Requirements document for anAutomated Teller Machinenetwork(ATM)
Product FunctionThe software should support a computerized banking network.Each bank provides its own computer to maintain its ownaccounts and process transactions against them. Automatic tellermachines communicate with the banks computers. An automaticteller machine accepts a cash card interacts with the usercommunicates with the bank computer to carry out thetransactiondispenses cash and prints receipts The system requiresappropriate record keeping and security provisions. The systemmust handle concurrent access to the same account correctly. Thebanks will provide their own software for their own computer.The cost of the shared system will be apportioned to the banksaccording to the number of customers with cash card.
AssumptionATMA station that allows customers to enter their owntransactions using cash cards as identification. TheATM interacts with the customer to gathertransaction information sends the transactioninformation to the central computer for validationand processing and dispenses cash to the customer.We assume that an ATM need not operateindependently of the network.
• If no cash card is in the ATM the system shoulddisplay initial display.• If the cash card is valid the ATM should readthe serial number and bank code.• If the ATM is running out of money no cardshould be accepted. An error message isdisplayed.• If the transaction is successful the money isdispensed.
Mathematical statementa) no cash card v ATM => system should displayinitial display.b) cash card is valid => ATM read the serialnumber.c) ATM is running out of money => no cardshould be accepted ∩ error messagedisplayed.d) transaction is successful => the money isdispensed.