What is cloud computing?

"Cloud computing is immensely popular with companies and government agencies in search of revolutionary cost savings and operational flexibility", says Mike Armistead, VP corporate development, Fortify Software.

The two major benefits of cloud computing are its adaptability and cost reduction. "An enterprise can get computing resources implemented in record time, for a fraction of the cost of an on-premise solution, and then shut them off just as easily. IT departments are free to scale capacity up and down as usage demands at will, with no up-front network, hardware or storage investment required. Users can access information wherever they are, rather than having to remain at their desks," explains Armistead.

The costs of cloud computing are related directly to what a company is using. Companies are only paying for whatever services they need and providers are able to spread their costs across multiple customers.

Categorising cloud computing

Cloud computing can be categorised into four deployment models, which are defined by the US National Institute of Standards & Technology (NIST) as the private cloud, the community cloud, the public cloud and the hybrid cloud.

The private cloud is an infrastructure leased by a single organisation and operated solely for that organisation. The community cloud is where the infrastructure is shared by several organisations with common requirements such as security issues. The public cloud is an infrastructure which is owned by an organisation which sells cloud services to the general public and finally the hybrid cloud is an infrastructure made up of two or more of the cloud modes.

For a lot of companies, confusion still remains over how to get the best out of the concept. "Realising the cloud's benefits is greatly determined by the trustworthiness of the cloud infrastructure - in particular the software applications that control private data and automate critical processes. Cyber-threats increasingly target these applications, leaving IT organisations forced to sub-optimise the cloud deployments containing this software, limiting flexibility and cost savings," says Armistead. "Assuring the inherent security of software, therefore, is a key factor to unlock the power of cloud computing and realise its ultimate flexibility and cost benefits," he adds.

According to industry analysts, deployment will be a matter of timing for the Middle East: "Of course you will see some early adopters of the technology but the pragmatic CIOs are the ones who are looking at cloud from a cautious viewpoint, for them it's not a question of if but a question of when. When do they think their organisation will be ready to adopt the cloud?" Jyoti Lalchandani, vice president and regional managing director, IDC says.

Cloud service models differing in popularity

The three major cloud services on offer are software as a service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS). SaaS is the most established of all the systems, security is controlled by the vendor and the customer controls little to do with the application. PaaS is an emerging cloud service model which differs greatly from SaaS. "The customer is able to develop applications and deploy onto the cloud infrastructure using programming languages and tools supported by the cloud service provider. They are not able to control the actual infrastructure - such as network, OS, servers or storage - the platform itself," explains Armistead.

IaaS is an extension on PaaS with even more infrastructure exposed to multi tenant users. The customer is able to deploy and run arbitrary software, including operating systems and deployed applications.

"While SaaS gained popularity as an alternative to on-premise software licensing, the models that are driving much of the current interest in cloud computing are the PaaS and IaaS models. Enterprises are especially drawn to the alternative development infrastructure and data centre strategies that PaaS and IaaS offer. At this point in time, smaller enterprises seem to have more traction with PaaS, enabling them to rapidly bring websites to market; whereas larger enterprises are more comfortable beginning their cloud deployments with an existing application moved to an IaaS cloud service," concludes Armistead.