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Citrix Workspace™ app for ChromeOS
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HDX Transport

April 23, 2026
Contributed by: 
C N

HDX adaptive throughput

Starting with the 2408 version, HDX adaptive throughput is supported. This feature intelligently fine-tunes the peak throughput of the ICA® session by adjusting output buffers. The number of output buffers is initially set at a high value. This high value allows data to be transmitted to the client more quickly and efficiently, especially in high-latency networks.

This feature provides better interactivity, faster file transfers, smoother video playback, and a higher frame rate and resolution resulting in an enhanced user experience.

Session interactivity is constantly measured to determine whether any data streams within the ICA session adversely affect interactivity. If that occurs, the throughput is decreased to reduce the impact of the large data stream on the session and allow interactivity to recover.

Note:

This feature is enabled by default.

Adaptive transport (EDT)

Adaptive Transport is a mechanism in Citrix Virtual Apps and Desktops™ that allows establishing connections for HDX sessions using a preferred transport protocol while providing a fallback to TCP if connectivity with the preferred protocol is unavailable.

The following transport protocols are supported:

Note:

This feature is enabled by default.

For more information, see the Adaptive transport section in the Citrix Virtual Apps and Desktops documentation.

How it works

When Adaptive Transport is set to Preferred, the client attempts to connect to the session with both the preferred protocol and TCP in parallel. This allows optimizing the connection time if it’s not possible to connect with the preferred protocol and the client must fall back to using TCP. If the connection is established using TCP, the client attempts to connect with the preferred protocol in the background every five minutes.

When Adaptive Transport is set to Diagnostic mode, the client connects to the session only with the preferred protocol. If the client is unable to establish a connection using the preferred protocol, it doesn’t fall back to using TCP, and the connection fails.

When Adaptive Transport is set to Off, Adaptive Transport is disabled, and the client connects to the session using TCP only.

EDT block diagram

Requirements

The following are the requirements for using Adaptive transport:

VDA System requirements

  • Virtual Delivery Agent

    ◈ Windows: currently supported version (2402 or later is recommended)

For more information, see System requirements in the Citrix Virtual Apps and Desktops documentation.

VDA Network requirements

Enable the Firewall in your internal and external network. For more information, see Network requirements in the Citrix Virtual Apps and Desktops documentation.

Gateway requirements

Citrix NetScaler® Gateway

  • 14.1.12.30 or later (recommended)
  • 13.1.17.42 or later (13.1.52.19 or later is recommended)

For more information, see Citrix Gateway.

On-prem Citrix Gateway

For more information, see HDX enlightened data transport support in the NetScaler Gateway documentation.

Citrix Gateway service

For more information, see HDX adaptive transport with EDT support for Citrix Gateway Service in the Citrix Gateway Service documentation.

ChromeOS requirement

  • The recommended Chromium version required is >=135 and later.
  • EDT feature must be in enabled state. Note: By default, this feature is enabled.

  • Network:

    ◈ If the gateway or non-gateway with SSL VDA is used, enable the UDP Port 443 in the firewall of the client-side network.

    ◈ If non-gateway and non-SSL VDA are used, enable the UDP ports 2598 and 1494 in the firewall of the client-side network.

Enlightened Data Transport

Adaptive transport delivers a superior user experience on challenging long-haul connections while maintaining server scalability. This feature delivers a high-quality HDX experience on web-based platforms.

How to configure

This feature is enabled by default. You can disable the adaptive transport feature in one of the following ways:

  • Google Admin Policy
  • Global App Configuration service

Google Admin Policy

For managed devices and users, administrators can disable the feature using the Google Admin Policy as follows:

  1. Sign in to the Google Admin Policy.
  2. Go to Device management > Chrome Management > User Settings.

  3. Add the following strings to the policy.txt file under the engine_settings key. You can apply this configuration to the following:

    Notes:

    You can apply this configuration on the following as well:

    • Device > Chrome > Apps and extensions > Users and browsers > Search for the extension > Policy for extensions.
    • Device > Chrome > Apps and extensions > Kiosks > Search for the extension > Policy for extensions.
    • Device > Chrome > Apps and extensions > Managed guest sessions > Search for the extension > Policy for extensions.

    The following is an example of JSON data:

    {
"settings": {
"Value": {
    "settings_version": "1.0",
            "engine_settings": {
                "features": {
                    "edt": {
                        "enabled": false
                            }
                        }
                    }
                }
            }
}   
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  4. Save the changes.

Global App Configuration Service

Administrators can disable the feature by navigating to Workspace Configuration > App Configuration > Session Experience > Connectivity > Adaptive Transport. Clear the checkbox and respective toggle button to disable the feature.

Verification steps

To check the connection over EDT or TCP:

  1. Open the command prompt in the Citrix VDA session.
  2. Run ctxSession -v.

  3. You can identify the output for adaptive transport EDT as follows:

    • If you use SSL VDA, then follow UDP->DTLS->CGP->ICA.
    • If you use non-SSL VDA, then follow UDP->CGP->ICA.

