A device (300s) has an authentication ID generator (320) for applying a first one-way function to a combination of a process password and information to be shared, and generating an authentication ID; an anonymizer (330) for generating anonymized information from the authentication ID and the information to be shared; an information sharing section (340) for causing the anonymized information to be held on another device; and an anonymized information process requesting section (350) for sending a process request containing the process password, and requesting the other device to subject the held anonymized information to a predetermined process, the request being sent on the basis of a match between the authentication ID of the anonymized information and the result of the first one-way function being applied to the combination of the process password and the anonymized information held on the other device.