How does the device connect to the server?

My device is a Socket connection using TCP, how to configure the server address?
Is this the case:

tcp://xxx.xxx.xxx.xxx:5001

Will the server automatically identify this port and use a valid protocol?

Each individual port corresponds to a different protocol, so there's no automatic identification, but it's also not needed because you're telling it which protocol to use by selecting the port.

That is, I find the corresponding port according to the protocol and can connect to the server correctly?
Because I test it with ios app now, and the protocol I see is: osmand 5055, the http protocol is configured on the app, and if the device sends the tcp protocol, it is configured as: tcp://xxx.xxx.xxx.xxx:port?

http://xxx.xxx.xxx.xxx:port for the app

on an tracking device ip : port