Virginia Polytechnic and State University was looking to build a supercomputer and do it without breaking the bank. It already had a small Advanced Micro Devices-based cluster running Linux, but eventually opted to deploy 1,100 of Apple's 64-bit Power Mac G5s early last year. In November, the university's Apple-based TeraScale cluster was ranked the third-fastest supercomputer in the world.The cluster has been offline for the past few months as the university replaces the Power Mac G5s with Xserve G5s, also based on the 64-bit PowerPC chip designed by IBM and Apple. Assembly has been completed, and final testing is underway. The system is expected to be in production soon, say engineers at Virginia Tech, in Blacksburg.The university expects a performance increase with the new hardware and also is expecting a boost from Apple's Unix-based server operating system, Mac OS X Server version 10.4, code-named Tiger.Expected to be released in the first half of next year, Tiger brings more than 200 new features, including native support for 64-bit applications, Ethernet link aggregation that binds Ethernet connections to enable failover and faster network performance, and access control lists that will let users go beyond traditional Unix permissions.Tiger comes after the October release of Mac OS X 10.3, code-named Panther, which has dozens of new capabilities and is aimed at simplifying integration between Macintoshes,\u00a0Windows\u00a0and\u00a0Linux environments.Apple has the same aspirations with Tiger, adding tools to simplify the migration of user and group account information from Windows Primary Domain Controller into Open Directory, for example. But it also includes a number of updates aimed at boosting performance and shoring up the operating system to support heavy-duty enterprise applications, such as databases and high-performance computing, says Tom Goguen, director of server software for Apple."Panther had partial 64-bit support, and Tiger will have full 64-bit support, which is going to affect high-performance computing quite a bit," says Josh Durham, a computer systems engineer at Virginia Tech. "Native support lets people write code that addresses the full amount of memory. Before we had around a 2G-byte per-process limit; now it's something enormous."Durham says 64-bit support coupled with updates in the Darwin kernel, which is the core of the BSD Unix-based operating system, will help boost performance. "All that should help speed up things quite a bit," he says.Analysts say that this latest release of Apple's server operating environment provides some useful technical updates. They note that the\u00a0Unix-based operating system is technically strong, comes with integrated open source applications that meet most business demands - such as the JBoss application server - and continues to ease deployment headaches with administrative tools. Xgrid, Apple's clustering software, for example, will be integrated into the Tiger operating system.\u00a0Eye on the TigerApple continues to push Mac OS as enterprise ready. A look at some of the key features that will come with the \u201cTiger\u201d operating system when it is released next year:\u2022Native support for 64-bit applications.\u2022Access Control Lists so that administrators can set more precise permissions for files and network services. \u2022iChat Server, to set up an internal, open source-based chat environment.\u2022Mobile Home Directories that store user files and preferences in a network server accessible from anywhere.\u2022Windows migration tools to make it easier to switch to a Mac OS environment.\u2022Integrated Xgrid software, making it easier to deploy computing clusters. "There are a lot of improvements, a lot of good things. And overall I look at [Tiger] and say technically it looks very good," says Dan Kusnetzky, program vice president of system software at IDC.At the same time, Kusnetzky notes that Apple is barely a blip in the operating system market, falling into the "other" category in a Unix segment that accounted for just 10.6% of overall server operating environments in 2003. Meanwhile, Windows held a 58% share, while paid shipments of Linux accounted for 23% of the worldwide market. Apple also is trying to compete in a 64-bit server market dominated by Sun, which has about 35% of the arena. IBM and HP are behind Sun, with about 12% market share, according to IDC."The key challenge isn't technical at this point, it's Apple creating a brand that businesspeople and IT decision makers are aware of, will consider and after considering will choose. It's more than rolling out a technically great product," Kusnetzky says.Michael Gartenberg, vice president and research director at Jupiter Research, agrees. He says that Apple provides an attractive alternative for corporations both on the desktop and on the server. Tiger includes more than 150 new features, highlighted by Spotlight, a search technology that lets users find anything on their hard drives - from files to e-mail to contact information to images - with a single tool.Pushing Apple to the top of a corporation's short list when it comes to server and client operating system remains the biggest challenge, he says."Tiger is clearly enterprise-ready," he says. "The challenge is getting folks in the IT department to overcome their Macintosh and Apple prejudices from days gone by."Pricing for the Tiger server will be the same as for Panther: just under $1,000 for unlimited users; a 10-client license costs $500. Subscribers to the Apple Maintenance Program will get the updated operating system as part of their maintenance service. The suggested retail price for the Tiger client operating system is $130.