“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 and service provider interaction.

By National Institute of Science and Technology U.S.

On-demand network accessmeans acess anytime using network (Internet)

There many words inthe definition we need to inderstand.

Ubiquitous means anywhere or everywhere.









Convenient means easy to get

On-demand network accessmeans acess anytime using network (Internet)

Shared pool of configurable computing resources means collection of shared resources such as network,servers,applications,software,databases used by dofferent users.These collection of computing resources are configurable or configured by user as they want for there use.

Rapidly provisioned and released means resoutces allocated to useres quickly and after there task or work is done, resources released quickly and make available for other users.

Minimal management effort and service provider interaction means users use these computing resources without any techbical efforts without interacting with service provider who is providing these services.

So cloud computing is a model of providing Internet (network) based shared collection of computing resources avaible at antwhere on demand allocated easily,quickly and released quickly after completion of any job or task.All these is easy to get to do.User need little efforts to use these computing resources without interacting or getting help from service provider.

AAdvantages of cloud computing

Effective cost

Installing and maintaining IT infrastructure is a big challenge in organizations and businesses as installing physical hardware like server is very costly, first buying a new server involves high cost then purchasing its software involves cost,installing the server and maintaining it reuires a teams of IT professionals amd employees which also involves cost and updating server time to time as per new reuirements also involves spending of money and time, but if server is taken on rent on cloud decrease the challenge of installing and maintaining physical server and license feews is very nominal and updation of server and its technology is done by cloud computing provider so the effort of updation of server,its technology and its software is minimized, all these will make cost low and effective.

Reliability

Cloud computing or cloud is grid of data centres so if one rent a physical resoruces it is allocated on one data centre whcih its is primary data centre where all its data is store but these sotored data is also stored on one of the other data centre in the data centre ‘s grid so if due to some reasons data is unavailable from the allocated data centre,cloud uses these other data centre to make data and service available.So cloud computing is reliable.

Elasticity

Increasing ro decreasing the resoruces is very flexible in cloud computing, if you reuire more server or resoruces due to some trade or business requirements you just increase the number of resources by incrementing in your cloud accountsettings and if you want todecrease the reuireed resoruces after completion of any task,you just decrement it in cloud account settings and bill is calculated as per usage of more or less resoruces are used.This is called elasticity.

Maintenance

Cloud computing reduces maintenance efforts of organization because they did not reuire to maintain physical hardware resources like a server which involves installation,confiuration,installation of software,updation and time to time maintenance which also need human resoruces like technician,network architect and network administrator, all these burden is now handled by cloud provider.

Also read

SaaS

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PaaS

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IaaS

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