Self-host your own RustDesk server, it is free and open source (A Teamviewer Alternativ)
Documentation : https://rustdesk.com/docs/en/self-host/install/
Public Key, you can be found it within /opt/RustDesk Server/id_ed25519.pub
user are forced to entern the key (by default) can be removed in startup script
By default, hbbs listens on 21115(tcp) and 21116(tcp/udp), 21118(tcp), hbbr listens on 21117(tcp), 21119(tcp). Be sure to open these ports in the firewall. Please note that 21116 should be enabled both for TCP and UDP. 21115 is used for NAT type test, 21116/UDP is used for ID registration and heartbeat service, 21116/TCP is used for TCP hole punching and connection service, 21117 is used for Relay services, 21118 and 21119 are used to support web clients. If you do not need web client (21118, 21119) support, the corresponding ports can be disabled.
TCP(21115, 21116, 21117, 21118, 21119)