Scalability and Service Continuity are not equivalent terminologies in Cloud Computing. A service of cloud computing is generally provided to customers to ensure a capability to scale, but the fact remains that there are people who can consider a cloud service as a safety net for interruptions. The idea to protect against interruptions and failures is achieved by hardware redundancy, preparing copies of applications or web services hosted in the cloud and they are ready to use only when there are problems internal infrastructure. Scalability is a feature of Cloud Computing.
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