Well, depends on what platform you’re using, and what protocol you’re using.
The ‘raw’ socket blueprints use either TCP or websocket depending on what platform it is being used on. HTML5 uses websockets, everything else uses TCP.
The ‘normal’ socket blueprints use the Low Entry protocol, which requires you to use the Java library to create your server with. With that protocol, every platform (including HTML5) will be able to communicate with the server.
It is recommended to use the Java library to create your server with, unless you have very specific technical demands, in that case you’ll have to basically create your own protocol that deals with all of this.
The Java library can be download here: http://public…com/files/LowEntryUE4/java
The tutorial on how to use the library (in case you’re new to Java) can be found here: https://tutorials…com/getti…-with-eclipse/
I hope that helps.