When Sun Microsystems unveils today what it is touting as a radical advance in business computing, First Union Corp. will be in the vanguard of those adopting it. The announcement, at a media event in New York, will center on a hot trend that Sun reduces to three words: Java Enterprise Computing. Sun invited First Union, which has already deployed the technology in its capital markets operations, to share the spotlight with other Java innovators such as CSX, Federal Express, and British Telecom. Rarely has a bank company been so much a part of high-tech hype, which makes the First Union case and what it says about the potential impact of Java computing that much more noteworthy. Based on a programming language -- Java -- that came out of Sun Microsystems but is for practical purposes in the public domain, this new approach exemplifies what technologists call "network-centricity." It is widely seen as an antidote to the difficulty and expense of upgrading and maintaining vast numbers of personal computers in large organizations. First Union bought into the idea long ago and views Java computing as "a natural evolution," said Peter Kelly, senior vice president of the company's lead bank in Charlotte, N.C. After about five months of development and use, he reported "a dramatic reduction in both time and cost for training, administration, and maintenance." Participating in the announcement today, he said, First Union is less interested in glory or in endorsing Sun Microsystems -- the bank is drawn to Java because it is "vendor-neutral" -- than it is in "supporting a good business solution." In the network-centric model, processing and programming power reside away from the desktop on computers known as servers. Today's personal computers can be reduced to, or replaced by, less expensive "thin clients." These rely on "fat servers" for what analyst Jean S. Bozman of International Data Corp. calls "the heavy lifting." The computer press has recently given much attention to thin client opportunities in the home, such as an inexpensive appliance for Internet access that Oracle Corp., a leading advocate, dubbed the Network Computer, or NC. Sun's initial appeal is decidedly to the corporate community, where it believes revolutions happen first. "This may be the beginning of an incredible 10-year change in the way we do computing," Sun Microsystems Computer Co. president Edward J. Zander said in an interview last week. A thin client called JavaStation, along with an "easy administration" server, is to be included in Sun's announcement today. First Union is using the station to link a variety of desktop equipment with numerous data bases and files; Java breaks down the barriers between previously incompatible systems. Mr. Kelly said the bank would likely explore the technology's applicability outside of capital markets. Mr. Zander, who is based in Mountain View, Calif., said Java Enterprise Computing is especially and immediately applicable to "what we call fixed-function applications." These include many back-office and customer-service activities in financial services that can be managed and administered centrally and delivered through specialized thin-client screens. But what really attracts technologists' and business managers' attention is the economics. Sun projects 50% to 80% reductions in "the cost of ownership" of PCs, which can be tens or even hundreds of millions of dollars, depending on the size of a corporate network. Hype it may be, but it is hard to find anybody to argue against it. International Business Machines Corp., Microsoft Corp., Oracle Corp., and Netscape Communications Corp. -- technology leaders often at odds with one other and with Sun Microsystems -- have each jumped on this bandwagon in some way. (In other NC-related developments Monday, Oracle and Netscape announced a strategic alliance, as did an opposing group that included Microsoft, Intel Corp., and Hewlett-Packard Co.) Sun's ebullient Mr. Zander will talk a blue streak about almost anything on the leading edge, as he did last week in declaring, "Java computing is ready for prime time." But he was also careful not to oversell. Given the huge and entrenched population of PCs, he said, network computing is more evolutionary than revolutionary. Regarding Oracle chairman Lawrence Ellison's vision of $500 NCs' replacing virtually all PCs, Mr. Zander saw a lack of realism because PC-based spreadsheet and graphics applications, among others, are likely to persist. "We're not telling people to give up the power of the PC," Mr. Zander said, but to "put the complexity on the server, where it belongs . . . . It will take a couple of years, but it will happen." Mr. Kelly, who is responsible for First Union's capital markets technology and support, described JavaStation as a logical extension of the bank's work with object-oriented computing -- the programming approach that relies on reusable objects, or building-blocks of code -- and C++, the standard programming language from which Java was derived. Investment banking and capital markets gave Sun Microsystems its first major inroads into financial services, which may explain why Mr. Kelly's department has been looking into Java opportunities for more than a year. The stations have recently replaced "fat client" terminals in trade reconciliation, settlement, and clearing. "The redesign of an interface took only two to three weeks because we were already on the server-centric model," Mr. Kelly said. "This won't be the only client equipment we deploy . . . ," he added. "Interoperability is also our goal." The pricing does have a revolutionary ring to it. Sun said it would begin shipping the entry-level JavaStation in December, with miniSparc chip and eight megabytes of main memory, for $740. With keyboard, mouse, and 14-inch color monitor, it will go for $995; with double the memory and a 17-inch monitor, $1,495. A business PC installation rarely costs less than $3,000. And that is only part of what has come to irk corporate technology bosses. System maintenance, upgrades, and other expenses can amount to $12,000 per desktop per year. Java technology allows changes to be "written once and run anywhere" -- meaning "locally" on thin clients with powerful RISC (reduced instruction-set computing) processors embedded. A large corporation with JavaStations, which don't need hard or floppy or CD-ROM drives or moving parts because they depend on fat servers, "can save millions of dollars and deliver the same or better functionality, even if this is implemented by just 10% of your work force," said Gene Banman, general manager of Sun's desktop systems group. Sun executives expect JavaStation sales and related software applications to flourish -- they already count 450 of the latter -- because of the cost factor and the Internet and intranet boom. Java is "a secure universal interface language" designed specifically for broad distribution over such open networks without regard to hardware and operating-system choices, said Jeffrey P. Morgenthal, research analyst at D.H. Brown Associates, Port Chester, N.Y. Chief information officers can install Java "in phases without jeopardizing the existing infrastructure investment," he said. "I'm hard-pressed to believe that somebody is going to come up with an architecture in the near future to wipe this one out." Ms. Bozman, the International Data analyst in Mountain View, said alternative ways exist to shift the PC-support burden to central sites. But Java is gaining momentum. It burst on the Internet scene in the form of simple "applets" such as moving stock tickers but is evolving toward mission-critical corporate and packaged software. "This is not just happening in the Sun world," she said. "Even Microsoft is selling Java toolkits." Sun financial services vice president Rob Hall said he anticipates a rapid spread of Java computing because of the "dramatically lower total cost of ownership while providing flexible, platform-independent solutions. "We are seeing strong interest in our thin-client JavaStation for process-heavy and repetitive tasks such as trade settlement back-office operations and customer service applications in retail banking call centers," Mr. Hall said.