Device for sharing anonymized information, and method for sharing anonymized information

An anonymized information sharing apparatus that shares anonymized information with another apparatus, a sender of the anonymized information being anonymous, the apparatus comprising:

• an authentication ID generating section comprising a processor that generates, for each piece of information to be shared, a process password by applying a first one-way function to a combination of an individual password and a data ID and an authentication ID by applying a second one-way function to a combination of part or all of the information to be shared and a process password;
• an anonymizing section that generates the anonymized information by adding the authentication ID to the information to be shared;
• an information sharing section that sends the generated anonymized information to the other apparatus and causes the other apparatus to hold the generated anonymized information and holds the anonymized information sent to the other apparatus and anonymized information sent from the other apparatus;
• an individual identification risk monitoring section that monitors a risk of the sender of the anonymized information sent to the other apparatus being identified, based on the anonymized information held in the information sharing section;
• and
• an anonymized information processing requesting section that, if the risk is high, generates and transmits a process request containing the process password to the other apparatus and requests the other apparatus to perform a process of lowering the risk for the anonymized information held in the other apparatus on the basis of a match between the authentication ID of the anonymized information held in the other apparatus and a result obtained by applying the second one-way function to the combination of part or all of the anonymized information held in the other apparatus and the process password.

A method of sharing anonymized information with another apparatus, a sender of the anonymized information being anonymous, the method comprising:

• generating a process password by applying a first one-way function to a combination of an individual password and a data ID and generating, for each piece of information to be shared, an authentication ID by applying a second one-way function to a combination of part or all of the information to be shared, the process password, and the data ID;
• generating the anonymized information by adding the generated authentication ID to the information to be shared;
• sending the generated anonymized information to the other apparatus and causing the other apparatus to hold the generated anonymized information;
• and
• generating and transmitting a process request containing the process password to the other apparatus and requesting the other apparatus to perform a predetermined process on the basis of a match between the authentication ID of the anonymized information held in the other apparatus and a result obtained by applying the second one-way function to the combination of part or all of the anonymized information held in the other apparatus, the process password, and the data ID, the predetermined process being permitted only by the sender.