| 摘要 |
<p>PROBLEM TO BE SOLVED: To solve the problem that when an appliance device is installed with a constitution where two lines at an LAN side and WAN side are drawn out of one router/switch, packets from the same IP may arrive from both two lines due to the setting mistake of the router or switch, resulting in the occurrence of a failure in the appliance device or the stop of communication caused by the occurrence of a failure in a network.SOLUTION: A monitoring device for monitoring communication flowing in four lines, that is, an LAN side line and a WAN side line of an appliance device and an LAN connection line and a WAN connection line for the appliance drawn out of a router/switch is configured to determine the matching of a communication session and a reception packet or the matching of mutual communication sessions, and to change the policy of the passage/disposal or routing of each communication session in accordance with the matching such that it is possible to continue or stop a communication service or an appliance service for each communication session.</p> |
