Glossary of Terms for computing and virtualization
October 11, 2010
By Leslie T. O'Neill
Several different phrases are used to discuss cloud computing and virtualization. A few key words are crucial to understanding these technologies.
Cloud computing: Standardized, scalable and elastic computing capabilities that are delivered over the Internet on demand.
Infrastructure as a Service (IaaS): Infrastructure equipment, including hardware, storage, servers and networking, that is delivered as a service on a per-use basis or by subscription; one of three main categories of cloud computing.
Pay as you go: Cost model for cloud services that refers to both subscription-based fees and per-use fees charged by the service provider.
Platform as a Service (PaaS): Operating systems and associated services delivered by a cloud provider over the Internet; one of three main categories of cloud computing.
Software as a Service (SaaS): Applications delivered as a service instead of purchased and installed on the customer's computers; the most prevalent type of the three categories of cloud computing.
Virtualization: Usually refers to server virtualization, which is software that divides a physical machine into many separate virtual machines, each with its own operating system and applications that share the computer's physical resources.
Leslie T. O'Neill is a writer based in Pleasanton, CA.