Terminal troubleshooting of flash cards

Reprinted please indicate the source

Author: Pony

Imagine a situation where the qpboc card is consumed, in the Data Reading and application phase, the terminal sends a read record command, and the card returns one record. When the card returns the last record, the card is instantly away from the terminal. terminal "failed to read the last record ". in this case, the card thinks that the interaction is over and successful, and it will deduct the money, but the hacker will report an error. This purchase fails for the terminal, of course, the merchant will not give the goods to the cardholder, And the Cardholder will suffer.

There is no such excuse as "this rarely happens." It is certainly possible to happen. Here we will discuss how to deal with this situation?

Let's talk about a method that UnionPay has adopted very early. when the terminal determines that it failed to read the last record, it will save the transaction and send the transaction to the background System in the batch settlement phase, in this way, the background system is like knowing "this". If the cardholder complains, the money can be returned to the cardholder. in fact, the terminal only implements "record-Send", and the specific processing is completed by the background system. what should I do if I require the terminal to "solve it by myself?

 

In general, the terminal saves the data with a flash card and processes the same card again. However, it only executes the application selection and read application data without issuing the GPO command, in this way, the fee will not be deducted repeatedly.

 

The detailed process is as follows:

Under normal circumstances, each transaction is completed by the terminal. Before the next transaction starts, the terminal also stores the previous data, such as AFL, ATC, primary account, and balance, when the terminal detects a flash card, the terminal prompts that the transaction failed, and then asks for another card. After the card is detected again, the terminal can pass a series of conditional judgments, whether the card has just appeared as the flash card. If yes, the terminal only sends the application selection and then reads the application data according to the AFL of the previous one, the subsequent procedures are the same as normal transactions.

The conditions for judging the same card mentioned above generally need the following:

 

Whether the 1-card serial number is the same, which can be obtained when the card is not connected.

2. Whether the ATC is the same. After selecting an application, you can use get data to retrieve it.

3. Balance: The obtained current balance. The balance saved in the previous transaction is equal to the transaction amount in the previous transaction.

If it is determined that the replay is not the same card, the processing will be more flexible, and different application scenarios can be handled differently, in addition, the processing method depends on the number of "flash cards" records that can be stored by the terminal.

Please shoot bricks.