Like most programs that work over the Internet, TeamViewer does not require any special settings for correct data transfer. A stable Internet connection is enough. However, there could be situations when traffic needs to be restricted to prevent unauthorized access. This is often done in various companies, especially large ones. In this case, some changes will have to be made to the firewall in order for TeamViewer to continue to work correctly.
The program can use three different ports: TCP / UDP 5938, TCP 443 and TCP 80. Note that the signal is transmitted only through one of them. There is a certain sequence of ports on which the program will work. If one port is not available, then an attempt will be made to transmit the signal on the next port in the sequence.
TCP/UDP – Port 5938
This port is a priority for TeamViewer. If it is not blocked in the firewall, then packets will always be transmitted through it. The main advantage of the port is its high speed.
As for mobile devices, they can only transmit a signal through this port. The only exceptions are iOS devices that can also work with TCP 80. If you cannot connect to TeamViewer on your mobile device, then you need to contact your mobile operator to unblock this port, or check your firewall or router settings.
TCP – port 443
Port 443 is next in priority. In addition to remote control of computers, TeamViewer updates are usually carried out through this port, as well as a number of other operations. It works a little slower than 5938, but is just as reliable.
TCP – port 80
If both previous ports are blocked, then port 80 comes into play. This option is considered the worst due to the fact that the connection speed is low here, because the port is used by many other applications and services. It is also unreliable, so the program will only work through it as a last resort. Another disadvantage of this option is the lack of automatic connection in the event that the connection was unexpectedly lost. Then you will have to reconnect manually. Out of mobile devices, only those under the iOS operating system can use this port.