XenDesktop: High Performance and Flexibility

• By Harry Labana
• 01/01/2010

As our industry defines best practices for large-scale deployment of desktop virtualization, user experience has become the proving ground for IT and end users. XenDesktop provides advanced HDX technologies to deliver a high-definition experience on any device, over any network. When comparing features, VMware View lacks several capabilities that users expect to see, including PC-like Flash experience, broad smartcard support, voice, video and webcam support, VoIP softphone compatibility, bi-directional audio, WAN optimization support, single sign-on and 3-D professional graphics capabilities to name a few.

As customers quickly find out, delivery protocols are just one part of the equation. Optimizations are needed across the entire delivery infrastructure.

Here XenDesktop comes out ahead. To prove this, Citrix conducted internal tests to measure protocol throughput. (Note: Tests can easily be replicated using publicly available tools and WAN emulators. A WAN emulator is not needed when testing in a LAN environment.) A load-testing tool ran a series of randomized applications including Microsoft Office, Web content, and Flash audio and video. We ran the tests for 30 minutes or more with no Flash acceleration, redirection or throttling on either product. Chart 1 shows the results.

To get a view of performance requirements to address professional 3-D graphics users-even over the WAN-we tested XenDesktop and HDX 3D against the hardware version of PC over IP (PCoIP). VMware has since released a software version of Teradici's PCoIP. HDX 3D consumed 90 percent less bandwidth than hardware PCoIP-even at the lowest performance settings (see Chart 2).

The user experience of PCoIP degraded significantly as bandwidth decreased from an open LAN to lower speeds. HDX 3D remained stable while PCoIP began to falter. At 2Mbps, PCoIP was unusable. It is logical to conclude that the software version of PCoIP will not perform as well as the hardware version. PCoIP will not work in a Microsoft Remote Desktop Services (RDS) environment, further reducing potential total cost of ownership benefits.

Achieving ROI with Every Use Case
To achieve strong ROI with desktop virtualization, we believe there are four factors to consider:

1. On-Demand Applications: The cost and complexity of desktop management is a direct result of applications running on each user's desktop. Integrating the capabilities of XenApp technology into XenDesktop 4 significantly improves ROI by making application delivery an integrated part of overall desktop management.
2. Flexible Delivery Models: VDI only serves a subset of users. XenDesktop 4 includes FlexCast delivery technology, allowing IT to mix-and-match delivery scenarios, which can be executed from a centrally managed solution.
3. Network Infrastructure Costs: By optimizing user experience at every point-endpoint, network and data center-HDX provides the best user experience using the existing network infrastructure.
4. Open Architecture: XenDesktop fully supports Citrix XenServer, Microsoft Hyper-V, VMware ESX and VMware vSphere, giving customers choice. View is locked into the VMware hypervisor platform and the required version may not match the version deployed.

Combining inadequate performance with a single, VDI-only, locked-in architecture is not the way to improve ROI and end-user satisfaction. Customers need high virtual desktop performance and flexibility that support an increasingly distributed workforce to achieve the best ROI given the diverse requirements. Citrix XenDesktop 4 with HDX and FlexCast technologies helps customers achieve this goal.