Frame conversion device

PROBLEM TO BE SOLVED: To obtain the high speed frame converter where the total number of gates in a storage circuit is small. SOLUTION: This frame converter includes a BUSIF2, that receives a frame of a fiber distributed digital interface(FFDI) form, an option field reconfiguration section 10 that connects to the BUSIF2 to convert an IP header of a frame of the FDDI form into an Ethernet(R) form, a check sum calculation section 12, an IPHRAM 8 that stores the IP header, a canonical conversion section 20 that converts a MAC address of a frame of the FDDI form into the Ethernet form, a MACRAM 22 that stores the MAC address after the conversion, and intermediate registers 38, 40 connected in series to convert a data part of the frame of the FDDI form into the Ethernet form. Each section is executed in parallel, and the conversion processing of each part of the frame of the FDDI form is executed in parallel.