Estimation of router that is cause of silent failures

A router estimation system, comprising one or more processors, the router estimation system causing at least one of the one or more processors to execute:

• a router group data storing process of storing, for each one of a plurality of network slices constructed in a communication system, router group data indicating a group of routers that form the each one of the plurality of network slices;
• a correlation decrease degree calculation process of calculating a degree of correlation decrease, the degree of correlation decrease being linked to a pair of one slice communication which is a slice communication held by one of function elements included in the communication system with use of one of the plurality of network slices and another slice communication which is held by one of the function elements included in the communication system with use of one of the plurality of network slices and which is other than the one slice communication, the degree of correlation decrease being a degree of decrease in strength of correlation between a performance index value that indicates performance of the one of the function elements that holds the one slice communication in the one slice communication and a performance index value that indicates performance of the one of the function elements that holds the another slice communication in the another slice communication;
• a decrease determination process of determining, for each of a plurality of pairs which are each the pair of the one slice communication and the another slice communication, whether the degree of correlation decrease linked to the each of the plurality of the pairs satisfies a given decrease determination condition;
• a pair count identification process of identifying, for each one of a plurality of slice communications held in the communication system, the number of pairs that are each the pair of the one slice communication and the another slice communication one of which is the each one of the plurality of slice communications, and that are each linked to the degree of correlation decrease satisfying the given decrease determination condition;
• and
• a router estimation process of estimating at least one router as a router that is a cause of deterioration of performance of the function elements related to the each one of the plurality of slice communications, the at least one router being included in a group of routers which are identified based on the router group data and which are located on a route of the each one of the plurality of slice communications for which the number of the pairs that satisfies a given pair count condition is identified.