The new virtual reality


Virtualisation is one of the hottest buzzwords in IT, but what does it really mean, asks Karlin Lillington

LISTEN TO industry experts and you would be forgiven for thinking virtualisation - one of the hottest buzzwords in technology - is a universal problem solver.

Lower IT costs, better use of existing resources, easier IT management, security woes addressed - all of these are being claimed in favour of virtualisation. It even provides bonus green credentials, thanks to energy savings and easy facilitation of homeworking.

Sounds good, except that businesses and organisations still find the term confusing, which is hardly a surprise considering "virtualisation" covers such a broad range of technologies and concepts.

"Virtualisation is a much-abused term," acknowledges Francis O'Haire, technical director at Data Solutions. "There are so many types of virtualisation." He likes to describe it as "a technique for delivering a solution to an end user".

Broadly, virtualisation means taking technologies that used to be committed to a specific machine - an operating system, software application or storage - disconnecting them from the hardware, and bringing them into a "virtual" world.

The technology is designed to operate in a virtual environment, running inside a "virtual machine" that can sit on any computer and can be shifted easily from one place to another if computing resources need to be re-allocated.

The virtual machine is a small programme that interacts with the hardware resources of a machine, but acts as if it is its own, independent machine. Many of them can run on a single computer or server, making one computer appear to be many and using hardware resources more efficiently.

One vendor describes virtualisation as "plumbing" - a person doesn't need to know how the water comes out of the tap; all that matters is that it gets there when needed.

At this point, every major hardware and software company has virtualisation products on the market. Microsoft, Citrix, VMware and Symantec are among the big names focusing on virtualisation products, but everyone from hardware makers like Dell to smaller, third-party application companies are getting in on the game.

According to Niall Gilmore, enterprise business manager at Citrix Systems Ireland, most vendors of virtualisation products break the category down into four general areas: desktops, applications, servers and networks.

A user's entire computer desktop, complete with their personalised desktop background and the applications they use, can be delivered to any computer anywhere using virtualisation, says Gilmore.

Applications, meanwhile, are increasingly sold in "virtual" form rather than being loaded directly into a single machine and embedding itself into that machine's operating system. This means they will run in an isolated container on top of any operating system, including virtual operating systems.

As for server virtualisation, O'Haire gives the example of an online ticket vendor that needs to be able to move server resources around to address sudden surges in demand, such as when tickets for a big-name act go on sale and phone and internet sites are inundated with buyers all at once.

The ticket company's network can respond instantly by designating additional virtual servers to those sales.

In such a scenario in the past, someone would have had to set up additional physical servers.

"Now what you have is a dynamic situation where your back-end horsepower is doing the right thing at the right time," O'Haire says.

Network virtualisation means the creation and control of a network using virtual controls rather than hardware. Insecure data communications can be contained inside a safe virtual network, walled off from the main corporate network, for example.

Despite the chatter about virtualisation in recent years, the market has really only begun to take off, according to industry vendors.

"Ninety per cent of servers still aren't virtualised, so there's a lot of opportunity out there," says Bill O'Brien, Microsoft Ireland's server business group leader. He also believes the virtual desktop area is about to take off.

System administrators may find that, while virtualisation will simplify operations in the long run, they would face a new, complex environment to manage if their organisation decided to virtualise its systems.

Still, most organisations are expected to move towards virtualisation, according to industry analysts.

Gartner says virtualisation will be the highest-impact trend in business infrastructure markets in the next four years.

He predicts that the number of virtualised desktops alone will jump from five million last year to 660 million by 2011.