    EDT

Debugging and collecting Logs

In case if the adaptive transport feature isn’t working:

  • Collect Citrix Workspace app for ChromeOS logs. For more information, see Client logs.

  • When facing a connection issue with adaptive transport, test its functionality on the Citrix Workspace™ app for Windows or Mac with the same network, store URL, and user details. Testing with other Citrix Workspace app clients might help you to identify and eliminate any potential configuration or network-related issues.

  • Network Traces - Collect Gateway logs.

  • CDF traces on VDA side - Collect Citrix Diagnostic Facility (CDF) trace at system startup.

Loss tolerant mode for audio

Starting with the 2509 release, Citrix Workspace app uses loss tolerant mode for audio redirection. This feature improves the user experience by maintaining clear audio quality for real-time streaming when users are connecting through networks with high latency and packet loss.

Notes:

  • This feature is applicable to both app and desktop sessions.
  • This feature is enabled by default.

Prerequisites

  • Use VDA version - 2503.

  • Enable Loss Tolerant Mode for Audio. For more information, see Audio features in the Citrix Virtual Apps and Desktops™ documentation.

  • Enable HDX Adaptive Transport(EDT). For more information, see Adaptive Transport.

  • Enable Adaptive Audio (default:enabled). For more information, see Adaptive audio.

  • (Optional) For direct connections between Citrix Workspace app and VDA, enabling DTLS on VDAs is required.

  • (Optional) For remote connections, loss tolerant mode must also be supported on the Citrix Gateway Service or NetScaler Gateway.

Use case

This feature enhances audio quality for speech-focused microphone use cases, such as audio transcription, ensuring clearer and more accurate communication.

How to configure

Loss tolerant mode for audio is enabled by default. If disabled or to re-enable, complete the following steps:

  1. Enable HDX adaptive transport (EDT)
  2. Enable loss tolerant mode for audio.

Loss tolerant mode for graphics

Starting with version 2603, Citrix Workspace app for ChromeOS supports loss tolerant mode for graphics in Citrix sessions. This feature improves the video experience, particularly when you use poor network conditions with high packet loss and latency. The feature helps maintain session interactivity and prevents degraded user experiences characterized by lag and visual stuttering.

For more information, see EDT loss tolerant mode introduction in the Citrix Virtual Apps and Desktops documentation.

Note:

This feature is disabled by default.

About this feature

This feature delivers significant improvements to graphics performance with the following key benefits:

  • Enhanced network resilience: The application handles video and graphics effectively even when network connections experience challenges.
  • Improved remote work experience: Users working remotely or in areas with unreliable networks can use graphics-heavy applications without major performance issues like lag or pixelation.
  • Maintained productivity: The feature ensures consistent application performance, which maintains user satisfaction and productivity levels.
  • Optimized for challenging conditions: The enhancement performs better in networks with high packet loss and latency, delivering more stable graphics rendering.

System requirements

To use this feature, ensure that your environment meets the following requirements:

  • Citrix Virtual Delivery Agent (VDA) version 2311 or later
  • HDX Adaptive Transport (EDT) policy enabled
  • Loss tolerant mode for graphics policy enabled on the VDA
  • Minimum bandwidth of 30 Mbps (required for CVAD 2507 and later)

If you connect via the Citrix Gateway Service, you must also enable loss tolerant mode for graphics on the Gateway.

For more information about system requirements, see Loss tolerant mode system requirements in Citrix Virtual Apps and Desktops documentation.

Known limitations in the feature

  • When Loss Tolerant Mode is enabled, sessions might not reconnect after network disruption, which can result in session failure. [HDX-101830]

  • When Loss Tolerant Mode is enabled, session performance might degrade when available network bandwidth changes. The output bandwidth metric in Director > Session Performance dashboard might not accurately reflect actual bandwidth usage. [HDX-99338]

    For more information, see Session performance troubleshooting in Citrix Virtual Apps and Desktops documentation.

  • This feature does not support sessions when you enable the Secure ICA policy.
  • This feature does not support Kiosk mode.

How to configure

For managed devices and users, administrators can enable this feature using the Google Admin Policy as follows:

  1. Sign in to the Google Admin Policy.
  2. Go to Device management > Chrome Management > User Settings.

  3. Add the following strings to the policy.txt file under the engine_settings key.

    The following is an example of JSON data:

{
    "settings": {
        "Value": {
            "settings_version": "1.0",
            "engine_settings": {
                "graphics": {
                    "enableLossTolerantGraphics": true
                }
            }
        }
    }
}
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For more information about configuring loss tolerant mode, see How to configure loss tolerant mode in the Citrix Virtual Apps and Desktops documentation.

HDX Transport
April 23, 2026
Contributed by: 
C N
April 23, 2026
Contributed by: 
C N

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