTER">

<CENTER><A ID="I15" NAME="I15">

<FONT SIZE=3><B>SVID</B>

<BR></FONT></A></CENTER></H4>

<P>SVID, the System V Interface Definition and Verification Suite, has increasingly more clout as large backers, including the federal government, look to standards to protect their investment in computer technology and ease the work of managing huge 
information processing operations. SVID standards also include conformance testing. The System V Verification Suite is used to gauge adherence to SVID. SVR4 is, as you might have guessed, SVID-compliant.

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<H4 ALIGN="CENTER">

<CENTER><A ID="I16" NAME="I16">

<FONT SIZE=3><B>POSIX</B>

<BR></FONT></A></CENTER></H4>

<P>POSIX, a standard started by /usr/group, an organization made up of UNIX System users, and eventually IEEE-supported, sets a standard for a portable operating system interface for computer environments. POSIX defines the way applications interact with 
the operating system. It defines, for example, system calls, libraries, tools, and security.

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<H4 ALIGN="CENTER">

<CENTER><A ID="I17" NAME="I17">

<FONT SIZE=3><B>X/Open</B>

<BR></FONT></A></CENTER></H4>

<P>X/Open is a consortium that was started by European companies. X/Open publishes guidelines for compatibility leading to portability and interoperability. The X/Open portability guide was first published in 1985. At one time, both OSF and UI were 
members, but OSF has left the group. X/Open has a series of groups in areas such as the UNIX kernel, distributed processing, and security.

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<H4 ALIGN="CENTER">

<CENTER><A ID="I18" NAME="I18">

<FONT SIZE=3><B>COSE/CDE</B>

<BR></FONT></A></CENTER></H4>

<P>Another vendor-driven alliance, the Common Open Software Environment (COSE)&#151;with partners IBM, HP, SunSoft, UNIX System Laboratories, Univel, and the Santa Cruz Operation&#151;formed to work on a common graphical interface for UNIX based on 
OSF/Motif. Sun's involvement in this coalition and its adoption of Motif ended a longtime standoff in the UNIX GUI battleground. A large part of what this group is defining is called the Common Desktop Environment (CDE).

<BR></P>

<P>The COSE efforts are bringing a unified look-and-feel and behavior model to the UNIX desktop. UNIX has always lacked a unified model even though the desktops of many popular versions of UNIX have been easy to use. To the extent that this effort is 
successful, the skills of UNIX end users can carry over from one UNIX system to the next.

<BR></P>

<P>CDE itself is based on a long list of standards that the UNIX community has been using and relying on for some time. These standards include the X11R5 windowing environment, the OSF/Motif GUI, and the ICCCM standard for interclient communications. COSE 

will also develop a style guide for CDE.

<BR></P>

<P>SunSoft's desktop tools, including a calendar manager, file manager, and mail tool, and SunSoft's ToolTalk for messaging between applications are also being incorporated into the CDE. HP's Visual User Environment and the windowing Korn shell will also 
be incorporated.

<BR></P>

<H3 ALIGN="CENTER">

<CENTER><A ID="I19" NAME="I19">

<FONT SIZE=4><B>War and Peace</B>

<BR></FONT></A></CENTER></H3>

<P>The stage was finally set for the development of a unified UNIX when, in 1988, AT&amp;T purchased a percentage of Sun. Immediately following the fairly startling announcement of this purchase, a group of vendors, including IBM, DEC, and HP, set out to 
compete with the SVR4 direction that Sun and AT&amp;T were taking. Calling themselves the Open Software Foundation (OSF), they were clearly reacting against the evidence of impending collaboration between Sun and AT&amp;T that would unify UNIX and possibly 

give them a competitive advantage in marketing their products. OSF quickly raised $90 million for the development of their own standard, intent on avoiding licensing fees and possible &quot;control&quot; of UNIX by competitors.

<BR></P>

<P>AT&amp;T and Sun Microsystems then reacted to the formation of OSF by establishing UNIX International, a set of System V endorsers that would be responsible for its future specifications. This consortium would oversee the development of the standard 
UNIX. Sun and AT&amp;T hoped to ward off complications that would result from the establishment of yet another standard for UNIX. This move, apparently, did not appease the founders of OSF, and both organizations continued their efforts to bring about 
their own answer to the need for a unified UNIX.

<BR></P>

<P>OSF developed the Motif GUI and the OSF/1 version of UNIX. OSF/1 is based on the Mach system, which is, in turn, based on UNIX System V Release 3.

<BR></P>

<P>Although the ultimate success of OSF/1 was still in question, the division of UNIX into another pair of competing technologies threatened the unification of UNIX envisioned by the Sun/AT&amp;T establishment of SVR4.

