A packet processor transfers a message received by a first (second) port to a second (first) port. When first specific information is included in the received message, a QoS terminal detector detects a communication terminal, which is a sender of the message received by the first port or a destination of the message received by the second port, as a QoS terminal requesting application of QoS. When the QoS terminal does not satisfy a preset connection condition associated with the QoS terminal connectable to the first port via a first network, an output unit outputs information indicating that the connection condition is not satisfied.