In many ways it replicates the old structures of mainframe computing when users were equipped with dumb terminals and the intelligence lay in a centralised computing infrastructure. In some aspects, the personal computer came about as a consequence of the limitations of the mainframe approach which meant users were cut out of the loop of innovation as they could only do what they were authorised to do and were dependent on administrators to give them permission to address problems.
Cloud computing differs from the mainframe approach-users have more autonomy in their PCs and instead of being a location-based or company-run computing infrastructure, cloud computing relies on the internet to provide computing resources as a service.
The basic concept is that vast computing resources are available to users from the internet “cloud†rather than in their own premises. Companies such as Google have been keen to promote the concept, especially as its business is already founded on owning giant computing infrastructure that users can tap into.
How does it work?
Cloud computing is a general concept that incorporates Software as a Service (SaaS), Web 2.0 and other technology trends that rely on the internet to satisfy the computing needs of users. Cloud computing is often confused with grid computing- a form of distributed computing composed of a cluster of networked, loosely-coupled computers that act in concert to perform large tasks. In addition, it has much in common with utility computing-the packaging of computing resources such as storage as a metered service in common with other utilities like gas or electricity. Many current cloud computing deployments depend on grid-like structures and are billed for in the same way as utilities.
This usage of other principles has led to some confusion emerging around what exactly constitutes cloud computing, as well as the extent to which it is novel. Oracle CEO Larry Ellison recognised this confusion publicly during a conference last year at which the Wall Street Journal reported him as saying: "The computer industry is the only industry that is more fashion-driven than women's fashion. Maybe I'm an idiot, but I have no idea what anyone is talking about. What is it? It's complete gibberish. It's insane. When is this idiocy going to stop?"
So it's a non-starter composed of industry hype?
Absolutely not. Cloud computing should rather be seen as a natural development of grid and computing utility concepts. Successful cloud architectures have modest or no centralised infrastructure or billing systems and include peer-to-peer networks such as Skype or Bittorrent. Today, cloud computing consists of reliable services which are delivered through data centres and built on servers with different levels of virtualisation technologies. These services are available anywhere in the world with the cloud offering a single point of access for the entire computing needs of the organisation's users. Large and influential companies such as Amazon, Google, Microsoft, Dell and IBM are key commercial exponents of cloud computing and the technology is being adopted by large enterprises such as General Electric, L'Oreal and Proctor & Gamble. It is beginning to gain traction and will not disappear any time soon.
What are the benefits to users?
Cloud computing means that customers do not need to own their own computing and telecoms infrastructure. They can instead access or rent the functionality that they use, paying for only that. As a consequence, they avoid a great deal of capital expenditure and consume their resources as a service. In addition, the sharing of computing power among multiple users leads to better utilisation rates because servers are not left sitting idle.
A side effect of this change in systems structure is that users' computing capacity appears to increase dramatically as customers have no need to engineer their systems for peak loads. Adoption has also been accelerated by greater access to high-speed bandwidth, which is the oxygen of cloud computing. Without the connectivity there can be no cloud.
Is there enough network capacity to support widespread uptake?
Availability of bandwidth is central to the operation of cloud computing and some carriers have concerns that the additional traffic it generates could cause problems.
Cloud computing has the potential to offer businesses significant benefits, but in order to make the most of cloud-based software they must be supported by a fast and reliable network, according to Stephen Beynon, managing director of ntl:Telewest Business. "The convergence of voice and data has caused the UK's ageing telecoms infrastructure to struggle as it cannot provide the bandwidth necessary for these business critical services, which it was not designed to provide. The growing take-up of cloud computing will only exacerbate this problem unless businesses embrace next-generation networks, built specifically for the digital age. As more and more bandwidth is needed to support voice, data and video conferencing services and cloud-based software applications, the adoption of next-generation networks by businesses is rapidly becoming a necessity."
