Shop apparatus, purchaser apparatus, purchaser identity proving apparatus, and purchaser identity verifying apparatus

A purchaser apparatus configured to communicate with both of a manager apparatus configured to pay for a purchaser's anonymous order by a group signature scheme having a tracing function, and a shop apparatus for accepting an anonymous order for a sales object by the group signature scheme, comprising:

• a storage device which is configured to store past “anonymous order information including an order ID, purchaser identity verifying information corresponding to the order ID and generated based on purchaser identity proving secret information, and a group signature” and “purchaser identity proving secret information”, in being correlated with each other, with respect to purchaser identity proving secret information which is itself unable to estimate from the manager apparatus and shop apparatus, and unable to estimate from the manger apparatus and shop apparatus even based on the purchaser identity verifying information generated based on the purchaser identity proving secret information;
• an anonymous order generating device which is configured to generate anonymous order information including an order ID, purchaser identity verifying information and a group signature, by the operation of a purchaser, when an order ID is received from the shop apparatus;
• an anonymous order sending device which sends obtained anonymous order information to the shop apparatus;
• a retrieving device which is configured to retrieve purchaser identity proving secret information concerning a past order ID from the storage device, by the operation of a purchaser;
• a zero knowledge proof generating device which is configured to generate zero knowledge proving information that a purchaser knows the purchaser identity proving secret information corresponding to the order ID;
• a request generating device which is configured to generate a request including the order ID and zero knowledge proving information, by the operation of a purchaser;
• and
• a request sending device which is configured to send an obtained request to the shop apparatus.

A purchaser identity proving unit to hold purchaser identity proving secret information written from a purchaser apparatus configured to communicate with both of a manager apparatus configured to pay for a purchaser's anonymous order by a group signature scheme having a tracing function, and a shop apparatus for receiving an anonymous order for a sales object by the group signature scheme, comprising:

• a secret information storing device which is configured to store purchaser identity proving secret information written from the purchaser apparatus upon initial setting;
• a zero knowledge proof generating device which is configure to be used independently of the purchaser apparatus, and to generate zero knowledge proving information that purchaser identity proving secret information concerning one or more pieces of past order ID is common and that a purchaser knows it, based on purchaser identity proving secret information in the secret information storing device, when the purchaser apparatus receives an order ID from the shop apparatus, after the purchaser apparatus generates anonymous order information including the order ID, purchaser identity verifying information corresponding to the order ID and generated based on purchaser identity proving secret information unable to estimate and a group signature, based on the “a secret calculation value that is calculated from the purchaser identity proving secret information upon initial setting and held”, and the purchaser apparatus sends the generated anonymous information to the shop apparatus, with respect to purchaser identity proving secret information which is itself unable to estimate from the manager apparatus and shop apparatus, and unable to estimate from the manger apparatus and shop apparatus even based on the purchaser identity verifying information generated based on the purchaser identity proving secret information;
• a request generating device which is configured to generate a request including the one or more pieces of order ID and zero knowledge proving information;
• and
• a request sending device which is configured to send an obtained request to “a purchaser identity verifying unit configured to obtain anonymous order information from the shop apparatus”.

A purchaser apparatus which is configured to communicate with both of a manager apparatus configured to pay for a purchaser's anonymous order by a group signature scheme having a tracing function, a shop apparatus for receiving an anonymous order for a sales object by the group signature scheme, and a purchaser identity proving unit for receiving the anonymously ordered sale object, and configured to write purchaser identity proving secret information into a purchaser identity proving unit upon initial setting, when the purchaser identity proving unit generates zero knowledge proving information that purchaser identity proving secret information concerning one or more pieces of past order ID is common and that a purchaser knows it, based on previously stored purchaser identity proving secret information, upon reception of the sales object, and sends a request including the one or more order ID and zero knowledge proving information to “a purchaser identity verifying unit configured to obtain anonymous order information from the shop apparatus”, comprising:

• a storage device which is configured to store past “anonymous order information including an order ID, purchaser identity verifying information, and a group signature” and “a secret calculation value calculated from purchaser identity proving secret information corresponding to an order ID and generated upon initial setting”, in being correlated with each other;
• a device which is configured to write the purchaser identity proving secret information into the purchaser identity proving unit, and to write the secret calculation value into the storage device, upon the initial setting;
• an anonymous order generating device which is configured to generate anonymous order information including an order ID, purchaser identity verifying information and a group signature, based on the secret calculation value, by the operation of a purchaser, upon reception of an order ID from the shop apparatus;
• and
• an anonymous order sending device which is configured to send obtained anonymous order information to the shop apparatus.

A purchaser identity verifying unit configured to obtain anonymous order information from a shop apparatus configured to communicate with both of a manager apparatus configured to pay for a purchaser's anonymous order by a group signature scheme having a tracing function, and a purchaser apparatus for making an anonymous order for a sales object by the group signature scheme, when “anonymous order information including an order ID, purchaser identity verifying information and a group signature” is received from the purchaser apparatus, after purchaser identity proving secret information corresponding to the order ID, purchaser identity verifying information generated based on the purchaser identity proving secret information corresponding to the order ID and unable to estimate, and a group signature based on the order ID and purchaser identity verifying information are generated by a purchaser apparatus in the past, with respect to purchaser identity proving secret information which is itself unable to estimate from the manager apparatus and shop apparatus, and unable to estimate from the manger apparatus and shop apparatus even based on purchaser identity verifying information generated based on the purchaser identity proving secret information, the shop apparatus stores the anonymous order information, issues an order ID based on sales object identifying information received from a purchaser apparatus of a purchaser, and sends the order ID to the purchaser apparatus, and when anonymous order information including the order ID, purchaser identity verifying information and a group signature is received, the shop apparatus verifies the group signature, and when the result of verification is valid, stores anonymous order recent information, and sends anonymous order information to the manager apparatus, comprising:

• a device which is configured to read one or more pieces of anonymous order information corresponding to “one or more past order ID” input after the anonymous order, from the shop apparatus, with respect to a purchaser identity proving unit, into which purchaser proving secret information is written from the purchaser apparatus upon initial setting;
• a storing device which is configured to store one or more pieces of anonymous order information read from the shop apparatus;
• a device which is configured to accept a request including “one or more past order ID” and “zero knowledge proving information that purchaser identity proving secret information corresponding to the one or more order ID is common and that a purchaser knows it”, from the purchaser identity proving unit;
• a zero knowledge verifying device which is configured to verify the zero knowledge proving information, based on one or more pieces of purchaser identity verifying information included in one or more pieces of anonymous order information in the storing device, upon acceptance of the request;
• and
• a request accepting device which is configured to accept the request, when the result of verifying the zero knowledge proving information is valid.