Cloud computing has been the latest buzz word ever since 2008, promoted by large Information Technology companies such as Google, Microsoft and IBM. It’s very similar in nature to grid computing (An alignment of individual computers serve virtually as a single one, providing combined computing resources) though more focused on the way of consumption rather than the infrastructure itself.

The cloud was used to indicate the Internet. Over time the meaning of “the Internet” has shifted, where it now includes the resources usually perceived as being on the Internet as well as the means to access them.

The term cloud computing came into popular use just a few years before. Some were quick to claim that, rather than a new concept, the term was simply another name for an existing practice. On the other hand, the term has become sufficiently powerful for some existing web applications have to magically turned into examples of cloud computing in action! Such is the power of marketing.

It simply refers to the provision of computational resources on demand via a network. Cloud computing can be compared to the supply of electricity and gas, or the provision of telephone, television and postal services. All of these services are presented to the users in a simple way that is easy to understand without the users needing to know how the services are provided. This simplified view is called an abstraction. Similarly, cloud computing offers computer application developers and users an abstract view of services that simplifies and ignores much of the details and inner workings. A provider's offering of abstracted Internet services is often called The Cloud.

While the specifics may vary from vendor to vendor, you can think of the cloud as a coherent, large-scale, publicly accessible collection of compute, storage, and networking resources. These are allocated via web service calls (a programmable interface accessed via HTTP requests), and are available for short- or long-term use in exchange for payment based on actual resources consumed.

The cloud is intrinsically a multi-user environment, operating on behalf of a large number of users simultaneously. As such, it’s responsible for managing and verifying user identity, tracking allocation of resources to users, providing exclusive access to the resources owned by each user, and preventing one user from interfering with other users. The software that runs each vendor’s cloud is akin to an operating system in this regard.

Cloud computing builds on a number of important foundation-level technologies, including TCP-IP networking, robust internet connectivity, SOAP- and REST-style web services, commodity hardware, virtualization, and online payment systems. The details of many of these technologies are hidden from view; the cloud provides developers with an idealized, abstracted view of the available resources.

When a user accesses the cloud for a popular website, many things can happen. The user's IP for example can be used to establish where the user is located (geolocation). DNS services can then direct the user to a cluster of dedicated servers that are close to the user so the site can be accessed rapidly and in their local language. The user doesn't login to a server, but they login to the service they are using by obtaining a session id and/or a cookie which is stored in their browser.

How it works

What the user sees in the browser will usually come from a cluster of web servers. The webservers run software which presents the user with an interface which is used to collect commands or instructions from the user (the clicks, typing, uploads etc.) These commands are then interpreted by webservers or processed by application servers. Information is then stored on or retrieved from the database servers or file servers and the user is then presented with an updated page. The data across the multiple servers is synchronised around the world for rapid global access and also to prevent data loss.

Benefits of cloud hosting

Cloud hosting benefits the users from various angles. It’s scalability and cost efficient is the commonly known advantages.

As the technology is highly scalable (load balancing, hardware upgrades, etc), website expansion can be done with minimum limitations. Think about the hassle of migrating your website from a shared server to a dedicated server; think about server crash when your website experienced a sudden surge – all these problem can be avoided easily by switching to cloud hosting.

Cost is another huge plus if you need a lot of processing power. Cloud hosting companies charge their users based on the quantity of computing power consumed. It’s like your electricity and water supply bills – it’s pay-per-use thus gone are the days where you need to reserve massive server powers to avoid website crash from sudden traffic surge.