I'm working on a real-time game engine and need to create a master server application to maintain a list of all active servers, however I'm not sure which network protocol to use.
The engine itself uses a combination of TCP and UDP.
I'm not sure how much of an overhead TCP has in comparison to UDP when running idle and packages only have to be send every couple of minutes at most, so I'm currently leaning towards using UDP.
However, obviously I need to make sure that all servers actually support UDP and TCP, so to do that, I would need both for the master server as well.
How is this usually done? What else do I have to take into account? Would it even make a mentionable difference?