Communication device, a communication system and a communication method

A communication apparatus comprising: a storage unit, related to the assigned tags and the packet source address of the packet, and stores them as entries; receiving means for receiving a packet from a network; learning unit, determining whether the memory cell exists in the received packet corresponding entry, and the absence of a case where the received packet is an entry corresponding to the assigned in the storage unit the source address stores the received packet tag and the received packet in the storage unit; and a processing unit, is present in the storage unit and When receiving an entry corresponding to the packet, the received packet to the address assigned corresponding to the received packet.