“ 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. ”
Essential Characteristics of cloud computing is given bellow :
On-demand self-service:
A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider.
Broad network access:
Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, tablets, laptops, and workstations).
Resource pooling:
The provider’s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand.
Measured Service:
Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.
Rapid elasticity:
Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be appropriated in any quantity at any time.
Advantages of Cloud Computing
1.Lower computer costs:
1-No need of a high-powered and high-priced computer to run cloud computing’s web-based applications.
2-Since applications run in the cloud, not on the your desktop PC, your desktop PC does not need the processing power or hard disk space demanded by traditional desktop software.
3-When you are using web-based applications, your device can be less costly, with a smaller hard disk, less memory, more efficient processor
4- In fact, your PC in this scenario does not need a CD or DVD drive, as no software programs have to be loaded and no document files need to be saved.
2.Improved performance:
1- Computers in a cloud computing system boot and run faster because they have fewer programs and processes loaded into memory.
2 -With few large programs hogging your computer’s memory, you will see better performance from your PC.
3.Reduced software costs:
Instead of purchasing expensive software applications and resources, you can get most of what you need for free. • mostly cloud computing applications today, such as the Google Docs suite.
4.Instant software updates:
1- Another advantage to cloud computing is that you are no longer faced with choosing between obsolete software and high upgrade costs.
2- When the application is web-based, updates happen automatically available the next time you log into the cloud.
3- When you access a web-based application, you get the latest version without needing to pay for or download an upgrade.
5.Device independence:
1 -You are no longer tethered to a single computer or network.
2- Changes to computers, applications and documents follow you through the cloud.
3- Move to a portable device, and your applications and documents are still available.