What's the big deal?

So the virtualisation machine has rolled through servers and storage and is now rumbling onto desktop and network virtualisation. The latter is no biggie - virtual private networks anyone? - but the former hasn't taken off as anticipated.

Desktop virtualisation refers to either removing the desktop and replacing it with a thin client device, or retaining the hardware but virtualising the operating system and software. In either instance, the user's desktop is stored as a virtual machine on a central server and delivered to whatever hardware they log on via. This, as with everything, has benefits and challenges.

The most obvious challenge, locally, is bandwidth, although Citrix corporate account manager Cary de Sousa is quick to point out that his company's technology is bandwidth-light, so this isn't necessarily a problem for his clients. VMware regional director Chris Norton notes that bandwidth hasn't been a problem inside the country, in terms of availability, and that companies have access to as much bandwidth as they are prepared to pay for. Which is the problem, but that's another article. The vendor also has acceleration and optimisation tool sets available to overcome this sort of problem, he says.

Bandwidth aside, there are other challenges. Says EMC's virtual computing specialist Travers Nicholas: “When desktop virtualisation was first introduced, many expected it to be immediately as popular and as powerful as server virtualisation. The very simple reality was that server virtualisation removed devices from computer rooms and data centres, while desktop virtualisation still requires physical devices to exist, as a “portal” or “gateway” into the virtual desktop. This created an interesting capex model, whereby many virtual desktop offerings were similarly priced to traditional non-virtual desktop pricing models. The main overlooked issue was that desktops that were virtualised and hosted centrally were quicker to change, simpler to support, and required less ancillary software products to support them. Most people don't measure how much time they spend on supporting their desktops, and so it was very hard for them to measure the reduction in total cost of ownership after virtualising. That said, many companies that were using a mature approach to measuring their operational costs were able to measure the benefits, and they have undergone transformation.”

Beyond the measurement issue, cost is an issue both for and against. Says Accenture's Manisha Bhoola: “One of the major expectations of desktop virtualisation is a substantial cost saving. While this is true in the long-term, significant capital investments need to be made upfront, and this often deters clients from implementing desktop virtualisation.”

Most people don't measure how much time they spend on supporting their desktops.

Travers Nicholas, virtual computing specialist, EMC

Conversely, says BCX CTO Andy Brauer: “The evolution of the desktop is as a consequence of what's happening in the back-end with servers, etcetera. It's a really ramped-up green screen, but a lot more pretty. The real reason why we're going back to [centralised computing] is the cost of staff running around to maintain/support/fix PCs. If there is a virus outbreak, for example, you need to fix manually. If you use green screen methodology, all you have to do is recover the instance on the server side or mainframe side, which means a lot of automation takes place, which is one of the drivers. Desktop virtualisation enables reduced staff headcount, and allows you to save the tremendous amount of time, and cost, spent in maintenance and support. The cost saving is not in the equipment, it's in the people and data loss.”

As De Sousa notes: “An important benefit of desktop virtualisation is that information and applications - effectively the whole desktop - are streamed to the user and not saved on the device. In the case of a lost or stolen interface device, confidential company information remains safely stored in the data centre.”

That said, it's not just the desktop device that's at issue when it comes to set-up. As Dimension Data principal consultant for Microsoft Solutions, Steven Spirou, says: “One thing holding it up is the cost of the data centre infrastructure to do this. In a typical case, giving a user a virtual desktop means looking at serious server and storage space in the data centre, plus the device cost.

“The other thing is the sheer complexity. Virtual desktop interface (VDI) is often punted as a cost saving but in reality it's also being positioned as a way to handle a poor desktop management problem. Could desktops be managed better? Is VDI a viable or feasible solution giving a real ROI? Lots of other things need to be done. You can't just implement a hypervisor with servers and storage; a desktop management solution needs to go in. You need profile management, you need to look at how you provision desktops, how you manage applications - a lot of which can be applied to physical desktops too - so we're seeing it as a complex infrastructure, with big decisions to be made. Another issue is standardisation. If you do a broad desktop virtualisation roll-out, you need to standardise first and we're seeing [user] resistance there.”

Accenture's Bhoola agrees: “User acceptance is critical to success. Not all use cases can be delivered via desktop virtualisation and may require alternative approaches. For example, roles like graphic design, CAD and engineering are currently ill-suited for desktop virtualisation. Determining the number of users the solution can address is an essential element in calculating ROI. It is vitally important to segment user communities and determine the best candidates.”

The same applies to solutions. “One size does not typically fit all. A mix of products from leading vendors is often required for a best-of-breed solution,” Bhoola says.

Licensing also needs careful consideration. “At least one large local bank was caught by surprise because VDI licensing for Windows sits in Microsoft licensing agreements, so you need to consider what you're entitled to and where you stand from a licensing point of view,” says Dimension Data Microsoft Solutions GM Bradley Bunch.

It's a really ramped-up green screen, but a lot more pretty.

Andy Brauer, CTO, BCX

All is not doom and gloom, though. Beyond the obvious cost and resource savings, desktop virtualisation has some other upsides, as Bhoola notes: “Lower total cost of ownership of applications by up to 40% and desktop workstations by up to 66%, while accelerating ROI. Higher system security with an additional set of security layers. Increased employee satisfaction thanks to consistent, rich desktop experiences regardless of location, connection or computing device. Fast regulatory compliance due to tools such as rule-based policies that enable quick adaptation to more complex regulations.” This last will become increasingly important in South Africa as laws like the Protection of Personal Information Bill are enacted.

Cost considerations, differing use cases, security wins and risks all need to be considered. As with many technologies, what gets implemented will be determined by which pros outweigh which cons on an individual per use basis. There really is no one-size-fits-all.