PURPOSE: To obtain a communication system capapble of coping flexibly with PE address change and reaching quickly a destination PE by increasing/decreasing a counter value at a relative location information increase/decrease section, and transmitting the value to a next processing element (PE) from a transmission section together with a data.

CONSTITUTION: The case that a data is desired to be transmitted from a PE0 to other PE is considered. Assuming that each PE is combined at its nearest position. The relative position of other PEs is obtained around the PE0 and used as relative position information. The relative position information in the X direction is given by a counter 21 and the relative position information in the Y direction is fed by a counter 22. The packet has the counters 21, 22 as a header in place of an address of the destination PE. Thus, the PE receiving a packet where the counters 21 and 22 are both zero allows to process the packet in the own PE. On the other hand, if any of the counters is not zero, a transmission direction deciding section decides the transmission direction to which adjacent PE the packet is to be transmitted.