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Azure Virtual Desktop Blog
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Announcing public preview of symmetric NAT support for RDP Shortpath

Rinku_Dalwani's avatar
Rinku_Dalwani
Icon for Microsoft rankMicrosoft
Feb 07, 2023

We are pleased to announce the public preview of symmetric NAT support for RDP Shortpath. This feature is the extension of the GA RDP Shortpath feature that allows us to establish a UDP connection indirectly using relay with the TURN (Traversal Using Relays around NAT) protocol for symmetric NAT.

What is TURN?

TURN is a popular standard for device-to-device networking that is now available for low latency, high-throughput data transmission with Azure Communication Services. It allows developers to quickly bootstrap to a high-performance, redundant, and globally scaled set of networking services that are often themselves complex and expensive to deploy. These services can power real-time communication between web or mobile applications built with open-source WebRTC clients, even when endpoints are behind NAT or firewalls that may prevent direct peer-to-peer connections. Developers can use the low-level standards-compliant TURN service for raw high-performance data transmission or layer voice or video communication experiences on top of this data channel. 

 

How can I use it?
The feature is available in validation host pools and enabled for all connections. There is no additional configuration needed to enable the feature.

Since outbound connectivity is required between the session hosts and client to function as intended, we recommend allowing outbound UDP connectivity to the Internet. IT Admins can limit the port range used to listen to the incoming UDP flow.

The feature is currently available in 14 regions, and we are planning to extend it to other regions in the future. The connection initiated across regions will use UDP established through TURN where available. Otherwise, the connection will revert to the existing mechanism.

 

To learn more about the feature and configuration details, please check out Azure Virtual Desktop RDP Shortpath for public networks.

 

Further reading resources:

 

Updated Feb 09, 2023
Version 2.0
  • gacpac's avatar
    gacpac
    Copper Contributor

    any update for when it will be in production for symmetric NAT?

  • gacpac's avatar
    gacpac
    Copper Contributor

    will you be able to pick between STUN and TURN over symmetric NAT or for now only TURN?

  • gacpac's avatar
    gacpac
    Copper Contributor

    Any update on when is going to be out of preview?

  • gacpac 

    Thank you for reaching out to us. I wanted to let you know that we are currently analyzing the preview data. Once we have completed our analysis, we will announce when we will go GA. Thank you for your patience and understanding as we work to provide the best possible results.
  • gacpac UDP-based transport offers better connection reliability and more consistent latency. With STUN you can get direct connection between client and session host. However, if there a firewall or NAT device blocking a direct UDP connection, then an indirect UDP connection can be relayed using TURN between the client device and the session host over a public network. Here is the link for more details.