Microsoft has announced its upcoming Windows Longhorn server, due in 2007, will be closely allied to Intel's Itanium 64bit processor. Microsoft is promoting Longhorn and Itanium as an alternative to Unix and Risc processor systems, but Risc/Unix is a well-established platform for high- end systems, and currently looks stronger than ever.

For example, IBM's Power 5 Risc processor seems to be going from strength to strength. The Power 5 processor was designed primarily for high-end enterprise servers, but it has been adopted by Sony, Nintendo and Microsoft for their games consoles, and is also used in Apple Macs. In short, the Power 5 is now big business for IBM.

Of the major server makers, only HP seems committed to Itanium. But like its competitors, it seems more interested in the potential of AMD Opteron and Intel EM64T Xeon processors, which can run existing 32bit software as well as 64bit applications. These chips are more flexible for low-end, medium and even - in clustered form - high-end servers.

"Itanium will certainly be around in two years' time, but there is an ongoing debate as to whether it is the best choice," said Tony Lock, chief analyst at Bloor Research.

Mike Thompson of analyst company Butler Group concurred. "Microsoft has to look two years down the line to what high-end users will require," he commented.

Some question whether many companies will need new 64bit Itanium servers running Windows. If high-end Unix users make a move it may be towards Linux systems; and Opteron/EM64T systems are likely to handle most applications.

"The reliance on Itanium is a high-risk strategy," Thompson said. "Itanium coupled with Longhorn Server is a long way down the line. Is there a real need for this 64bit architecture? I feel it is a market slot that doesn't really exist. I think that the vast majority of Unix applications and users will go to Linux if they go anywhere. I cannot see why they would want to go to Microsoft."

Lock said Microsoft's announcement of support for Itanium puts down a marker suggesting it sees a future for Windows in high-end servers - a market currently dominated by Unix and Linux.

"There are signs that some software vendors are starting to think in terms of porting their applications to Risc platforms, and in particular to IBM's Power family of processors," Lock said.

Lock added that he hoped that Microsoft would decide to support other 64bit processors in future. "IBM's Power chip would be an obvious choice, though once that philosophical leap had been made, Sun's Sparc could also then become a possibility," he added.

But to create demand for Windows on 64bit hardware, more software vendors would have to develop business applications to exploit 64bit capabilities, said Lock.

"Companies don't buy servers because they want the box, but because there are applications that fit their business requirements, and all users would prefer to have choice." Even if Longhorn Server supports Itanium, there is no guarantee of a big market for it.