Desktop virtualisation review: A buyer's guide to Citrix XenDesktop 5

Desktop virtualisation enables organisations to manage and run their desktop operating systems and applications from the data centre, with client devices carrying out as little or as much processing as is required. Citrix's XenDesktop 5 is one of the leading desktop virtualisation applications on the market, competing with VMWare, Microsoft and Oracle.

Desktop virtualisation with Citrix XenDesktop 5

Citrix has experience in thin client computing dating back to 1989. When it acquired XenSource - and its Xen hypervisor - in 2007, it strode into the complementary server and desktop virtualisation markets.

Now on version 5, Citrix's XenDesktop is one of the leading desktop virtualisation applications on the market, competing with VMWare, Microsoft and Oracle.

Desktop virtualisation enables organisations to manage and run their desktop operating systems and applications from the data centre, with client devices carrying out as little or as much processing as is required.

Among the benefits of desktop virtualisation are reduced IT expenditure on traditional desktops; lower energy costs through thin client adoption and server consolidation; and reduced physical desk space. Workers can access their desktop and applications from any network or web-enabled device, because their applications are hosted on the server.

Citrix XenDesktop has had major updates every 18 months, with each alternate point release improving either the end user or administrative aspects. Version 5, released in December 2010, has new tools designed to make it easier for administrators to manage and roll out virtual desktops.

Hybrid approach to virtual computing

The platform itself supports four types of IT infrastructure, delivering data to the end point using Citrix's FlexCast technology:

  1. Hosted shared computing
  2. Virtual desktop infrastructure
  3. Streamed environment
  4. Virtual machine at the endpoint


Hosted shared computing

The first is "hosted shared" or "thin client" computing, where the server carries out all processing and sends information to a screen.


Virtual desktop infrastructure

Second is a hosted virtual desktop infrastructure (VDI), where the clients each run their own virtual machines and carry out some degree of processing.


Streamed environment

Third is a streamed environment, where the client carries out more of the processing.


Virtual machine at the endpoint

The last is where the XenDesktop software is running in a virtual machine on a 'thick client' endpoint, such as a mobile computer, which can run applications offline. However, data can still be synchronised periodically with the server.

Many organisations employ a hybrid approach, where they can offer meatier desktop computing performance to certain staff, while most access their desktop over the network, says Amitabh Sinha, Citrix vice-president and general manager, Enterprise Desktops Group.

Citrix XenDesktop 5 features strengthen management tools

Amitabh Sinha says version 4 of XenDesktop focused on improving the user experience, with version 5 strengthening the management tools, as did version 3. "We spent a lot of time looking at the pain points in XenDesktop and asking our customers what was giving them sleepless nights. Overall, they wanted us to simplify desktop virtualisation for large-scale rollouts, ease configuration, reduce installation times and make it easier to operate workflows," says Sinha.


Administrator tools

Consequently, Citrix created two new administrator tools for XenDesktop 5. The Desktop Studio console simplifies labour-intensive admin tasks such as building, testing, deploying and rolling back images. Desktop Director provides an administrative overview of the virtualised desktop infrastructure, giving real-time status and statistics. It also lets the IT department take common remote corrective actions like sending messages to users, shadowing sessions and restarting desktops.


Support for tablets and smartphones

The latest version supports a wide range of tablets and smartphones with the Citrix Receiver client software, and can "touch enable" existing enterprise applications so they can run on touchscreen tablets such as the Apple iPad or Blackberry PlayBook.


XenVault: local encrypted data space

The receiver software itself incorporates a technology called XenVault which creates an encrypted data space that can be used by corporate applications, with the ability to securely and remotely wipe corporate data.

Desktop virtualisation issues to consider: capacity and licensing

For organisations considering making the move to desktop virtualisation, Sinha says that server and network capacity may present concerns. However he argues that virtualised applications are network-optimised, and server costs are falling as their density increases. "We get 100 to 120 virtualised desktops to a server. It used to be 40 a few years ago. In addition, storage costs are halving every 18 months."

However, for some business applications, licensing in a virtualised environment may still be a problem with suppliers charging for applications in different ways - such as per CPU, per processor core, or per user. "Licensing is always a topic of deep interest amongst our customers. Because there is the ability to scale desktops fast, it can be an issue," admits Sinha.

