OpenStack is a free, open standard cloud computing platform. It is mostly deployed as infrastructure-as-a-service in both public and private clouds where virtual servers and other resources are made available to users. OpenStack is an open source platform that uses pooled virtual resources to build and manage private and public clouds. The tools that comprise the OpenStack platform, called "projects," handle the core cloud-computing services of compute, networking, storage, identity, and image services.
AWS has EC2, which are scalable virtual networks with Xen and EMR Hadoop based big data analytics. OpenStack, on the other hand, boasts of an IaaS infrastructure. It scales horizontally and is designed to scale on hardware without specific requirements.
Company: Rackspace. Why they're important: Rackspace is an OpenStack founding father.
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