Dinesh on Java

Cloud computing has been changing how most people use the web and how they store their files. It’s the structure that runs sites like Facebook, Amazon and Twitter and the core that allows us to take advantage of services like Google Docs and Gmail. But how does it work?

Before we dig further into how does cloud computing work, first let’s understand what the term “cloud“ refers to. The concept of the cloud has been around for a long time in many different incarnations in the business world. It mostly means a grid of computers serving as a service-oriented architecture to deliver software and data.

Most websites and server-based applications run on particular computers or servers. What differentiates the cloud from the way those are set up is that the cloud utilizes the resources from the computers as a collective virtual computer, where the applications can run independently from particular computer or server configurations. They are basically floating around in a “cloud of resources”, making the hardware less important to how the applications work.

For example, if you are hosting your website on a local server or from your PC, you must usually select a particular operating system (Windows/Linux/Mac), to determine what software you can run on that particular server. If your site is being hosted in the cloud, there is no need to do that. You can run Windows and Linux programs side by side.

How is that done?

To understand how does cloud computing work, imagine that the cloud consists of layers — mostly the back-end layers and the front-end or user-end layers. The front-end layers are the ones you see and interact with. When you access your email on Gmail for example, you are using software running on the front-end of a cloud. The same is true when you access your Facebook account. The back-end consists of the hardware and the software architecture that fuels the interface you see on the front end.

Because the computers are set up to work together, the applications can take advantage of all that computing power as if they were running on one particular machine. Cloud computing also allows for a lot of flexibility. Depending on the demand, you can increase how much of the cloud resources you use without the need for assigning specific hardware for the job, or just reduce the amount of resources assigned to you when they are not necessary.

Clouds use a network layer to connect users’ end point devices, like computers or smart phones, to resources that are centralised in a data centre. Users can access the data centre via a company network or the internet or both. Clouds can also be accessed from any location, allowing mobile workers to access their business systems on demand.

Applications running on the cloud take advantage of the flexibility of the computing power available. The computers are set up to work together so that it appears as if the applications were running on one particular machine. This flexibility is a major advantage of cloud computing, allowing the user to use as much or as little of the cloud resources as they want at short notice, without any assigning any specific hardware for the job in advance.