class in UnityEngine.NetworkingSwitch to Manual
Class defines network topology for host (socket opened by Networking.NetworkTransport.AddHost function). This topology defines: (1) how many connection with default config will be supported and (2) what will be special connections (connections with config different from default).
Example: p2p game with 10 people in the room and connection to chat server, in this case it will be 10 default connections and one special.
The NetworkServer and NetworkClient classed can be configured with a HostTopology instance.