Bennet National Bank’s credit card department issues a special credit card that permits credit card holders to withdraw funds from the bank’s automated teller machines (ATMs) at any time of the day or night. These machines are actually smart terminals connected to the bank’s central computer. To use them, a bank customer inserts the magnetically encoded card in the automated teller’s slot and types in a unique password on the teller keyboard. If the password matches the authorized code, the customer goes on to indicate, for example, (1) whether a withdrawal from a savings account or a withdrawal from a checking account is desired and (2) the amount of the withdrawal (in multiples of $10). The teller terminal communicates this information to the bank’s central computer and then gives the customer the desired cash. In addition, the automated terminal prints out a hard copy of the transaction for the customer.
To guard against irregularities in the automated cash transaction described, the credit card department has imposed the following restrictions on the use of the credit cards whencustomers make cash withdrawals at ATMs.
1. The correct password must be keyed into the teller keyboard before the cash with drawal is processed.
2. The credit card must be one issued by Bennet National Bank. For this purpose, a special bank code has been encoded as part of the magnetic strip information.
3. The credit card must be current. If the expiration date on the card has already passed at the time the card is used, the card is rejected.
4. The credit card must not be a stolen one. The bank keeps a computerized list of these stolen cards and requires that this list be checked electronically before the withdrawal transaction can proceed.
5. For the purposes of making withdrawals, each credit card can only be used twice on any given day. This restriction is intended to hold no matter what branch bank(s) are visited by the customers.
6. The amount of the withdrawal must not exceed the customer’s account balance.
1. What information must be encoded on the magnetic card strip on each Bennet National Bank credit card to permit the computerized testing of thesepolicy restrictions?
2. What tests of these restrictions could be performed at the teller window by a smart terminal and what tests would have to be performed by the bank’s central processing unit and other equipment?