There isn't a standard definition of cloud computing that is used by all service providers, but all definitions of cloud computing will include variations on the following three criteria:
* Multi-tenant - Multi-tenant or shared infrastructure means that multiple companies, departments of a business, or user groups can all use these resources at the same time.
* On demand usage - On demand or scalable usage is another way of saying that you only pay for what you use. If you have 5 users on a service one month, then you only pay for 5. If the next month you have 10, then you pay for 10 that month etc. Another way a cloud service can be scalable is by specific resources.
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Accessible through the Internet - As the Internet grows in both speeds and consistency, more and more businesses are relying on mission critical applications and data that they access through the Internet. This is another key item which defines something as a cloud-based service.
In a true cloud-based computing model, end users may actually not even know where their data resides, as long as they know how to access it, that's all that matters.
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rajamiah123 :
what is cloud computing and what is it used for and is it good or bad