Patent ID: 8064466
Filing Date: 2011-11-22
Classification: H04L

Abstract:
1. A program, embodied in a non-transitory, tangible computer-readable storage medium, for causing a computer to monitor a specified area in a network divided in a plurality of areas, said program comprising: a first obtaining step of obtaining a value of an input packet counter from each of input candidate edge routers that are possible edge routers to receive a specified packet which is transmitted from a specified source address to a specified destination address, passing through a specified area, from a router within an adjacent area, of edge routers set in a boundary between the specified area and respective adjacent areas adjacent to the specified area, and of storing the values in a storing unit as a first input packet number; a test packet transmitting step of transmitting a test packet having a destination address of an output edge router that is an edge router which supplies the specified packet externally out of the specified area or a test packet having the specified destination address, to a source router connected to a network indicated by the specified source address for a predetermined number of times; a second obtaining step of obtaining a value of the input packet counter from each of the input candidate edge routers and storing the values in the storing unit as a second input packet number; and a specifying step of calculating a difference between the first input packet number and the second input packet number stored in the storing unit in every input candidate edge router and specifying an input edge router through which the specified packet is supposed to pass, from the input candidate edge routers, according to the calculated difference.