Contactless IC card, responding method, and program therefor

摘要

Provision of a high-grade random number by means of a simple configuration enables to provide a contactless IC card, a responding method, and a program therefore; those can control the collision of the initial responses in minimum. The contactless IC card, the responding method and the program comprise the provisional random number generating means for generating a provisional random number according to a part of operations to be used for the generation of a random number, the provisional random number storage means for storing the provisional random number generated by the provisional random number storage means, and the random number generating means for generating a random number on the basis of the provisional random number at receiving the request from the reader/writer.