Patent ID: 7747491
Filing Date: 2010-06-29
Classification: G06F,G06Q,G16H

Abstract:
1. An anonymous information system that performs anonymity conversion processing on original individual specifying information D that specifies an individual, to generate anonymous individual specifying information E, the anonymous information system comprising: a conversion splitting device configured to generate a first parameter KA and a second parameter KB based on a base parameter, the anonymity conversion processing being split into two portions to generate first conversion processing that is one of the two portions and second conversion processing that is the other one of the two portions, the first parameter KA being utilized for the first conversion processing and the second parameter KB being utilized for the second conversion processing; a first converting device configured to receive from said conversion splitting device the first parameter KA, to perform the first conversion processing on the original individual specifying information using a parameter P and the received first parameter KA according to a first expression, and to generate semi-anonymous individual specifying information, the first expression being represented as, a second converting device configured to receive from said conversion splitting device the second parameter KB, to receive from said first converting device the generated semi-anonymous individual specifying information C and to perform the second conversion processing on the received semi-anonymous individual specifying information C using the parameter P and the received second parameter KB according to a second expression, and to generate the anonymous individual specifying information E from the generated semi-anonymous individual specifying information C, the second expression being represented as, wherein said first converting device comprises an information providing device that provides the original individual specifying information D, and provides individual related information relating to the individual, said second converting device comprises an information storing device that stores the anonymous individual specifying information E, and stores the anonymous individual specifying information E in correspondence with the individual related information, and the conversion splitting device generates a random number Xi as a base parameter, wherein the first parameter KA=G^X