According to an aspect of the embodiment, an input/output device transmits a message to a first node controller of a parent node which is set in advance via a cross bar. At this point, the cross bar generates information based on node information of the input/output device, and adds the generated information to the message. The first node controller transmits, via the cross bar, the message to a second node controller of a parent node corresponding to an input/output device that is to receive the message. The second node controller transmits, via the cross bar, the message to an input/output device that is to receive the message. At this point, the cross bar transmits the message restored by deleting the generated information from the message to the input/output device which is set as a destination.