An electronic apparatus includes a communication unit connected to a first unit network and configured for communication with a plurality of unit networks comprising a plurality of clients, and a controller configured to control the electronic apparatus within the first unit network to operate in one of a proxy mode and a node mode if the plurality of clients form a private network, wherein the controller controls the electronic apparatus to directly communicate with a second unit network in the proxy mode, and controls the electronic apparatus to be connected to another client of the first unit network operating in the proxy mode and communicate with the second unit network through the other client in the node mode, and when the electronic apparatus operates in the node mode, the controller selectively changes the operational mode to the proxy mode depending on a private network service provided to the electronic apparatus.