Datacenter Edition is only available preinstalled on a server from approved OEMs: Fujitsu Siemens, Hewlett-Packard, IBM and Unisys for the 32-bit version; H-P, IBM, NEC and Unisys for the 64-bit.
It supports 8-, 16- and 32-way SMP, but not 2- or 4-way, and a maximum of 64GB RAM (32-bit) or 512GB (64-bit). Since it is not designed for edge applications, it does not include a firewall, network bridge or ICS.
Mounting the Siege
While part of Microsoft's motivation for offering an expanded product line may simply be a desire to better serve its existing customers, it also means that it can expand into markets where other operating systems have a stronghold.
At the upper end, its Enterprise and Datacenter versions lay siege to the mission critical servers currently running Unix. To further expand Windows into this area, Microsoft is giving away Windows Services for Unix 3.0, which lets Unix applications run under Windows. It is also creating online training courses to teach Unix developers and administrators the basics of Windows.
On the lower end its Web Edition challenges Linux's domination of that arena. But will it actually eat into either Linux's or Unix's market share, or will existing Windows users simply migrate to it from Windows NT/2000?
"The Web Edition helps Microsoft be more competitive with Linux at the low end," says Tom Bittman, research vice president for Gartner, Inc., based in Stamford, Conn.
But Bittman doesn't feel it is attractive enough to get Linux users to make the switch. Instead he says that most of the Windows Server 2003 sales will come from people replacing their existing hardware running Windows NT 4.0.
"It is a good release with lots of useful enhancements, but it is an incremental release except for Active Directory and IAS," he explains. "Therefore, companies are not going to see an ROI by upgrading to that release outside of their normal hardware refresh cycle."