Cloud computing is ubiquitous. It is the most talked about topic nowadays. Businesses talk about adopting cloud software and solutions to reduce operational cost. We use emails which are stored somewhere in a remote location. We upload our pictures to a website that stores them in cloud storage (e.g. iCloud). Our files are stored in Amazon Cloud drive. Our videos are uploaded to YouTube. In today’s world, it is tough to imagine a scenario where cloud computing has not touched our lives. So what exactly is cloud computing?
Cloud computing is a term used to signify a way of accessing software, infrastructure, and computing power from a location other than our own. The resources usually reside in someone else’s computer or distant data centres. Nowadays the reach of cloud computing is so vast that the resources are located in a different country and continent that often we have no clue of the exact location. Think of the emails in your Gmail inbox. The emails do not reside in our computers. Google serves these emails from the servers that reside in any of the data centres located in Americas, Asia, or Europe.
All the elements inside the cloud – applications, platform, and infrastructure – are oblivious to the end users. All the users need is the access devices such as laptops, phones, tablets, etc. and network connectivity to the cloud that is mostly provided by Cloud service providers.
Definitions for Cloud Computing
Cloud computing is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers and other devices as a utility (like the electricity grid) over a network (typically the Internet) – Wikipedia
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. – The National Institute of Standards and Technology (NIST)
“Cloud Computing”, by definition, refers to the on-demand delivery of IT resources and applications via the Internet with pay-as-you-go pricing. – Amazon
…the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer. – Google
According to NIST, the cloud computing model is composed of five essential characteristics, three service models, and four deployment models.
Characteristics
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Service
Models
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Deployment
Models
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On-demand self-service
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Software as a Service (SaaS)
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Public Cloud
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Broad network access
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Platform as a Service (Paas)
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Private Cloud
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Resource pooling
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Infrastructure as a Service
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Community Cloud
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Rapid elasticity
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Hybrid Cloud
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Measured service
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