Checking system for identity or credit card - uses comparison of number read from card with manually keyed personal code, effected through decoder as additional fraud precaution

摘要

A checking system is used for identity cards, credit cards, etc. with a card reader to read the number recorded on the card. There is provision for keying in a secret personal code by the person presenting the card, and there are systems to compare the number read from the card with that keyed in, with an additional decoder incorporated between the keyboard and the comparator. The effect is greatly to increase the difficulty of unauthorised use by a person who has obtained access to the decoding used to decode the card number by the equipment.