Patent 11108738 was granted and assigned to Alaxala Networks on August, 2021 by the United States Patent and Trademark Office.
A whitelist generation possibility/impossibility determination unit transmits a signal for permitting generation of a whitelist to a whitelist generating unit, in a case where an IP address corresponding to a source MAC address stored in a protocol information table matches the extracted source IP address, and in a case where an IP address corresponding to a destination MAC address stored in the protocol information table matches the extracted destination IP address.