Windows server revenues reached $17.7 billion for all of 2005, barely edging out Unix's server revenues of $17.5 billion for the year, according to IDC's Worldwide Server Tracker. The report said that this was the first time in over a decade that Unix did not lead the market in year-end server revenue.
These latest numbers from IDC and similar findings from Gartner are not surprising to industry watchers, many of whom credit Microsoft's security initiatives over the past several years as one of the factors leading to improved Windows server sales.
"Security is an ongoing battle," said Laura DiDio, a research fellow for Yankee Group. "Microsoft can never declare victory. But clearly, Microsoft has made great strides hardening the OS."
DiDio pointed to recent Yankee Group user surveys to illustrate these improvements made by Microsoft. User confidence in Windows server security doubled between 2004 and 2005, according to surveys conducted by the firm.
"I think that is clear and tangible evidence and proof that the trustworthy security initiatives, as well as the hardening of the OS and the new patch management schedule that they have implemented are making a difference," Didio said.
In spite of these improvements, some wonder how much more room Microsoft has to grow in the server market. Windows has primarily caught fire in the SMB markets, while making hopeful advances toward larger enterprises with complex data-center needs. Microsoft may face problems in this arena given their reputation for ignoring security problems in the past, said Pund-IT analyst Charles King.
"The question does come up that if I'm a business and I'm used to the high-level security that is common in Unix, does Microsoft's relatively spotty record with security issues scare me away," King said. "And is that going to create some kind glass ceiling above which Microsoft cannot proceed?"
DiDio does not believe there is a glass ceiling for Microsoft in terms of server growth, simply because the overall market continues to grow.
"The pie itself is not finite," she said, arguing that emerging markets around the globe could contribute to further growth.
As Microsoft continues to strengthen its grasp on the server market, DiDio said that all businesses must remain aware of the effect that Windows server ubiquity will have on their security.
"The larger the install base, the greater the concern about security, because there are all of these interdependencies," she said.
Even those that choose a different alternative must watch their step, she warned, as they are more likely to be affected by others' Windows server problems.
"Even if you've got a homogenous Linux or Unix server environment, at some point you are going to have a business partner, a customer or a supplier that is using Windows and is going to touch your network," DiDio said. "And if you haven't secured those environments, then that could be a backdoor for a worm or a virus to infect your Windows network."