GATEWAY DEVICE

PROBLEM TO BE SOLVED: To attain high speed for a gateway device by reducing access to a memory when a reception frame is processed and transferred by the device. SOLUTION: A network interface part 1 converts a frame from a real network so as to output it onto a bus, a protocol processing part 3 executes the header processing of the frame which is outputted from the interface part 1, a delay part 5 outputs the frame after waiting for the portion of the processing time of the processing part 3 when the frame of the interface part 1 is received, a switch part 6 replaces a header part in the frame of the delay part with processing data of the processing part 3 after the frame of the delay part is inputted so as to store it in a memory 2 as a transmission frame and a data transfer part 4 reads the transmission frame of the memory 2 so as to transfer it.