Buyers have varied choices for operating systems

Up to about 2000, that meant that the nuts and bolts of IT, such as file systems and disk utilities, became part of the operating system. Then operating systems became colorful, graphical and interoperable with a broad array of data sources. The Internet made multimedia and basic network support part of the standard feature set.

But today, security, reliability, ubiquitous communication and enterprise management are paramount concerns, a trend reflected in OSes. Built-in file encryption, Secure Sockets Layer security, IP networking and system administration are standard in server OSes.

A major focus of vendors for the past two to three years has been file-system technology. Schemes for managing files have been a core function of operating systems, but users now need to manage efficiently the terabytes of data that are growing thanks to the Web and the boom in high-capacity networked storage.

"It's not just a single, standalone type of technology and a part of the [OS] kernel, it's also the means to recover and to access data across a network," said George Weiss, vice president and analyst at market researchers Gartner Inc. of Stamford, Conn.

Newer file systems, such as the ZFS technology in the Unix-based Solaris OS from Sun Microsystems Inc., can simplify administration of disk volumes and file types, taking on some of the tasks of standalone storage-management software.

"The idea is to make it far simpler for the operating system to interoperate with that storage," said Bill Moffitt, Sun's group marketing manager for Solaris.

As always, hardware advances continue to drive OS capabilities. The driving advance today is the increasing affordability and performance of 64-bit CPUs ? and 64-bit extensions of existing 32-bit technology ? from Advanced Micro Devices Inc. of Sunnyvale, Calif., and Intel Corp.

Apple Computer Inc., Microsoft Corp. and Sun are all taking advantage of the orders-of-magnitude leap in memory capacities that 64 bits make possible. Scientific and other graphics-intensive, specialized workstation applications ? and some server apps ? remain the most common use for 64-bit systems.

But after a few years, as CPU prices come down, the technology will likely make its way into mainstream business and even multimedia home software.

Mostly because of the popularity of the Unix variant, Linux and the open source community that develops and shares the source code, today's OS choices are more varied ? and yet more alike ? than in the past.

Linux, especially the Red Hat distribution, is now common on Web servers and network edge applications such as firewalls, thanks in large part to IBM's major investment in the product.

Mandrakesoft and Suse Inc. also make Linux server software used at government agencies and corporations. Linux has struggled for acceptance on the desktop because of a dearth of off-the-shelf office applications: the open source OpenOffice, and its commercial version, Sun's StarOffice, remain the only major applications that truly compete with common Windows programs.

The security-conscious may opt for a specialized version, called Trusted Solaris, which meets security guarantees prescribed by the Common Criteria agreed to by dozens of governments worldwide.

Mark Thacker, Sun's product line manager for Trusted Solaris, said the Common Criteria address role-based access and security labeling and other mechanisms for segmenting and protecting data. Independent labs test products according to strict criteria and assign an Evaluation Assurance Level.

Meanwhile, Apple has been striving to expand use of its Macintosh platform beyond its core base of graphic designers, film editors and consumers. Apple said its next major release of the Mac OS, code-named Tiger and expected in the first half of 2005, will be fully 64-bit and have a new feature called Spotlight that lets you search drives by content rather than file names.

The PC OS underwent an evolution on the server side that led to the current version, Windows Server 2003, widely regarded as the first Windows OS with any pretense of competing with Unix in scalability and reliability, must-have capabilities on mission-critical systems.

Despite efforts by Red Hat and others to build a credible Linux client, Windows still reigns on the desktop. Microsoft lately is touting a major upgrade, code-named Longhorn, that will have a redesigned user interface that takes advantage of 3-D graphics hardware.

The desktop version of Longhorn is scheduled for public beta testing next year and has a ship date in 2006. A server version will follow six months later, according to Microsoft.

The OS world's new diversity within unity is apparent in the accompanying product listing, which includes only desktop and server operating systems, and omits specialized operating systems for handheld and tablet PCs, and embedded systems. n

David Essex is a free-lance technology writer in Antrim, N.H.