摘要 |
According to one embodiment, a communication system includes a first terminal to be connected to a first communication network, assigned a terminal ID and driven by power supplied from a battery, a server apparatus to be connected to a second communication network differing from the first network, to periodically confirm presences of the first terminal and a second terminal to be connected to the second communication network, and to communication-connect between the first and the second terminals in the case of presences thereof, and a controller which makes the server apparatus monitor that the first terminal is present on the first communication network by a second period longer than a first period monitoring that the second terminal is present on the second communication network. |