Remote Desktop Protocol - Wikipedia

3389 port tcp or udp Actually, Remote Desktop requires TCP port 3389 to be open. Also, opening UDP port 3389 enables acceleration since RDP 8.0 (e.g. Windows 7 with RDP 8 Update, Windows 8, or Windows 10). In other words, if you use the former version of RDP (before RDP 8.0), then TCP will be the only protocol that can be used..

3389 port number used for  What’s the difference between Port 3389 and Port 22? Port 3389 is for RDP, focusing on remote access, while Port 22 is used for SSH, prioritizing secure shell access for command-line interactions.

port 33890  Likewise, what is port 3389 commonly used for? Port 3389 Basics TCP Port 3389 is used for the Windows Remote Desktop Protocol (RDP) and is also sometimes used by Windows Terminal Server. You may choose to allow or open this port in Windows Firewall to give another computer, either on the same network or another network, access to your computer.