| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique of protecting the man-in-the-middle attack without the need for a large amount of introduction cost.SOLUTION: There is provided a network monitoring device comprising: an address correspondence information storing part 11 configured to store address correspondence information indicating correspondence between a logic address and a physical address of each of a plurality of communication devices; an incorrect address response detection part 12 configured to detect an address response indicating a response to a solution request of the physical address to the logic address in a network in which the communication devices are connected, and determine that the address response is incorrect when a combination of the logic address of an initiating party and the physical address of the initiating party included in the detected address response is not stored in the address correspondence information storing part 11; and a recovered address response transmission part 13 configured to recover an incorrect address response by referring to the address correspondence information storage part 11, and transmit the recovered address response to a destination of the incorrect address response. |
