A server includes a database that stores template pairs for a plurality of persons, the template pairs each pairing a first template and a second template that are acquired by using first and second polarization methods different from each other, respectively, from a same person, and a collating unit that collates a third template by the first polarization method, the third template being transmitted from a terminal device, with the template pairs for the persons, collates a fourth template by the second polarization method, the fourth template being transmitted from another server, with the template pairs for the persons, and performs personal authentication according to whether a first template pair and a second template pair are an identical template pair, the first template pair including the first template that coincides with the third template, and the second template pair including the second template that coincides with the fourth template.
