Friday, January 20, 2012

What is Cloud Computing ? How does it work ? [Explanation in Depth ]



We all have been hearing about Cloud Computing these days. Most of us even say that Cloud Computing is definitely the future, but do we actually know what exactly is Cloud Computing or how how it works. Lets have  a deep look on this.


 Yes, first I would like to clarify 2 things :
  1.   If you have heard people saying that Cloud Computing is the future , then you have  heard it right. Its true, Cloud is definitely the future.
  2. If you ever had a  thought in your mind  that Cloud Computing is in  some way related to the clouds in the sky then you are wrong. There is no such connection between Cloud Computing and the 'Clouds' in the sky.  
Now, before we begin with the explanation- lets have a simple definition , i.e. -


What is 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 metered service over a network (typically the Internet).

    Cloud computing is a marketing term for technologies that provide computation, software, data access, and storage services that do not require end-user knowledge of the physical location and configuration of the system that delivers the services.It is a general term for anything that involves delivering hosted services over the Internet. 

   These services are broadly divided into three categories:
  •  Infrastructure-as-a-Service (IaaS)
  •  Platform-as-a-Service (PaaS)
  •  Software-as-a-Service (SaaS)

The name cloud computing was inspired by the cloud symbol that's often used to represent the Internet in flowcharts and diagrams.


  A cloud service has three distinct characteristics that differentiate it from traditional hosting.     They are 
  • It is sold on demand -- typically by the minute or the hour
  • it is elastic -- a user can have as much or as little of a service as they want at any given time
  • the service is fully managed by the provider (the consumer needs nothing but a personal computer and Internet access). 
Significant innovations in virtualization and distributed computing, as well as improved access to high-speed Internet and a weak economy, have accelerated interest in cloud computing.  A cloud can be private or public. A public cloud sells services to anyone on the Internet. (Currently, Amazon Web Services is the largest public cloud provider.) A private cloud is a proprietary network or a data center that supplies hosted services to a limited number of people. When a service provider uses public cloud resources to create their private cloud, the result is called a virtual private cloud. Private or public, the goal of cloud computing is to provide easy, scalable access to computing resources and IT services.

Infrastructure-as-a-Service (IaaS)  - Infrastructure-as-a-Service like Amazon Web Services provides virtual server instance API) to start, stop, access and configure their virtual servers and storage. In the enterprise, cloud computing allows a company to pay for only as much capacity as is needed, and bring more online as soon as required. Because this pay-for-what-you-use model resembles the way electricity, fuel and water are consumed, it's sometimes referred to as utility computing.
Platform-as-a-service (PaaS) -  Platform-as-a-service in the cloud is defined as a set of software and product development tools hosted on the provider's infrastructure. Developers create applications on the provider's platform over the Internet. PaaS providers may use APIs, website portals or gateway software installed on the customer's computer. Force.com, (an outgrowth of Salesforce.com) and GoogleApps are examples of PaaS. Developers need to know that currently, there are not standards for interoperability or data portability in the cloud. Some providers will not allow software created by their customers to be moved off the provider's platform.
Software-as-a-service (SaaS) - In the software-as-a-service cloud model, the vendor supplies the hardware infrastructure, the software product and interacts with the user through a front-end portal. SaaS is a very broad market. Services can be anything from Web-based email to inventory control and database processing. Because the service provider hosts both the application and the data, the end user is free to use the service from anywhere.

How does it Work?
   Lets take a small example :  Let's say you're an executive at a large corporation. Your particular responsibilities include making sure that all of your employees have the right hardware and software they need to do their jobs. Buying computers for everyone isn't enough -- you also have to purchase software or software licenses to give employees the tools they require. Whenever you have a new hire, you have to buy more software or make sure your current software license allows another user. It's so stressful that you find it difficult to go to sleep on your huge pile of money every night.
    Soon, there may be an alternative for executives like you. Instead of installing a suite of software for each computer, you'd only have to load one application. That application would allow workers to log into a Web-based service which hosts all the programs the user would need for his or her job. Remote machines owned by another company would run everything from e-mail to word processing to complex data analysis programs. It's called cloud computing, and it could change the entire computer industry.

Download Ebooks


Cloud Computing for Dummies




Cloud Computing :

Principles, System & Architecture




Cloud Computing : A practical Approach



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Video Lecture 
What is Cloud Computing?



Explanation of Cloud Computing 



Explanation



How does it Work?




Basics 



Future of Cloud Computing in IT Companies


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