A packet switch apparatus including a plurality of connecting points, each being coupled to one of a plurality of data processing units, and apparatus for receiving a first packet including identification information of a first data processing unit via a first connecting point. The invention further includes a storage for storing correspondence between the first data processing unit and the first connecting point based on the identification information. Apparatus, responsive to reception of a second packet from a second data processing unit to be transmitted to the first data processing unit, transmits the second packet to the first data processing unit via the first connecting point based on the correspondence stored in the storage.