JPS5932059A - Illegality preventing system - Google Patents

Abstract

PURPOSE:To prevent forgery of a card due to tapping of a secret number, by qualifying the secret number with a specific code to transmit it to a central processor from a terminal, and restoring and collating the qualified secret number at the central processor. CONSTITUTION:A message sent from a central processor 200 is decoded 28, and a specific code is extracted and stored in a specific code register 29 provided at a message control circuit 24 of an automatic cash transaction device. The processor 200 sets and changes the specific code unperiodically at each terminal, then registers it to a specific code table. A secret number is extracted from a message supplied from the cash transaction device and then registered 30. Then the secret number is added 31 at the register 29, and a message is composed 27 and transmitted via a secret number register 32. The processor 200 restores a qualified secret number and discriminates the genuineness of the number. As a result, a card forged by tapping is unusable to prevent a false use of the card.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for preventing fraud, and in particular, in an automatic cash transaction system, it is possible to use a cash transaction medium such as a magnetic card or a magnetic passbook on which personal identification information such as a PIN number is recorded with an original image. Relates to a fraud prevention method that prevents use by anyone other than the owner.

Recently, in the banking industry, automated cash withdrawal machines (CDs)
, automatic teller machine (AD) l automatic teller machine (ATM)
), etc., are connected online to a central processing unit via a communication line. A so-called automatic cash transaction system has been put into practical use. In this system, when a user makes a cash transaction such as deposit, savings, transfer, etc., a cash transaction medium such as a magnetic card or magnetic passbook given to the user is used, and the user makes a cash transaction. The rightful owner of the medium is confirmed.

In order to prevent such unauthorized use of magnetic cards, for example, various techniques have been proposed in the past.

- To give an example, this is the technique described in Japanese Patent Publication No. 45-2157, Japanese Patent Publication No. 49-29083, 1% Publication No. 50-24576, etc. According to these techniques, a situation where a third party other than the user fraudulently uses the user's magnetic card to conduct a cash transaction is prevented.

On the other hand, by intercepting and eavesdropping on the communication line connecting the central processing unit and the automated teller machine, a third party can learn the contents of messages on the communication line, including the contents of the magnetic card.
Extremely malicious situations have actually occurred in which people forge magnetic cards and then use these magnetic cards to conduct automated cash transactions as described above. However, in such a situation, the magnetic card is made much better than the real thing, and the user also deciphers the PIN number recorded on the magnetic card from the above message, so the above-mentioned error occurs. The techniques described in the known examples cannot prevent such fraud.

Furthermore, a technique is also known in which an automated teller machine scrambles and encrypts a password recorded on a magnetic card or magnetic passbook according to preset rules. However, according to this type of technology, it is possible to see through the rules of scrambling by comparing the data on the communication line with known data, so it is not a perfect means to prevent fraud. I don't have an older brother.

An object of the present invention is to make it impossible for a third party to decipher personal identification information in an automated cash transaction system, even if messages on a communication line connecting an automated teller machine and a central processing unit are intercepted or wiretapped. Furthermore, it is an object of the present invention to provide a fraud prevention method that prevents counterfeiting of cash transaction media.

Accordingly, the present invention provides an automatic cash transaction in which an automatic cash transaction is performed using a central processing unit and a cash transaction medium connected to the central processing unit via a communication line and recorded with personal identification information. This is realized in a system comprising a device. That is, the specific food is sent from the central processing unit to the automatic teller machine.

The automatic teller machine includes a storage means for storing this specific code, and a storage means for storing the specific code, and a method for transmitting transaction information from the automated teller machine to the central processing unit via a communication line based on the specific code. Modification means are provided for modification. On the other hand, the central processing unit is provided with means for restoring the transaction message modified by the specific code to the original transaction information. As a result, messages sent over a communication line are modified with a specific code, so even if the line message is intercepted or tapped, it will be extremely difficult to decipher the personal identification information.

Furthermore, if the specific code is changed and modified as appropriate, it becomes impossible not only to decipher this type of code but also to forge cash transaction media.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is a diagram showing the configuration of an automated cash transaction system to which an embodiment of the present invention can be applied. In this diagram, an automated teller machine (hereinafter simply referred to as a "transaction machine") 1
00 is a device having, for example, a cash payment function and a balance inquiry function. This transaction device 100 has a communication line 300
It is connected to the central processing unit 200 via. In this embodiment, a publicly known magnetic card is used for cash transactions, and for example, this card has a format defined by the bank uniform specifications, and includes a bank number, branch number, and user identification i'r.
Account numbers, passwords, etc. that serve as f-reports are magnetically recorded.

