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Of course, this is also a key feature of Windows Server 2003. Microsoft is simply signaling that “Longhorn” will continue its roadmap of providing role-fittable Windows versions. This is not a change of direction for Microsoft, by any means. Even within the principal editions of Windows Server 2003, Microsoft encourages enterprises to regard their deployments of the product in a quasi-commodity, role-oriented fashion. Specifically, administrators use a “Manage Your Server” wizard to define the specific server roles that a particular Windows Server 2003 deployment will address, such as domain controller, file server, Web server, and application server. For example, if a Windows Server 2003 deployment is set up solely as a stand-alone departmental file server, the wizard will prevent IIS 6.0, and all of its associated Web and Internet protocol interfaces, from being installed on that server.
Microsoft’s “role-fitted Windows” approach is evidence of ongoing commoditization in the server OS and application platform markets. Commoditization of the server market—not Linux or the open-source community—is Microsoft’s biggest foe and poses the most fundamental threat to the long-term profitability and revenue growth of traditional software vendors. Commodity-like offerings, many of them based on open-source software, are starting to come on strong in many market niches, such as Web servers (Apache, for example) and mail servers (Sendmail, for example).
Microsoft’s response to the server commoditization challenge is savvy. In any market, companies compete on product price or features (or both), and Steve Ballmer has clearly stated that Microsoft will step up R&D in order to distinguish its offerings from rival software products in the various niches where it competes. Microsoft is also increasingly stressing the benefits of its unified enterprise software architecture and features such as Kerberos, Active Directory, and Enterprise UDDI Services.
But, more fundamentally, Microsoft is positioning its products as quasi-commodities (within a broad architectural framework) that are targeted aggressively at various market segments. The company’s recent server software releases are noticeably less monolithic and more function-limited in architecture than previous versions. In addition, Microsoft has deliberately excluded a lot of promised new functionality from the basic "Longhorn" release (as it did from the base Windows Server 2003 release). Instead, Microsoft will continue introduce many new features at various times in the form of “layered” (and separately licensed) add-ons. By productizing various features separately from the basic server OS, Microsoft is giving itself the flexibility to position those products as agile competitors in market niches feeling the commoditization crunch.
For enterprises, these are good signs and good times. Commoditization promises to reduce software licensing costs, increase vendor competition and innovation, and encourage standards-based interoperability. Microsoft is smart enough to know that it's counterproductive to resist this unstoppable trend.