There is provided a relay device which enables improved communication quality and cost-reduction, wherein the device carries out both real-time communications and non-real-time communications. A first communicator carries out packet communications with a first real-time communication device and a first non-real-time communication device, which are connected through an external network. A second communicator accommodates a second real-time communication device included in an internal network. A_third_communicator_accommodates_a second_non-real-time communication device included in the internal network. A connection_controller_controls_a_connection_of the_first_and_second real-time communication devices. A timing checker detects a timing before the connection between the first and second real-time communication_devices,_and_a_timing_after_the disconnection_between them by monitoring operations of the connection controller. A resource controller controls resources for real-time communications and those for non-real-time communications based on the timings detected by the timing checker.