Now, in the transaction device 100, the receiving port 11 is an opening through which the transaction result slip and cash are sent out. When these sending operations are performed, a shutter (not shown) opens and the user receives the transaction result slip and cash. Vote and cash can be accepted. Card port 12 is an entrance into which the magnetic card is inserted. The inserted magnetic card is conveyed to the magnetic card reading section 13, where the recorded information is read. The read information is sent to control unit B. Numerical keys 15 are tQ#, t
It consists of digits 9r and is used to select the transaction item, enter the PIN number, and the transaction amount. That is, when there are multiple types of transaction items, such as payment items and balance inquiry items, the numeric keys 15 are used because the transaction items are guided in correspondence with the numeric keys. Note that an amount key 18 is provided to distinguish whether the input numerical value is a password or an amount of money, and if the inputted numerical value is an amount of money, this is then pressed. The input numbers from the numeric key 15 are read by the reading section 1.
4 and sent to the control unit.

The amount information entered by the numeric keys 15 is sent to the character display 16 by the control unit and displayed.

This is to make the user confirm the input amount. In this confirmation operation, when the user approves the content displayed on the character display 16, the magazine key 19 is pressed. The control unit receives this pressing signal of the confirmation key 19 and starts various calculation processes. On the other hand, in this confirmation operation, if the user does not approve of the displayed content, the user presses the cancel key. When the control unit n receives the press signal indicating that the cancel key has been pressed, it drives a guidance text display 17, which will be described later, in order to allow the user to correct the input operation.

The guidance wording display 17 is for displaying matters to be operated by the mother-in-law as guidance. Applicable literary words are selected and displayed at appropriate times under the control of the control unit.

The banknote payment mechanism 21 takes out the number of banknotes specified by the control unit from a cassette (not shown) and conveys them to the receiving slot 11. The slip issuing mechanism n is a central processing unit 200 which will be described later.
The slip print data in the response message sent from the controller is printed on the statement slip under the control of the control unit. This statement slip is conveyed to the receiving slot 11 and discharged.

The control section n controls each of the above-mentioned mechanical sections in order to cause them to perform predetermined operations, and also processes information input and output from each mechanical section. Further, a message control circuit U in this control unit n handles transaction messages sent to the central processing unit R200 and response messages sent from the central processing unit 200.

Manage the decoding, editing, etc. of start messages, etc.

The format of these messages and the control circuit will be detailed later.

The central processing unit 200 has a large-capacity storage device, and stores deposit balances of users in correspondence with account numbers. Then, upon receiving a transaction message from the transaction device 100,
It decodes this, calculates and updates the deposit balance corresponding to a certain user's account number according to the transaction item, edits a reply message, and sends it to the transaction device 100.

FIG. 2 shows messages sent between central processing unit 200 and transaction device 100. These messages are edited, decoded, etc. by the message control circuit and central processing unit 200 of the transaction device 100.

Now, as mentioned above, the transaction message shown in (&) is sent to the transaction device 1 by the user pressing the confirmation key 19.
00 to the central processing unit 200. Here, the terminal status information includes information necessary for the central processing unit 200 to process the transaction, such as the type of transaction device, identification number, or type of transaction. The transaction amount is the withdrawal amount in the case of a payment transaction.

The magnetic card data includes the recorded contents of the magnetic card defined by the bank uniform specifications, ie, the bank number, branch number 2, account number which is personal identification information, and personal identification number.

The response message shown in (b) transmits information resulting from processing by the central processing unit 200 to the transaction device 100 in order to complete one transaction process. This includes terminal control information, date information, account number, transaction amount, slip print data, and specific code. As will be described later, the specific code is valid in this embodiment.

The start message shown in (C) is used as a start signal at a certain time every morning when starting the operation of the transaction device 100, for example.
Alternatively, after a failure occurs and the operation of transaction processing is temporarily interrupted, the signal is sent from the central processing unit R200 to the transaction device [100] as a startup signal for starting up the transaction device 100. Here, a specific code is included in the start message, the significance of which will be described later.

Figure 3 shows the message control circuit 2 in the control section of the transaction device.
4 is shown.

Recorded contents of the magnetic card inserted into the card number 12 and read by the magnetic card reading section 13, and transaction items inputted from the numerical keys 15 and coded by the reading section]4,
Information such as the personal identification number and transaction amount is input to the message assembly circuit n as an input signal.

As mentioned above, the message assembly circuit 27 is shown in FIG.
Assemble the transaction message shown in and send it to the sending buffer 5 to V.
It is sent to the communication line 300. The response message and initiation message transmitted from the central processing unit 200 are received via the reception buffer 26 and are decoded by the message decoding circuit. The specific code in the message is
It is stored in the message decoding circuit and the specific code register 4. The contents of the corregister 29 are the central processing unit! 2
It is held from 00 until a new specific code is received.

The message assembling circuit n sets the PIN number in the input signal in the first PIN register I when assembling a transaction message from the input signal. The addition circuit 31 inputs the contents of the specific code register 4 and the first password register (9).
Add the contents of. The result is set in the second PIN register 32.0 The message assembly circuit 27 inputs the PIN number to be included in the magnetic card data in the transaction message into the PIN code in the input signal when the transaction message decoding circuit is used. Not from the number, but from the second PIN register 32
Create from the contents of. Therefore, the PIN included in the transaction message is not the PIN entered by the user using the numerical keys 15, but is a value modified by a specific code sent from the central processing unit 200, for example, in the start message. Become.

