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Slideshow: Top 20 Government Cloud Service Providers

One of the IT industry’s big experiments -- the use of commercial cloud services by federal agencies -- is about to get underway. But this high-potential launch is already off to an inauspicious start, with key vendors such as IBM and Google absent from the lineup and obscure specialists serving as lead contractors.

After more than a year of planning, the General Services Administration last month released the names of 20 companies that will be providing infrastructure as a service (IaaS) through Apps.gov, its cloud computing portal. The offerings -- virtual servers, cloud storage, and on-demand Web hosting -- are “coming soon,” according to GSA.

How this plays out could have long-term implications for both federal IT operations and the commercial cloud market. At federal CIO Vivek Kundra’s prompting, government agencies are looking for cloud solutions, so it’s a ready-made market if cloud vendors are able to deliver solutions that meet the government’s security and performance requirements.

Yet the first round of vendors approved to provide those services is surprising, both for who’s in and who’s out. IBM, Google, Rackspace, and Terremark are conspicuously absent from the GSA's list of cloud vendors, which combined into 11 teams.

To see Who’s Who among GSA’s approved list of cloud service providers, check out our image gallery here.

As you would expect, some of the heavyweights of the cloud services market made it through GSA’s vetting process. Amazon, AT&T, Dell, Microsoft, Savvis, and Verizon will all be delivering on-demand IT resources through Apps.gov. Among major defense contractors, General Dynamics Information Technology is in the mix.

However, some lesser known tech companies -- Autonomic Resources, Computer Literacy World, Computer Technologies Consultants, and Eyak Technology -- have also been given a green light by GSA to provide cloud services to federal agencies and departments.

If you’ve never heard of those companies, that’s because they’re specialists that qualify for government contacts as small, in some cases “disadvantaged,” businesses. Anchorage-based Eyak Technology, for example, is owned by native Alaskans of the Eyak tribe.