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Executive Summary

Is it possible for an Information Technology [IT] product to be both mature and state-of-the-art at the same time? In the case of the UNIX® system, the answer is an unqualified "Yes." The UNIX system has continued to develop over the past twenty-five years. In millions of installations running on nearly every hardware platform made, the UNIX system has earned its reputation for stability and scalability. Over the years, UNIX system suppliers have steadily assimilated new technologies so that UNIX systems today provide more functionality as any other operating system.

Perhaps the key to the continuing growth of the UNIX system is the free-market demands placed upon suppliers who produce and support software built to open standards. The "open systems" approach is in bold contrast to other operating environments that lock in their customers with resultant high switching costs. UNIX system suppliers, on the other hand, must constantly provide the highest quality systems in order to retain their customers. Those who become dissatisfied with one UNIX system implementation retain the ability to easily move to another UNIX system implementation.

The continuing success of the UNIX system should come as no surprise. No other operating environment enjoys the support of every major system supplier. Mention the UNIX system and IT professionals immediately think not only of the operating system itself, but also of the large family of application software that the UNIX system supports. In the IT marketplace, the UNIX system has been the catalyst for sweeping changes that have empowered consumers to seek the best-of-breed without the arbitrary constraints imposed by proprietary environments.

In a nutshell then, the UNIX system is the users' and suppliers' operating environment of choice. The UNIX system represents the best collective efforts of competing suppliers, the most refined standards in the public domain, and the rock-solid stability that comes from years of quality assurance testing, mission-critical use, and refinement.

This white paper examines the UNIX system with a special concern for both its extraordinary past and its equally extraordinary prospects for the future.

The UNIX System

The UNIX system has been around for a long time, and many people may remember it as it existed in the previous decades. Many IT professionals who encountered UNIX systems in the past found it uncompromising. While its power was impressive, its command-line interface required technical competence, its syntax was not intuitive, and its interface was unfriendly.

Moreover, in the UNIX system's early days, security was virtually nonexistent. Subsequently, the UNIX system became the first operating system to suffer attacks mounted over the nascent Internet. As the UNIX system matured, however, the organization of security shifted from centralized to distributed authentication and authorization systems.

Today, these perceptions are only of historical interest.

Now, a single Graphical User Interface is shipped and supported by all major vendors has replaced command-line syntax, and security systems, up to and including B1, provide appropriate controls over access to the UNIX system.

The Value of Standards

The UNIX system's increasing popularity spawned the development of a number of variations of the UNIX operating system in the 1980s, and the existence of these caused a mid-life crisis. Standardization had progressed slowly and methodically in domains such as telecommunications and third-generation languages; yet no one had addressed standards at the operating system level. For suppliers, the thought of a uniform operating environment was disconcerting. Consumer lock-in was woven tightly into the fabric of the industry. Individual consumers, particularly those with UNIX system experience, envisioned standardized environments, but had no way to pull the market in their direction.

However, for one category of consumer -governments- the standardization of the UNIX system was both desirable and within reach. Governments have clout and are the largest consumers of information technology products and services in the world. Driven by the need to improve commonality, both US and European governments endorsed a shift to the UNIX system. The Institute of Electrical and Electronic Engineers POSIX family of standards, along with standards from ISO, ANSI and others, led the way. Consortia such as the X/Open Company (merged with the Open Software Foundation in 1995 to form The Open Group) hammered out draft standards to accelerate the process.

In 1994, the definitive specification of what constitutes a UNIX system was finalized through X/Open Company's consensus process. The Single UNIX Specification was born-not from a theoretical, ivory tower approach, but by analyzing the applications that were in use in businesses across the world.

With the active support of government and commercial buyers alike, vendors began to converge on products that implement the Single UNIX Specification, and now all major vendors have products labeled UNIX 95, which indicates that the vendor guarantees that the product conforms to the Single UNIX Specification.

Vendors continue to add value to the UNIX system, particularly in areas of new technology, however that value will always be built upon a single, consensus standard. Meanwhile, the functionality of the UNIX system was established and the mid-life crisis was resolved. Suppliers today provide UNIX systems that are built upon a single, consensus standard.

It is also important to remember that even when variance among UNIX systems was at its worst, IT professionals agreed that migration among UNIX system variants was far easier than migration among the proprietary alternatives.

Now with UNIX 95 branded products available from all major systems vendors, the buyer can for the first time buy systems from different manufacturers, safe in the knowledge that each one is guaranteed to implement the complete functionality of the Single UNIX Specification and will continue to do so.

UNIX system suppliers can assure customers that they own a standards-based system by registering them to use the Open Brand. Below is a list of suppliers who give users this guarantee.
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