Is Presentation Virtualization Yesterday's Technology?

You’ve considered consolidating servers. Your numbers look, or indeed are, very good. Virtual servers have already or will, reduce costs. Now, those vendors offering server virtualisation are offering  hosted virtual desktops – as well. But is this not what Server Based Computing already gives you?
Desktop maintenance has long been a cost that’s considered too high. PCs have energy consumption and heat output that provide numbers that are ripe for reducing. Indeed, with a PC being a sizeable device, there’s an opportunity to reduce the physical desk space required, allow greater user density and reduce valuable office space. Deploying a more maintainable, more energy efficient  user device is often a sound investment to improve a company agility and keep costs to a minimum.
Virtualization worked for the servers. Desktops? Time to make those hefty and expensive desktops… thinner?
Drivers for such “thin client” deployments are, and indeed have been for a while, straightforward:
•     Reduce desktop management costs
•     Supporting application software on diverse hardware
•     Ensure your data remains accessible and secure, and indeed
•     Provide secure data access for mobile or remote workers
A thin-client solution supports not only that all important reduction in desktop management costs but, can facilitate supporting applications on diverse hardware; allowing your company to remove the need to standardise on specific hardware platforms that support a ‘gold build’ image. Thin Client allows deployment of a smaller, energy efficient device instead of a power hungry and heat spouting PC: maybe even facilitate a Bring Your Own Computer model; better enable hot-desking; or a work-from-home policy.
Thin-client it is.
Let us introduce Desktop Virtualization: bring in thin-clients.
Be more agile.
Save money.
Improve the bottom line.
But a thin client device connecting to … what?
Server Based Computing
A few years ago the predominant solution to connect to was based around a Microsoft Terminal Services based solution. A single server could support many independent sessions. Early adoption focused on remote access, running multiple user sessions on a servers in the data centre became adopted as an Enterprise Solution. A number of vendors catered for better management of those Terminal Servers – Citrix, Propalms, Quest, 2x and others all developed tools to wrap around terminal services that delivered applications, even full desktop sessions, to thin devices.
This “Server Based Computing” – or Presentation Virutalisation as its also known – facilitated remote working, off-shoring, wide area network deployments of data intensive applications. Central administration, reduced installation time, better management meant that Presentation Virtualization deployment saved organisations time and money.
Presentation Virtualization wasn’t a perfect solution. Graphically intensive applications didn’t work well. Peripheral interaction be it printers, USB devices, PDA, audio was cumbersome at best. Some applications did not sit well in a shared environment.
With a successful Presentation Virtualization service you need to:

• Build one build image and replicate it across the server farm
• Incorporate a user environment virtualisation solution as users move between servers
• Provide peripheral support to users’ connection to USB devices
• Provide solutions to manage remote printing and scanning requirements
• Validate the application  deployment process
• Manage server performance to ensure that the user experience was as good as it can be

Although Presentation Virtualization was a great solution for many, the solution was not ubiquitous for all.
Hosted Desktops
Today server virtualisation has expanded to allow Hosted Desktops to be depolyed.
There have been huge improvements in the graphical capabilities of hosted desktops;  USB, PDA and audio device interaction is much improved over previous Presentation Virtualisation solutions. Citrix’s HDX technologies, or Pano Logic’s Console Direct both enable devices to have their hosted desktop performance appear little different from that of a standard PC.
Yet, Hosted Desktops cannot simply be a standard desktop virtualized.  There are far more desktops than servers. Projects that adopted a similar P2V model for desktops that was implemented for servers find such a solution does not scale effectively and so struggles to provide a return on investment.
A successful Hosted Desktop projects should :

• Minimise disk instances for each virtual desktop
• Incorporate a user environment virtualisation solution as users move between desktops
• Provide peripheral support to connection to their local devices
• Provide solutions to manage remote printing and scanning requirements
• Validate the application  deployment process
• Manage host and desktop performance to ensure that the user experience was as good as it can be

From this, a Hosted Desktop solution has essentially the same issues as with a Presentation Virtualisation environment. Yet, now you’ve to manage not only the desktop environment, but the virtualisation environment as well in addition to management tools to maintain the environment for users.
Desktop Virtualization is more than Hosted Desktops
Is Presentation Virtualisation yesterday’s technology?
To be able to deliver a Desktop Virtualization is not simply a question of hosting your desktop  in the data centre as you would do a virtual server. Benefits of Desktop Virtualization come from better management of that environment – which is not simply moving it from the office to the data centre.
Presentation Virtualization does not provide a standard desktop operating system environment for each user as with many hosted desktop solutions; and this has meant that pure Terminal Services or PresentationVirtualization solutions are not always possible.
Many organizations have found that a Presentation Virutalisation solution has been able to give them an effective return on investment. With the introduction of Hosted Desktops, its possible to compliment a Presentation Virutalisation solution to cater for a wider range of user requiremetns – “Server Based Computing” is now more than simply Terminal Services.
Presentation Virutalisation allows for high density of user sessions per server. Fewer servers means fewer devices to manage, fewer environments to maintain. In a number of deployment scenarios –  especially around task worker application deployment –  Presentation Virtualization is an effective and cost effective solution for deploying a thin client environment.
Its hardly a paradox – Presentation Virtualization is undoubtedly a technology for today and indeed, many tomorrows.