MOBILE TERMINAL, MUTUAL AUTHENTICATION SYSTEM, MOBILE TERMINAL CONTROL METHOD AND MOBILE TERMINAL CONTROL PROGRAM

摘要

It is an object to provide a mobile terminal, a mutual authentication system, a mobile terminal control method and a mobile terminal control program which can improve convenience by automatically making a security function valid again under certain conditions from a state in which the security function becomes temporally invalid due to user's operation. A mobile phone (20) has a first state in which user's operation for a operation key (24) becomes valid in the case that mutual authentication is completed with an authentication key (30), a second state in which user's operation for the operation key (24) becomes invalid in the case that mutual authentication is not completed with the authentication key, and a third state in which user's operation for the operation key (24) becomes valid in the case that a predetermined release operation is carried out in the second state. When mutual authentication is completed in the third state, the mobile phone moves to the first state.