Cloud Computing

Defination:
Cloud computing is a set of technologies that allows computing applications and data to be exposed as a set of services from a pool of underlying resources.

The foundation of cloud computing comprises of data centers (servers, storage, networking), the business applications and middleware, virtualization software and of course opearting systems.

Benefits:
Scalability: Cloud computing allows an organisation to scale up or down their IT requirment quickly and efficiently without hampering productivity. It cuts down the time involved in buying and setting up the additional hardware, software and other necessary resources everytime a new service is required.

Lower infracture cost: As Cloud computing is available in pay as you go basis and the resources can be pulled out and restored dynamically, a lots of cost related to maintainance, administration etc are reduced.

Better Utilization: As the IT infracture is nothing but pool of resources. It reduces wastage and improves resource utilization. It also cuts down the downtime.

Deployment models:
There are basically three types of cloud - Public, Private and Hybrid.
Public Cloud: This is essentially an external cloud, provided by service provider. The public cloud is available in pay as you go basis. The benifits of moving to public clould are many. with the key one being that you don't have to worry about managing the underlying IT infracture.

Private Cloud: A Private cloud refers to having your own cloud computing infrastructure. It provides better control over the entire process of information processing. This helps reduce costs, Improves response time, and provides greater flexiblity.

Hybrid Cloud: Its a cloud computing environment that consists of internal/ external providers i.e. a mix of public and private cloud.

Cloud services:
Cloud Services are devided into three parts - SaaS, IaaS, and PaaS.
SaaS: Its the software application as a service through the cloud.

IaaS: Its infracture as a service through the cloud. The resources comprises of storage, hardware, servers, networking components etc.

PaaS: Its Platform as a service through cloud. This components of the cloud computing can be defined as a set of software and product development tools that allows developer to create applications on the provider's platform.