How does servers at tournaments work ?
A local area network (LAN) is a collection of devices connected together in one physical location, such as a building, office, or home. A LAN can be small or large, ranging from a home network with one user to an enterprise network with thousands of users and devices in an office or school.
but basically, theres a server running there specifically just for the tournament and only the pc's at the tourney are connected to it