Feeds

Rethinking desktop virtualisation

It’s not just thick versus thin

Gartner critical capabilities for enterprise endpoint backup

Desktop Virtualisation It used to be simple. Users could either run a local operating system, or use a thin client with screen, keyboard and mouse talking to an operating system running on the server. Today there are many models of desktop virtualisation, and few safe assumptions.

It used to be the case that virtual desktops could not handle graphically-intensive applications, for example; but Microsoft’s RemoteFX, which is a feature of Windows Server 2008 R2 SP1, allows GPU virtualisation, in which multiple virtual desktops share a GPU on a Hyper-V server. If you put together faster networks and innovations in virtualisation like this one, the performance gap between virtual and local desktop clients narrows significantly.

Further, it is no longer true that a virtual desktop necessarily runs remotely. VMWare View, for example, is a complete system for composing, deploying and managing desktop images, which are accessed remotely by users running a local View Client.

View Client includes a neat option called Local Mode, in which users can download a virtual desktop onto their client device and take it offline. The user can catch a flight across the Atlantic, continue to work while offline, and sync up their changes to the server once reconnected.

Five ways to skin a cat

So how many kinds of desktop virtualisation are there? Intel distinguishes five models:

  • Terminal Services: the old remote desktop model, based on sessions running on the server and accessed by remote desktop.
  • Virtual Hosted Desktop: each user has a VM running on the server, accessed by remote desktop. This is inherently less efficient than a session to a shared desktop, but better for isolation and security.
  • OS Streaming. In this model, a diskless client downloads an OS image from the server on boot. Streaming means that only the necessary software is transmitted on demand.
  • Client side virtual container. This is the VMWare View Client Local Mode by another name. The local client hosts a VM downloaded from the server.
  • Application virtualisation. In this model, users have a standard desktop with few applications fully installed. Most applications are packaged and installed on demand.

The term 'virtualisation', already overburdened when applied to desktops, has a different meaning when applied to applications. It describes how applications can be packaged into a self-contained bundle that runs without dependencies and without impacting local resources like the Windows registry.

The trade-off is greater reliability and ease of deployment, versus lower efficiency with respect to disk space and shared resources. Examples are VMWare ThinApp, Microsoft’s App-V – which is part of the Desktop Optimization Pack – and Citrix XenApp, which can work in conjunction with App-V.

While you can argue whether merely using application virtualization qualifies as true desktop virtualisation, there is undoubtedly synergy between the two. If you simplify application deployment, this also simplifies the building of desktop images, however they are deployed.

Citrix FlexCast with XenDesktop supports all five of Intel’s desktop virtualisation models, though it uses different names. The Hosted Shared model uses remote sessions for maximum efficiency. Local VM is the XenDesktop approach to a client side virtual container.

Streamed VHD covers the OS streaming model. Hosted VDI is a virtual hosted desktop, a complete VM running on the server. The idea behind FlexCast is that organizations can support all these different approaches, along with application virtualisation, through a single solution.

One of the attractions of desktop virtualisation is that users are insulated from the limitations of specific devices. Apple’s fashionable iPad is an example. It is a locked-down device that runs iOS; yet fire up an app like Citrix Receiver or VMWare’s View Client for iPad, and it becomes a Windows desktop; not so sexy, perhaps, but ideal for getting on with your work.

The bottom line is that desktop virtualisation has evolved into a flexible and capable approach with few limitations, and obvious advantages for management, security and maintenance. The virtual revolution is not just for servers. ®

5 things you didn’t know about cloud backup

More from The Register

next story
Raspberry Pi B+: PHWOAR, get a load of those pins
More USB ports than your laptop? You'd better believe it...
So, Apple won't sell cheap kit? Prepare the iOS garden wall WRECKING BALL
It can throw the low cost race if it looks to the cloud
Now that's FIRE WIRE: HP recalls 6 MILLION burn-risk laptop cables
Right in the middle of Burning Mains Man week
Apple promises to lift Curse of the Drained iPhone 5 Battery
Have you tried turning it off and...? Never mind, here's a replacement
Apple's iWatch? They cannae do it ... they don't have the POWER
Analyst predicts fanbois will have to wait until next year
Super Cali signs a kill-switch, campaigners say it's atrocious
Remote-death button bad news for crooks, protesters – and great news for hackers?
HUGE iPAD? Maybe. HUGE ADVERTS? That's for SURE
Noo! Hand not big enough! Don't look at meee!
AMD unveils 'single purpose' graphics card for PC gamers and NO ONE else
Chip maker claims the Radeon R9 285 is 'best in its class'
prev story

Whitepapers

A new approach to endpoint data protection
What is the best way to ensure comprehensive visibility, management, and control of information on both company-owned and employee-owned devices?
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Maximize storage efficiency across the enterprise
The HP StoreOnce backup solution offers highly flexible, centrally managed, and highly efficient data protection for any enterprise.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.