The RD Gateway can be used to securely publish RemoteApps or Full Desktops over the internet over Secure Sockets Layer (SSL). RD Gateway in Windows Server 2012 takes advantage of enhancements
to the RDP protocol, including the new RDP Wan Transport feature. RD Gateway in Windows Server 2012 now supports real time traffic over high latency networks by adding support for connections using UDP. If the client or endpoint does not support UDP, the RD Gateway in
Windows Server 2012 will fall back to using HTTP. The support for UDP in Windows Server 2012 is enabled by default but can be disabled if needed. This wiki shows the changes that can be performed on the UDP settings of the RD Gateway
With Windows Server 2012, many of the RDS roles can now be managed using the new central Server Manager console. The RD Gateway is an exception to this. So we open up the Remote Desktop Gateway Manager which is also available as a Windows 8 tile.
We right-click the properties of the RD Gateway server and select properties and on the properties dialog we select Transport Settings.
Here we have the option to disable UDP support, we also have the option to change the default port it uses (3391). If we change any of the settings we need to confirm that the following
actions will be performed; 1. A listener is added to the firewall, all active connections will be disconnected and the RD Gateway Server will be restarted.
Note that when UDP is enabled and the client supports it, this will also show up in the monitoring screen of the RD Gateway management console.