<BR></P>

<P>For years, these vendor groups were at odds. Sun swore that it would never endorse OSF's Motif GUI standard, and OSF steadfastly pursued development of its own technology, charging fees for licensing Motif. In March 1993, however, Sun adopted Motif as a 

windowing direction, promising to end the &quot;GUI Wars,&quot; which complicated the lives of UNIX users looking for products that complied with Motif or Sun's Open Look, depending on their preferences, or living with a mixed-GUI desktop that sometimes 
made moving from one tool to another difficult.

<BR></P>

<P>When OSF reorganized in March 1994, however, it revised its charter to focus closely on specifications of vendor-neutral standards, rather than creating licensable technology. This change left participating vendors able to use these specifications to 
develop their own implementations (which they then own and don't have to license) and brings greater adherence to OSF's standards to most of the UNIX community.

<BR></P>

<H3 ALIGN="CENTER">

<CENTER><A ID="I20" NAME="I20">

<FONT SIZE=4><B>The UNIX Future</B>

<BR></FONT></A></CENTER></H3>

<P>UNIX is, in most ways, stronger than ever. The alliances that have formed to bring about a uniformity will dramatically simplify portability of applications and allow end users to develop transferable skills on most UNIX desktops.

<BR></P>

<P>UNIX rarely comes with source code anymore, and one effect of compliance with a myriad of standards is to slow innovation. You will never have UNIX quite the way it was in its formative years&#151;small and pliable. Those times are lost, a necessary 
cost of UNIX's amazing success. Today, the UNIX system is not quite so simple as it was back then. When networking was added, followed by Windows and GUI support, UNIX became increasingly complicated. The exception, however, is the continued availability 
of the Berkeley version of UNIX through Berkeley Systems Design, Inc. Available with and without source code, BSDI's UNIX product runs on Intel systems.

<BR></P>

<P>At the same time, UNIX continues to provide stunning new capabilities. Real-time features, multi-threaded kernels, virtual file systems, and user desktops that provide intuitive access to the system not only to end users but to system administrators are 

only examples.

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<P>The strong appeal of interoperability is increasingly important as large companies and government agencies plan how they will tie their resources together in enterprise networks in what is left of the 1990s. End users want portability because it saves 
them money. Developers want it to reduce their workload and lower their costs. Big customers want to leverage their investments. You are likely to see many organizations running UNIX across the enterprise and many others with UNIX on servers and 
workstations and other operating systems on personal computers.

<BR></P>

<P>UNIX is becoming less and less a system that only wizards and programmers use and more a system that everyone&#151;including businesspeople&#151;use. UNIX has not sacrificed, however, any of its elegance but acquired a veneer that appeals to less 
system-savvy users. Users today want services transparently and, for the most part, don't really want to use computers so much as to get some job done. They are not the same people who made UNIX popular in the early days. UNIX has made it into big business 

and into big finance and sits on the desktop of CEOs and secretaries, not just programmers and engineers. These users want GUIs, desktop tools, and transparent access to remote and disparate systems without having to be conscious of the differences between 

their platforms.

<BR></P>

<P>The development of a common desktop will allow users to move easily from one UNIX system to another without &quot;retraining their fingers.&quot; Until a true binary standard (ABI) appears, you will still be driven, in part, by applications that may be 

available on one platform and not another. Just as many personal computers were once sold because users wanted to use the Lotus spreadsheet, systems still sometimes sell on the strength of powerful or customer-specific software&#151;such as Wolfram's 
Mathematica&#151;that may not be available on every UNIX platform.

<BR></P>

<P>Another similar trend is the appearance of system-management tools that provide uniform management of diverse systems to even the most heterogeneous networks. Hiding the platform-specific details from the user relieves the systems administrator from 
having to be an expert on every different system on the network.

<BR></P>

<P>When you really get down to it, the differences between flavors of UNIX are not really all that great, given adherence to the current set of standards. Almost any current operating system with any relation to UNIX will conform to the standards such as 
SVID and POSIX and the X/Open guidelines. The cohesiveness of heterogeneous networks and the common desktop environment for UNIX systems are likely to be the factors that most heavily influence the future success of UNIX. At the same time, companies will 
be motivated to differentiate their versions of UNIX in spite of their support to the goals of a unified UNIX in order to sell their product.

<BR></P>

<P>The war is no longer UNIX vs. UNIX, even though battles will still be fought between vendors competing for your purchases with whatever added value they can bring to their products without violating the alliances they have joined to support the unified 

UNIX. The war will be between open and proprietary, between standards-backed UNIX and contenders such as Windows NT vying for the desktop in the enterprise network. If the open systems movement is to continue to bring value to the working lives of 
programmers, systems administrators, and end users of UNIX systems, they must continue to insist on adherence to open standards and the &quot;plug and play&quot; desktop.

<BR></P>

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