This article describes how to configure the SmartRendering Bandwidth Threshold for HDX MediaStream Windows Media Redirection.

Background

XenDesktop 4 enhances SmartRendering for HDX MediaStream. In addition to automated fallback to server-side rendering when the client does not have the necessary codec, XenDesktop 4 adds such fallback when the effective network bandwidth is below a specified threshold. This helps to overcome limitations in the performance of HDX MediaStream when bandwidth is too low or latency is too high for client-side rendering.

In general, HDX MediaStream Windows Media Redirection requires enough bandwidth to accommodate the bit rate of the videos to be viewed. The SmartRendering bandwidth threshold determines the effective bandwidth below which HDX MediaStream must revert to server-rendered multimedia delivery to ensure the best possible user experience. Effective bandwidth takes into account the impact of latency, ensuring a more accurate SmartRendering decision.

 
In XenDesktop 4, the default bandwidth threshold is 0.5 Megabits per second (Mbps). This might be too low if the users watch videos with higher bit rates. It is definitely too low if the users watch High Definition videos (720p). It might be necessary to increase this threshold to several Megabits according to the types of videos that must be delivered.
 
On the other hand, if the user experience provided by Windows Media Redirection is preferred even when effective bandwidth is low, then this threshold can be set to 0 (zero) to force client-side rendering regardless of bandwidth.

 

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Instructions

Caution! Refer to the Disclaimer at the end of this article before using Registry Editor.

To Configure the SmartRendering Bandwidth Threshold, set  the bandwidth threshold (in kilobits per second) on the Virtual Desktop Agent (VDA) in the following registry key:

[HKLM\SOFTWARE\Citrix\HdxMediastream\MinimumBandwidth]

On 64-bit platforms, the registry path is [HKLM\SOFTWARE\Wow6432Node\Citrix\HdxMediastream\MinimumBandwidth].

Caution! Using Registry Editor incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

This article describes how to configure the SmartRendering Bandwidth Threshold for HDX MediaStream Windows Media Redirection.

It is not required to restart the VDA. Once the registry key is updated, it takes effect from the next time the media player is started. The user must re-start the player or the application.

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