Case study: Desktop virtualisation at Cancer Research UK

Cancer Research UK: hybrid model affords hot-desking and server consolidation
Cancer Research UK employs 1200 staff at its London headquarters. The organisation decided to move from a Windows-based client-server IT infrastructure to desktop virtualisation at the end of October 2010 when it moved into a new office building.
Jane Swindle, IS service manager at Cancer Research, says occupancy studies found desks and desktop computers were only 50% occupied on average at any given point, with staff out of the office, in training or attending all-day meetings. The organisation felt it could operate with 70% of the desks and computers it previously had.
Another argument in favour of desktop virtualisation was that it would mean staff could hot-desk, logging into their desktop from any work machine, home PCs and mobile devices. They could also re-organise quickly into project teams, which traditionally took huge change to achieve, says Swindle.
Meanwhile the Cancer Research office needed to upgrade the Windows XP desktop and laptop infrastructure to Windows 7, while reducing IT hardware costs by replacing thick clients with thin clients.
Cancer Research completed its move to desktop virtualisation with Citrix XenDesktop 4 in December 2010. With the new architecture, most processing is done on the server side, sending information through to a network of around a thousand low-cost, low-power IGEL thin clients. However, the organisation still operates 50 Windows 7/Apple Mac thick clients for media and development professionals who need more powerful local processing.
On the server side, Cancer research consolidated around three hundred servers down to a rack of just three HP blade chassis, linked to an EMC Clariion storage array, vastly lowering its datacentre costs. "What was a big room, the size of a netball court, is now a single corridor with 10 cabinets in it. There are cost, space and green benefits," says Swindle.
Cancer Research chose Citrix over Microsoft mainly due to cost, and the fact that Citrix was running an attractive trade-up programme for operating system licenses.
Cancer Research is planning an upgrade to XenDesktop 5 in the next six months and is currently running a test server. It is also looking forward to the administrative enhancements of version 5.
"We do find some of the management features in XenDesktop 4 quite cumbersome. We have also seen some issues around Flash support for some YouTube content, and had issues with viewing documents on our RBS receipt scanning system. But Version 5 seems to address these, and it also allows us to support multimedia, which will reduce our desktop count further," says Swindle.

Analyst Ovum's view of Citrix XenDesktop 5

Citrix XenDesktop 5: user experience and device support
According to Roy Illsley, senior research analyst Ovum, desktop virtualisation represents around 15% of the business PC market, with around 12% being terminal services, a figure that has remained constant over the last 10 years.
Citrix claims to have around three million virtual desktop seats in active use globally (with one of its biggest deployments being 140,000 seats), making it one of the market leaders along with VMWare and Microsoft. Worth noting is that XenDesktop can be deployed on top of Citrix's XenServer server virtualisation platform, as well as competitive hypervisors from VMWare and Microsoft.
Roy Illsley says: "The user experience capability is a particular strength of Citrix, because through its proprietary HDX delivery technology Citrix offers a high-definition user experience for virtual desktops and applications." HDX combines data optimisation and acceleration with third-party technologies such as Nvidia graphics processing on the server side.
Illsley adds that Citrix XenDesktop 5 offers a wide range of client device support, covering Windows, Mac OS, Linux, Solaris, Java and IBM and HP UNIX operating systems. "Ovum considers that the range of client-side technologies makes XenDesktop 5 a leading solution from both the end-user experience platform perspective and the IT perspective."
"Citrix does not have a cloud solution as yet, but for most organisations it has all the other solutions, even the client hypervisor for 'road warriors'. Ovum rates Citrix as a leader in the VDI space, and becomes even stronger with its working relationship and interoperability with Microsoft's solutions," concludes Illsley.
Citrix has a long history of experience in server-based computing, with products dating back to terminal services in the 1990s. It continues to strengthen its desktop virtualisation product, against strong competition from VMWare and Microsoft, in the areas of performance, multimedia, and support for client devices, whilst making its offering attractive on price, as evidenced by Cancer Research. Consequently, Citrix XenDesktop 5 is worthy of consideration for organisations looking to adopt desktop virtualisation.

Citrix XenDesktop 5: five essential features

  1. Supplier: Citrix, founded in 1989
  2. Annual revenues: $1.87bn for fiscal 2010; $1.61bn for fiscal 2009
  3. Product: XenDesktop 5 desktop virtualisation platform
  4. Competitors: Microsoft, VMWare, Oracle
  5. Client/server platforms supported include: Microsoft Windows, Java, Mac OSX, Apple iPhone, Linux, Solaris, HP-UX, IBM AIX, Symbian, IBM OS/2, Windows Server Sun Solaris SPARC, HP-UX PA-RISC, and IBM-AIX2 POWER processors

Video: XenDesktop 5 tutorial

Video: Citrix XenDesktop 5 quick deploy

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