Patent ID: 8826379

Claim:
An access control system comprising a first network, a second network lower in security than said first network, a communication terminal connectable to said first network and said second network, and a server which is connected to said first network and said second network, transmits collation information which is information generated from data and identifies the data to said communication terminal via one of said first network and said second network, and transmits the data to said communication terminal via another one of said first network and said second network, said communication terminal comprising: a communication control unit that acquires, from the server via one of the first network and the second network, the collation information, and acquires the data from the server via another one of the first network and the second network; a collation unit that collates the collation information and the data which are acquired by the communication control unit; and a reliability information DB construction unit that constructs, based on a collation result of said collation unit, a reliability information DB as a database of information indicating reliability of access to a resource.