Information relay device, remote service system, information relay method, and non-transitory computer readable medium

A plant network entrance device includes a change information reception unit configured to receive change information for changing a control parameter of a plant facility from a change execution device, a change information transmission unit configured to transmit the change information to the plant facility, an operation data acquisition unit configured to acquire pre-change operation data that is operation data before a time at which a change in the control parameter based on the change information is made and post-change operation data that is operation data after the time at which the change is made, an improvement rate calculation unit configured to calculate an improvement rate for operation states before and after the change on the basis of the pre-change operation data and the post-change operation data, and an improvement rate transmission unit configured to transmit the improvement rate to the change execution device.