Design Decision: Citrix Virtual Desktops HDX Bandwidth Estimates
Overview
Citrix HDX is a broad set of technologies that provides end-users a high-definition experience for their hosted desktops, designed around the three technical principles of:
• Intelligent redirection
• Adaptive compression
• Data de-duplication
Citrix HDX decreases bandwidth consumption and optimizes the end-user experience. How much bandwidth is required for each user session is an age-old question and challenging to predict. How the user interacts with the desktop generates most of the traffic that determines the outcome of the end-user experience. Therefore, each user session with a virtual desktop is unique in its bandwidth requirements. Generally, the answer about the amount of bandwidth required for virtual desktop sessions is “it depends.” However, through user workload testing, we can monitor bandwidth consumption to provide updated estimated ranges. This testing will allow Citrix admins to assess the HDX bandwidth requirements for several typical workloads for Citrix DaaS sites.
Test Setup
The testing environment used Citrix Virtual Apps and Desktop Service (CVADS) delivered via Citrix Cloud for all tests. Using the evergreen CVADS environment ensures that the latest fixes and technologies are used for the overall end-user experience. The following is the additional information about the components used during testing:
• Citrix Gateway Service was used for all access to the test environment.
• HDX connections were made from a Windows 10 Endpoint with Citrix Workspace App 2109 for Windows installed.
• A Windows 10 virtual machine with Citrix VDA 2106 and Citrix Optimizer v2.8.0.143 hosted on Citrix Hypervisor 8.2.
• Default Citrix policies were applied for each test iteration.
Test Details
The amount of data required and used by Citrix HDX depends on the end user’s activity within the desktop. For example, a typical task worker who only uses Microsoft Office requires much less bandwidth than a user on Microsoft Teams video calls throughout the day. To provide any estimated multiple test scenarios must be run and reported. The details for each of the test scenarios run during the bandwidth testing are as follows.
Idle User
• The end-user is not actively working with the VDA. No active screen updates, keyboard or mouse movements are captured.
Microsoft Office
• The end-user works within Microsoft Word, Microsoft Excel, and Microsoft PowerPoint opening multiple documents, typing, copying/pasting graphics between documents, and switching between the files.
Web Browsing
• The end-user launches both Google Chrome and Microsoft Edge web browsers. A graphically rich website is used for this test.
Microsoft Teams Meeting (Workspace for Windows Microsoft Teams Optimization)
• The end-user joins a Microsoft Teams Meeting with both audio and video enabled. During the meeting, the organizer shared a PowerPoint presentation along with their video. The Teams meeting test ran for 10 minutes.
YouTube Video Playback
• The end-user is watching a 1080p resolution, 30 FPS YouTube video movie trailer that lasts two minutes and thirty seconds. Two separate tests were performed, one with Browser Content Redirection (BCR) enabled, the other with BCR disabled.
Results
The following table provides the results of the average bandwidth captured for each of the testing scenarios.
| Idle (kbps) | MS Office (kbps) | Web Browsing (kbps) | MS Teams Meeting (kbps) | YouTube 1080p - BCR Enabled (kbps)) | YouTube 1080p - BCR Disabled (kbps) |
|---|---|---|---|---|---|
| 0.32 | 22.14 | 478.38 | 5.78 | 0.49 | 1663.47 |
The following table provides the average of the minimum and maximum average range captured each of the test scenarios.
| Idle (kbps) | MS Office (kbps) | Web Browsing (kbps) | MS Teams Meeting (kbps) | YouTube 1080p - BCR Enabled (kbps)) | YouTube 1080p - BCR Disabled (kbps) |
|---|---|---|---|---|---|
| 0.02–1.27 | 0.40–46.30 | 213.93–758.16 | 4.51–43.22 | 0.04–1.97 | 1528.03–2252.53 |
Key Takeaways
Citrix continues to improve the HDX protocol to apply optimizations based on the end-user working scenarios intelligently. Each improvement brings further reductions in overall bandwidth consumption utilization to Citrix environments. Citrix bandwidth consumption depends on the use case, so there is no right or wrong answer on bandwidth consumed per session. However, we can offer bandwidth estimates to assist you with the bandwidth requirements for any virtual desktop project by continually testing different scenarios. Citrix HDX continues to provide a high-definition user experience for the typical workload scenario by default. Enabling the Citrix Microsoft Teams and Browser Content Redirection (BCR) optimizations decrease session bandwidth further, ensuring a great end-user experience.