Bank teller machines rely on using information on the users

Bank teller machines rely on using information on the user’s card giving
the bank identifier, the account number and the user’s personal identifier. They
also derive account information from a central database and update that
database on completion of a transaction. Using your knowledge of ATM
operation, write Z schemas defining the state of the system, card validation
(where the user’s identifier is checked) and cash withdrawal.  

Solution

Solution:

A cash machine also known as an automated teller machine(ATM) .It is an electronic telecommunications device that enables the customers of a financial institution to perform financial transactions, particularly cash withdrawal, without the need for a human cashier, clerk or bank teller.

Most modern cash machines, the customer is identified by inserting a plastic ATM card with a magnetic stripe or a plastic smart card with a chip that contains a unique card number and some security information such as an expiration date or CVVC (CVV). Authentication is provided by the customer entering a personal identification number (PIN).

Using a cash machine, customers can access their bank deposit or credit accounts in order to make a variety of transactions such as cash withdrawals, check balances, or credit mobile phones. If the currency being withdrawn from the cash machine is different from that in which the bank account is denominated the money will be converted at an official exchange rate.

Most cash machines are connected to interbank networks, enabling people to withdraw and deposit money from machines not belonging to the bank where they have their accounts or in the countries where their accounts are held.

Security, as it relates to cash machines, has several dimensions. Cash machines also provide a practical demonstration of a number of security systems and concepts operating together and how various security concerns are

In some countries, multiple security cameras and security guards are a common feature.In the United States, The New York State Comptroller\'s Office has advised the New York State Department of Banking to have more thorough safety inspections of cash machines in high crime areas.

Consultants of cash machine operators assert that the issue of customer security should have more focus by the banking industry, it has been suggested that efforts are now more concentrated on the preventive measure of deterrent legislation than on the problem of ongoing forced withdrawals.