Frequently Asked Questions

This section provides answers to general, frequently asked questions about the Zoom Workplace VDI app.

Optimization FAQ

The following sections provide answers to common questions regarding media optimization.

How does Screen Sharing work with VDI?

Screen sharing for VDI users is handled differently depending on whether the user is sharing their screen from a virtual desktop or receiving a share session from another participant while using a virtual desktop.

When another participant shares their screen during the meeting, the video from that participant is sent to the virtual desktop and, by default, is forwarded to the VDI Plug-In. If necessary, administrators can change behavior through the DisableShareOffload registry key.

Conversely, when a virtual desktop user shares their screen, the screen sharing video content is sent directly from the virtual desktop to the Zoom Cloud and distributed to all other meeting participants. If the Share Sound option is checked, the audio from the virtual desktop is forwarded to the VDI Plug-In, and is sent in a separate audio stream to the Zoom Cloud, marked for the share session. The Zoom Cloud then combines the video and audio streams and distributes the media to participants through the active screen sharing session.

Is local screen sharing processed on the VDI server?

Yes, initiating screen sharing from the virtual desktop requires the VDI server to process local and outbound screen sharing data. Since virtual desktops are provisioned with virtual CPU cores, some of the offloading to a GPU that can be done with real hardware is not an option for the virtual desktop. To address those performance challenges, the Zoom Workplace VDI app is optimized to reduce the frame rate of screen sharing to five frames per second to maintain server performance.

Customers can increase the default frame rate using the EnableOptimizeForVideo registry key. The actual frame rate that is achieved is dependent on the number of cores provisioned to the desktop and other factors, such as the media being shared and the application used to present the media.

For customers with concerns about virtual desktop performance, capture rates can be reduced using the ShareCaptureFps registry key to optimize server performance.

How is the out-of-band UDP connection established?

The out-of-band UDP connection is established between the Zoom Workplace VDI app and Plug-In using UDP ports 7200-17210 by default. This encrypted connection is confirmed through the already-encrypted virtual connection between the Zoom Workplace VDI app and Plug-In (e.g. the Citrix ICA or Horizon Blast channel). If the system fails to establish a UDP connection, it will failover to the virtual connection channel.

If necessary, Administrators can adjust the UDP port range using the UDPPortBegin and UDPPortEnd registry keys between the values of 1000-65000. The total range must be at least 100 ports, which means the lowest possible valid range is 1000–1100 and the highest possible range of 100 is 64000–64100 (the UDPPortBegin value cannot be higher than 64000).

Organizations that use the Windows Defender Firewall with customized port ranges require advanced configurations. Refer to the Windows Defender Firewall Considerations section for more information.

Heads Up

Zoom recommends reserving at least 8 ports per user if multiple users share the same host machine.

How does the virtual connection failover work?

In the event a direct or UDP connection cannot be established between the Zoom Workplace VDI app and Plug-In, the connection will fail over to the virtual connection used by the virtual desktop agent. These connections have limited bandwidth available and will likely impact media quality.

Can I force the UDP/Channel Optimized connection?

The VDI registry keys allow for enforcing various connection methods using the DisableMMRDirect, DisableICABridge, and DisableUDPBridge keys.

• DisableMMRDirect disables direct connections from the Plug-In to the meeting server, and automatically attempts UDP Optimized mode.

• DisableICABridge disables the virtual channel connection failover between the Plug-In and Zoom Workplace VDI app if a direct connection or UDP Bridge cannot be established. If no connection is established, Fallback Mode will be used. This key also disables the Horizon Blast channel.

• DisableUDPBridge disables the ability to form an out-of-band connection between the Plug-In and Zoom Workplace VDI app and force connection attempts to the virtual connection if a direct connection cannot be established. If no connection is established, Fallback Mode will be used.

How is VDI traffic protected?

All in-meeting traffic is secured with 256-bit AES-GCM encryption for UDP connections, regardless of optimization configuration. Failover media connection methods utilize TLS 1.2 encryption.

All communication between the Plug-In and Zoom Workplace VDI app is encrypted via the intrinsic virtual connection, or an out-of-band UDP connection.

What ports are required for using the Zoom Workplace VDI app?

No special networking configurations are required for meeting connectivity with the Zoom Workplace VDI app over the standard (i.e., non-VDI) app. Networking configuration rules are available in our firewall and proxy configuration guide.

Refer to the section on UDP Connection Establishment for port requirements for Direct and Channel Optimized modes.

I use the Windows Defender Firewall. Do I need to do anything?

The Zoom Workplace VDI app MSI package opens UDP ports 7200-17210 within the Windows Defender firewall during installation for Plug-In connectivity. Companies that utilize the Windows Defender firewall and customize the UDP port range using registry keys must update these parameters within the Windows Defender Firewall to maintain functionality.

General FAQ

Where are the latest VDI release notes?

You can find our latest VDI release notes here.

Does the Zoom Workplace VDI app require a persistent VDI environment?

The Zoom Workplace VDI app works in both persistent and non-persistent environments.

Can the VDI app run as a virtualized application?

As of the date of this document’s publication, the Zoom VDI Workplace app does not support being run as a virtualized application, but this option is being considered. If this feature is important to your business, please contact your Zoom account representative or support team for more information.

Does the VDI app support….?

The Zoom Workplace VDI app is on-par with the standard (i.e., non-VDI) Zoom Workplace desktop app in almost every way. This includes features such as optional end-to-end encryption, gallery view, speaker view, multi-speaker view, language interpretation, captions, breakout rooms, screen sharing, meeting wallpapers, Zoom AI Companion, Zoom Mesh, Zoom Clips, Zoom Docs, and more. Occasionally, due to a staggered release time between the standard Workplace desktop app and VDI app, there may be occasional feature disparity until a new VDI release is available.

Additionally, some VDI features are limited in use, which is elaborated in the VDI Feature Limitations section of this document. To see the list of VDI feature comparisons, please review our VDI app comparison article.