Some noob questions about networking

Okay, I'm slightly new to this whole networking thing so I have a few questions:

Are the master servers handling everything, or is the server software doing it? I assume the master servers don't handle everything but I want to confirm it.

If you set up lots of servers for the same game (Like in minecraft) can you set up a master server for each server?

With the photon server can you set up your own servers, or do you have to buy cloud space from them?


Also this is more a broad question:

Can you give me some idea of how server software works so you can handle things serverside to prevent hackers?

Thanks for your time!

 

In regards to your last question I highly recommend reading some or all of these:
Valve Design/Optimization
Fast Paced Multiplayer Info(Cheating/Lag/Etc)
What every programmer neads to know about networking

 

Unity Master Servers are handling only the lists with connected machines, allocating IDs for. There IDs you can use on the Unity project for game logic.
The Unity project, game itself, is a completely separated things. It just send and receive requests to the Master Severs letting to know who are connected/disconnected and so.
You can set up lots of Master Servers for the same game. The only difference in the game code is the value of the variable named MasterServer.ipAddress. You have to compile the game with different values for this variable.
Game server mean the Unity project build with Network.InitializeServer() method called.
You have to care about the security things in your game code. You can use an authoritative or semi-authoritative game server for this, meaning to write the code on a way that clients are not doing all they want but doing actions under game server supervision.

 

For some reason the server supervision seems like a complicated and daunting task to me, I'm sure it's easy though.