Abstract: A stranger who has come across user information of a user is prevented from being successfully authenticated as the user. A user authentication system includes: an authentication information acquisition unit (20) configured to obtain an entered password of a user; a user authentication unit (22) configured to execute authentication of the user based on the entered password; and an authentication procedure change unit (28) configured to change, when the authentication of the user fails and the entered password matches or is similar to a password candidate that is based on information associated with the user, a procedure of the authentication of the user which is executed by the user authentication unit (22), based on whether or not a genuine password of the user matches or is similar to the password candidate.

Abstract: A stranger who has come across user information of a user is prevented from being successfully authenticated as the user. A user authentication system includes: an authentication information acquisition unit (20) configured to obtain an entered password of a user; a user authentication unit (22) configured to execute authentication of the user based on the entered password; and an authentication procedure change unit (28) configured to change, when the authentication of the user fails and the entered password matches or is similar to a password candidate that is based on information associated with the user, a procedure of the authentication of the user which is executed by the user authentication unit (22), based on whether or not a genuine password of the user matches or is similar to the password candidate.

Abstract: An information processing device according to one embodiment includes an acquisition unit, an estimation unit, and a transmitting unit. The acquisition unit acquires, in response to an information provision request from a user terminal to an information providing means that provides facility information, the number of accesses to a facility since a specified period before receipt of the information provision request. The estimation unit estimates whether a facility can accept reservations based on seating capacity of the facility and the number of accesses to the facility. The transmitting unit outputs information based on an estimation result by the estimation unit to the user terminal.

Abstract: Vacant seat information for specifying the number of vacant seats in a store and store identification information for identifying the store are acquired from a mobile terminal device of a user of the store. The vacant seat information is registered in a storage in association with the store identification information. A search condition including the number of members is acquired from a terminal device of a user who looks for a target store to use. The vacant seat information and the store identification information registered in the storage are collated with the acquired search condition. The collation results are transmitted to the terminal device.

Abstract: Vacancy information indicating the number of vacancies which is counted in units of using-persons in a facility that is occupied by persons who use an establishment is stored in a vacancy information storage unit. An information processing apparatus acquires the number of using-persons which is specified by a user. The information processing apparatus searches, on the basis of the vacancy information stored in the vacancy information storage unit, for establishments that can be used by persons of which the number is acquired. At this time, the information processing apparatus includes an establishment, in establishments that can be used, where the degree by which the number of using-persons exceeds the number of vacancies indicated by the vacancy information is smaller than or equal to a reference value. The information processing apparatus causes the found establishments to be presented.