COMMUNICATION DEVICE, COMMUNICATION SYSTEM, CONTROL METHOD FOR SAID DEVICE AND SYSTEM, AND PROGRAM FOR COMPUTER EXECUTION OF SAID METHOD

摘要

The invention prevents interruption of distribution of display information. If a connection has been established with a server that distributes display information to be displayed on a display device in synchronization with playback of content, a message processing unit processes a message from the server, said message being for controlling the distribution and being processed in accordance with a first protocol. In accordance with a second protocol, a connection checking unit checks whether the connection has been established. If the connection has not been established, in accordance with the second protocol, a connection request unit makes a request to the server to establish the connection.