Developers perceive Amazon and Google as being dedicated to the concept of a public cloud and the two vendors most likely to execute a public cloud strategy. Consequently, Amazon's and Google's public clouds are the ones most frequently adopted, according to an analysis by Evans Data of its developer surveys.
Likewise, developers view IBM and VMware as the two vendors most dedicated to creating the private cloud and most likely to execute a private cloud strategy.
Microsoft is sometimes cited as being out of step with cloud computing due to the heavy Windows orientation of its Azure cloud, although it has also broadened it to include open source technologies such as PHP.
Microsoft now supports many Internet and Web services standards but hasn't always advocated open standards at key junction points for competing systems, such as Linux and Unix. And it wants to continue charging for each copy of Windows used on a server, even if Windows is running in a virtual machine. Cloud computing thrives on the ability to proliferate virtual machines without incurring a linear run up in license charges.
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