To host a multiplayer game you must start a dedicated server, using the launcher shortcut on your desktop. The server will run even if you are not connected to it, allowing you to host games for your friends even if you are not around. The server window displays usefull information for those interested, like the number of people currently playing, the ip of each connected player and how much bandwith the server is actually using. To stop the server at any time just close it's window. The server also registers itself with the master server, which will provide it's name to all those who are looking for a game to connect to.