Here, the function and handling of the specific code, which is characteristic of this embodiment, will be explained in more detail.

This birch given code is generated in the central processing unit 200, included in the start message and a part of the response message, and sent to the transaction device 100 from the central processing unit ft200. This specific code is not fixed; for example, the transaction device at the destination may have a code that differs depending on the time of day, and the central processing unit 200 manages the correspondence between the transaction device that sent the message and its specific code. It has a table.

When a transaction message is received from a certain transaction device 100, the central processing unit 200 decodes the transaction message and performs cash transaction processing. At this time, the transaction device that should perform the transaction process is recognized from the terminal status information in the transaction message, and the table is searched to extract the specific code sent to the transaction device. Furthermore, this specific code is subtracted from the modified password included in the magnetic card data in the transaction message, and the password is returned to the password before being modified or changed by the message assembly circuit n.

The value of this PIN is the original PIN that the user registered when opening an account at the bank, and the central processing unit 200
compares the PIN number registered at the time of account opening with the PIN number restored to its original form.

This allows a check to be made as to whether or not the user is the legitimate holder of the magnetic card. That is, if there is a match as a result of the verification, the account number of the user is accessed and a transaction process, for example, a deposit balance update process is performed. On the other hand, if they do not match, the transaction process will not be performed and a response message to that effect will be sent to the transaction device.

Now, suppose that a third party other than the original user intercepts and eavesdrops on the transaction message through the communication line 300, and forges a magnetic card based on the magnetic card data therein. However, the PIN number in the above magnetic card data has been modified, and this third party cannot know the original PIN number (the PIN registered when opening the account), so this type of forgery is not possible. The transaction device cannot be operated using a magnetic card. Furthermore, even if the specific codes in the response message and the start message were known, and even if the algorithm for modifying the PIN number as described above was known, the transaction device or time when a counterfeit magnetic card is used later would be Since it is almost impossible for the
The central processing unit detects discrepancies in the PIN numbers, thereby preventing unauthorized use of the magnetic card. Although various methods can be considered for generating the specific code, for example, the total number of transactions of all transaction devices connected to the central processing unit 200 may be accumulated and the last four digits may be used. Such values are random values from the perspective of a specific trading device,
Moreover, it changes over time and can be easily generated.

In this way, according to this embodiment, even if a third party intercepts and eavesdrops on messages on the communication line 300 that connects the transaction device lOO and the central processing unit R200, there is no regularity in the data in the messages. It is possible to prevent unauthorized use such as forging the magnetic card of an authorized user and withdrawing money from that user's account.

Although one embodiment of the present invention has been described above, it can be implemented with various other modifications. For example, in the above embodiment, an example was explained in which the PIN number in the message is modified, but not only the PIN number but also the account number may be modified.Also, the entire message may be modified. . Further, in the above embodiment, the central processing unit generates the specific code itself, but the transaction device 100 may modify the message using a predetermined modification method according to the number of turns of the specific code. .

Furthermore, the above embodiments can be applied not only to magnetic cards but also to cash transaction media such as magnetic passbooks.

As explained above, according to the present invention, even if a third party intercepts or eavesdrops on the messages on the communication line connecting the automated teller machine and the central processing unit, the identity of the holder of the cash transaction medium can be identified. The information is not known to a second party, therefore, the cash transaction medium is forged based on the wiretapping, and unauthorized automatic cash transactions using this medium are prevented.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an automated cash transaction system to which an embodiment of the present invention is applied; FIG. 2 is a diagram showing the format of a message sent between a transaction device and a central processing unit; and FIG. FIG. 2 is a block diagram showing the M configuration of the message control circuit shown in FIG. 1. 100... Automatic cash transaction device, 200... Central processing unit, 300... Communication line, 24... Message control circuit. Agent Patent attorney Tadashi Akimoto Figure 1 Figure 2 (a) Transaction mechanism (b) Transaction mechanism 11. sage′

Claims (1)

[Scope of Claims] 1. A terminal device on which a certain type of transaction is conducted using a transaction medium in which personal identification information is recorded, and a terminal device connected to the terminal device via a communication line and connected to the terminal device through the communication line. In a system equipped with a processing device that performs some kind of transaction processing based on messages sent from a terminal device and returns processing results to a terminal device, the terminal device stores a specific code sent from the processing device. and a modifying means for modifying at least personal identification information of a message transmitted from the terminal device to the processing device with the specific code, and the processing device also includes information modified by the specific code. % to have the means to restore
A fraud prevention method based on the characteristics. 2. The fraud prevention method according to claim 1, wherein the terminal device is an automatic teller machine, and the transaction medium is a magnetic card on which at least a personal identification number as personal identification information is recorded. . 3. The processing device generates a variable specific code, and
3. The fraud prevention system according to claim 2, further comprising means for managing a relationship between the automatic teller machine that transmitted the specific code and the specific code.