ATM cutting

ATM (automatic teller machine) is becoming more and more popular in Vietnam and almost every day readers will reflect on questions and problems related to this machine. How does ATM work and why does it crash? Let's dissect .

The "hard" and "soft" part

According to Mr. Do Duc Cuong - the "father" of ATMs, is currently the director of Dong A Bank computing - the principle of configuration of a 24-hour ATM operating in two parts: hardware and software.

Hardware includes specialized computers, cash register, cash register, diary printer, receipt printer, cryptographic key, card reader and iron cabinet. Hardware components must comply with very strict standards.

For example, the specific type of computer placed in an ATM is capable of identifying a system that is about to lose power. When preparing to lose power (the heat in the source is lowered), immediately (in half a second) the machine will record the situation in progress. When power is available, the machine will automatically start and rewrite the transaction.

Engineer Bui Phuong Nam, Dong A Bank, checked the diary before putting ATM into operation - (Photo: Thu Thao).

Money counting machine (spending money) mainly uses vacuum counting technique (pulling money up by force like a cupping) or friction technique. The cash register has the function of receiving cash directly sent by customers to the machine (currently only the East Asia Bank ATM has this function).

In addition, the cash receiver also accepts gift vouchers, bonds and converts into par value equivalent to cash.

In ATMs, a very important part is the diary printer. This printer will record all data related to the ATM: from the date the customer checks the card, the time of transaction, transfer, withdrawal .

This is also an important legal basis for resolving disputes. Once the diary printer does not work, the ATM will automatically stand.

The passcode key is also not the usual type of keyboard used to dial numbers. This keyboard is designed to be associated with security software. When you insert the card into the device and press the key, immediately the number is encrypted and erases all numbers that the user clicks on. No one can recognize the pin code number.

As for software, most ATMs must have an operating system (OS-operating system), device control software, self-recovery software (in case of a power failure), and a refund software (reversal) and security software.

For example, when a card user is withdrawing money, suddenly has a power outage, the user has not received the money while the account has been deducted.

Based on the recovery software and the refunded software, when the power is restored, the device will know the status before the power is turned off and automatically refund the amount not removed from the machine to the user's account. Security software will secure the information for the card and battery.

Why is ATM malfunctioning?

There are three things in the ATM system that are beyond the control of the governing body: data, electricity and weather. According to experts, these are the main causes of machine malfunction.

In addition, on holidays or on the end of the month, the number of cash withdrawals increased, ATMs were often overloaded and the phenomenon of 'fluttering' also occurred (at the time of withdrawing money, not withdrawing). .

Although by announcing the amount of money left on the system, the manager will know which ATMs are running out of money to plan to add money, but at peak times or there are cardholders who make the cash withdrawal. However, the bank staff could not put money into the machine, causing the machine to stop working.

The system also depends on the 'lightbulb' , for example, withdrawing money, if the ATM has a sudden power outage, the system often fails. During that waiting period, the system will keep the card until the power is restored.

One of the ATM incidents still occasionally encounters weather related issues.

One of the ATM incidents still occasionally encounters weather related weather, on days when the humidity in the air is high, moisture makes money easily stick together. When using the technique of withdrawing money by vacuum, there is still a phenomenon of withdrawing a sheet but sometimes going to . two sheets.

In addition, due to security factors, ATM is intentionally designed to be unable to distinguish the currency at face value, so if the employee misclasses the money in the box, the machine cannot identify itself ( In fact, there were cases where a bank's staff mistook the money with a par value of VND 100,000 into a tray of VND 50,000, so when paying the customer the amount received doubled the amount of money traded on the machine while the account was deducted correctly. transaction amount).

For the safety of the system, many banking experts affirmed: in Vietnam, the situation of criminals using fake cards to withdraw money has not been discovered.

Until this time, the loss of money on the account is still due to the cardholder not keeping the pin secret, giving the card to someone else to withdraw money or being stolen by a relative. However, according to Nguyen Trong Khang, director of MK Smart Card Joint Venture Company, magnetic cards currently in use are at a very high risk of counterfeiting.

If the crook captures the data on the track (the part containing the information) of the magnetic strip (card number, symbol code structure .) or information about the customer code, then making a fake card can still happen. .

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