PURCHASE HISTORY PROVIDING METHOD, PURCHASE HISTORY PROVIDING SYSTEM, STORE SIDE INFORMATION PROCESSOR, PORTABLE DEVICE AND CUSTOMER SIDE INFORMATION PROCESSOR

摘要

PROBLEM TO BE SOLVED: To prevent purchase history of a purchaser from being read by a third person easily.;SOLUTION: A POS terminal 11 uses an encryption key 2 stored in an IC card 1 of a customer to encode the purchase history of the customer. Then, the POS terminal 11, via an IC card reader/writer 10, writes the purchase history in a purchase history record area 4 of the IC card of the customer. A customer side dedicated device 21, via an IC card reader/writer 20, reads out the purchase history encoded and written into the IC card 1. Then, the customer side dedicated device 21 uses a decryption key 24 held by the dedicated device 21 and decodes the purchase history.;COPYRIGHT: (C)2005,JPO&NCIPI