Thank you for your quick answer.
The first player who joins, has the authority to kick and ban other player?
If it's so, i need to connect a dummy player after the server is created, to be safe.
//EDIT: Solved!
No, only authorized players are able to kick and ban. I'm a little out of it right now, but if I'm thinking straight I believe the host has no implicit power. You decide what the host has power over.
To expand, a list is kept on the server (SteamIDs, passwords, whatever you decide to use), and players must supply a correct value via TNManager.SetAdmin(string pass) in order to kick or ban others. The host doesn't have access to this list unless the host is also running the server (can we please rename "host" to "channel operator"
)
As Aren said, TNet isn't p2p, but it's important to note that the game server acts as a "smart relay". It has no concept of the game, the world, the physics, etc. It simply relays packets. That's not to detract from the genius of TNet, though. There is no "one size fits all" server-authoritative solution. A lot of TNet's worth, in my opinion, comes from how well-written and extensible it is. If you want your server to be authoritative, you can make it so with surprising ease.