IP ADDRESS DUPLICATION MONITORING APPARATUS, IP ADDRESS DUPLICATION MONITORING METHOD, AND IP ADDRESS DUPLICATION MONITORING PROGRAM

摘要

An LAN is connected to a network outside the LAN via a router including an ARP cache holding for a predetermined period of time a pair of an IP address and a lower layer address which is an address lower than the IP layer and an apparatus to be monitored which provides service to the network exists in the LAN. An IP address duplication monitoring apparatus monitors IP address duplication for the apparatus to be monitored which is connected via the router and the network and includes a service requesting issuing unit for transmitting a plurality of service requests to an apparatus to be monitored, a service response analysis unit for receiving a service response obtained as a result of a service request, and a monitoring unit for instructing a service request to the service request issuing unit at a predetermined time interval, comparing a plurality of service responses obtained from the service response analysis unit, and judging whether an IP address duplication is present according to the comparison result.