The virtual desktop revolution is here! XenDesktop 4 further widens Citrix’s competitive lead with FlexCast™ technology to deliver the best Windows desktop for everyone in the organization, from task worker to power user. And XenDesktop 4 is an HDX-focused release that provides the best “high definition” user experience in the desktop virtualization market, with better reliability and higher availability than a traditional PC.

From the more than 70 new features in this release, allow me to introduce you to some key new capabilities of XenDesktop 4:

  • HDX MediaStream for Flash (client-side rendering). While server-side rendering remains Citrix’s foundational approach for delivering multimedia content of all sorts, HDX MediaStream for Flash provides an outstanding optimization for Windows online plug-in (client) users on low latency network connections. Leveraging the user device for direct content fetching and rendering, it delivers a high definition user experience and improves server scalability and network bandwidth efficiency by an order of magnitude. This technology supports Flash animations, videos (including HD), and IE-based Flex apps, even video conferencing applications. Citrix competitors do not offer a client-side rendering option for Flash.
  • HDX MediaStream enhanced delivery of server-rendered video. New dynamic frame rate adjustment works in conjunction with bandwidth estimation to optimize video and graphics delivery over WAN and Internet connections. Where bandwidth is plentiful, full frame rate (30 fps) server-rendered video delivery is now available by modifying a registry key [new default is about 24 fps]. When compared to competitors’ server-side rendering, XenDesktop 4 uses significantly less bandwidth to deliver equivalent quality.
  • Enhancements to HDX Adaptive Orchestration. SmartRendering has been enhanced with more intelligence to dynamically select between server-side and client-side video rendering. SmartRendering now considers not only user device type and codec availability but also the real-time bandwidth and latency of the network connection.
  • FlexCast™ desktop delivery technology. Different types of workers across the enterprise need different types of desktops. Some require simplicity and standardization, while others need performance and personalization. With FlexCast™ delivery technology, IT can deliver the best desktop for every user, every time. XenDesktop 4 is much more than just a VDI solution. For task workers where personalization is not needed or desired, XenDesktop 4 supports Hosted Shared Desktops, providing a locked down, streamlined and standardized environment with the lowest cost per user. For design engineers and other power users, HDX 3D for Professional Graphics delivers GPU-enabled desktops hosted on blade or rack workstations.
  • Expanded USB support, including webcams. HDX Plug-n-Play now supports isochronous USB remoting, enabling LAN-connected users to plug in a webcam and enjoy HDX RealTime video conferencing with popular applications such as Microsoft Office Communicator and Skype. This release also supports specialized keyboards (in particular, the Bloomberg keyboard) and dictation devices such as the Philips SpeechMike.
  • Media Foundation support for HDX MediaStream client-side rendering. Media Foundation (MF) is Microsoft’s new framework for digital media, used by Windows Media Player for certain media types on Windows Vista and Windows 7. With XenDesktop 4, multimedia rendering through Media Foundation can, depending on network latency and packet loss, be offloaded from the XenDesktop VDA server onto the user’s Windows or Linux device, greatly improving server scalability. Media Foundation support extends our HDX MediaStream competitive advantage to the latest Windows platforms.
  • New audio codec technology. With the new “Optimized for speech” codec, HDX RealTime delivers clear audio quality to softphone and voice chat users with very modest bandwidth consumption (less than 20 Kbps). HDX MediaStream server-rendered video and music playback benefits from the new “High definition” codec which provides CD-like sound quality. These enhancements leverage version 11.2 of the Citrix online plug-in for Windows.
  • HDX Plug-n-Play flexible multi-monitor support. Application compatibility with multi-monitor configurations has been improved and users now have greater control via the Desktop Viewer toolbar. Supported multi-monitor configurations include special arrangements such as U, L, T, reverse L and inverse T. Screens can be of different sizes, resolutions and orientations.
  • Expanded OS support, including Windows 7. The XenDesktop 4 VDA platform introduces support for Windows 7 (non-Aero) 32-bit and 64-bit, Windows Vista 64-bit and Windows XP 64-bit. With XenDesktop 4, migrating to Windows 7 is as fast and simple as configuring a single master image and assigning users. In addition, the new Citrix online plug-in 11.2 and Web Interface 5.2 releases both support user devices running Windows 7. Smartcard support has been added for Windows 7 and Windows Vista, for Windows online plug-in users.
  • HDX IntelliCache with Citrix Branch Repeater provides tokenized compression and data de-duplication, dramatically reducing bandwidth requirements and improving performance for users at branch office locations. XenDesktop 4 Platinum Edition has been tested with Branch Repeater 5.5. Our measurements indicate a 25 times reduction in bandwidth when using HDX IntelliCache with HDX MediaStream to deliver videos to branch offices.
  • Single sign-on and password control are now included with XenDesktop 4 Platinum Edition, powered by Citrix Password Manager 4.6 SP1, increasing application security while providing users with fast, automated logon to Web, Windows and host-based applications.  
  • Service level monitoring and reporting. XenDesktop 4 Platinum Edition offers enhanced EdgeSight technology to monitor, alert, troubleshoot, and report on the Citrix XenDesktop infrastructure. Administrators can quickly determine where a problem may exist and take action to deliver higher service levels. New summary reports now make it easier than ever to manage a XenDesktop implementation.
  • New EasyCall™ features. With EasyCall call forwarding, users can make and receive voice calls when they’re out of the office, using the office telephone system. EasyCall reduces telephone expenses while providing users the convenience of click-to-call dialing right from their virtual desktop. A new portal, accessible from browsers and iPhones, empowers users to add EasyCall conferences to their calendar and manage call forwarding to multiple telephone numbers.
  • Active Directory multi-forest support enables virtual desktops to be delivered to users located in different Active Directory forests from that in which the XenDesktop infrastructure servers are registered.
  • Site Failover provides a disaster recovery, high availability solution in conjunction with Citrix NetScaler™. Web Interface now supports configuration of a list of disaster recovery farms. When none of the farms in the normal farm list can be reached, Web Interface will automatically try the farms in the disaster recovery list.
  • Site Roaming enables a user to travel to a site served by a different data center, logon at a Citrix Ready thin client, and connect to his or her own virtual desktop even though it is not hosted at that site. Users can always access their own virtual desktops and data, regardless of where they connect from.
  • RDP support. XenDesktop 4 enables users on a locked-down device where they cannot install the Citrix Receiver or online plug-in to access their virtual desktop using RDP. This capability also simplifies moving up to XenDesktop from other desktop virtualization solutions.
  • Extended SDK. The Citrix WFAPI SDK is a collection of APIs allowing software developers and system administrators to access specific features of XenDesktop. It has been extended to add several new functions requested by the development community.

No doubt about it, with XenDesktop 4 the desktop virtualization revolution has begun! Find out more at

Derek Thorslund
Citrix Product Strategist, HDX

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