| 摘要 |
PROBLEM TO BE SOLVED: To increase an operating speed of destination address retrieval of transfer data with a router of a LAN. SOLUTION: Each retrieval circuit consists of 32-bit registers. An address '12345600H' is registered as an address NA + SNA of a subnetwork in a registration data register 41, a subnet mask 'FFFFFF00H' is made initial setting and N addresses NA + SNA and their subnet masks are set in a mask register 51. An IP address '12345600H' of a retrieval data register 33 is inputted to comparators 61 to 6N, and the address of a registration data register 41 and the subnet mask of a mask register 51 are inputted to a comparator 61. The comparator 61 compares the value which masks the IP address through a subnet mask with an address from the register 41 and outputs 'coincidence' from an output 35. Because addresses of subnet masks are entirely different within the same LAN, comparators 62 to 6N of other registration data registers 42 to 4N outputs 'uncoincidence' from the output 35. |
