An exchange capable of, when a failure occurs, preventing a service from deteriorating without requiring an operation performed by a user is provided. An exchange (1) includes a notification control unit (2) configured to, when the exchange enters an operating state, request a server apparatus to transmit a notification for making a predetermined application installed in a communication terminal registered in the server apparatus register the application in the exchange, and a terminal control unit (3) configured to register the predetermined application in the exchange.