JPH0347546B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention is used as an identification means in an automatic transaction device of a financial institution, etc., to check the correspondence between magnetic card data and manually input data by a transactor, and to take appropriate action. This invention relates to a method for preventing fraudulent transactions in automatic transaction devices that validates transactions only when there is a relationship.

[Background of the invention]

Conventionally, methods for preventing fraud in automatic transaction devices of this type include eliminating the PIN number from the magnetic card;
Instead, the true PIN is calculated using a formula from confidential information, auxiliary information, etc., and compared with the customer input code to prevent unauthorized users from reading the PIN from the magnetic card. etc. have been proposed, but the judgment is made only by either the automatic transaction device side (offline method) or the center side (online method), which lacks confidentiality and is especially true in the online method. had a drawback in terms of line confidentiality.

(Patent Application Publication No. 54-23787) [Object of the Invention] The object of the present invention is to provide a method for authenticating a transaction person in which the PIN number is not stored or transferred in its original form in cards and automated transaction devices; The purpose is to improve the confidentiality of numbers.

[Summary of the invention]

The present invention stores a first cryptographic key and a surface password encrypted with the first cryptographic key on the card, and stores a second cryptographic key and a pseudo password encrypted with the second cryptographic key in a storage area for each user in the central system. Remember your PIN number. Then, the terminal device compares the PIN entered by the user with the cipher number restored from the front PIN using the first encryption key, and when these satisfy a specific relationship, transfers the front PIN to the central system; The central system determines whether the surface PIN and the pseudo PIN have a specific relationship using the first and second cryptographic keys, and allows the transaction if they have a specific relationship.

The PIN number is not stored on the card or in the central system, and is not transferred between the terminal and the central system. In addition, the password check is performed both at the terminal device and at the central system.
Therefore, it is difficult to read the password or forge the card.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention intended for an automatic teller machine will be described below with reference to the drawings.

FIG. 1 shows a block diagram related to the present invention, in which 1 is a card reader/recorder that reads information from a card and writes new information after a transaction, 2 is a cash dispensing unit including a cash counting unit, and 3 1 is an operating unit including a keyboard, 4 is a display unit, 5 is a control unit, 6 is a transmitting/receiving unit, 7 and 8 are modems, 9 is a line, 10 is a transmitting/receiving unit on the center side, 11 is a central processing unit, and 12 is a main unit. A storage device 13 is an external storage device that stores customer master files and the like.

To explain this operation, data such as the bank number, branch number, account number, and PIN number recorded on the magnetic card is read by the card reader recorder 1, and if the data such as the bank number is valid, the customer A guide is displayed on the display section 4 to input the password from the operation section 3. When the personal identification number is thus properly input, a guide is displayed on the display section 4 to similarly input the payment amount from the operation section 3. When these predetermined procedures are completed, the control device 5, the transmitting/receiving device 6,
It is sent to the central processing unit 11 via the modem 7, line 9, modem 8, and center-side transmitting/receiving device 10.
The central processing unit 11 rechecks the bank number, account number, PIN number, etc. that are part of the data based on the data recorded in the corresponding account number storage area of the customer master file 13, and if it is correct, The user is instructed to pay cash from the cash payment section 2.

At this time, even if the center checks the PIN number again to prevent tampering of the PIN number on the magnetic card, the method of recording the PIN number itself on the magnetic card makes it impossible to decipher it. It is also possible to fraudulently withdraw cash by forging another card. Also, even if you eliminate the PIN number from the magnetic card and use a method that calculates the true PIN number from completely different confidential information using a predetermined formula,
In the conventional method of checking only on the center side, there is a high risk that the data on the line will be decoded or that it will be decoded by someone inside the center, and it is possible to forge a card using only the data in the customer master file at the center. This can be said to be even more dangerous in systems.

Therefore, in the present invention, the true PIN number is not recorded directly on the card, but a surface that is obtained by mathematically processing a plurality of customer transaction information that changes each time a customer makes a transaction, and the plurality of customer transaction information and the true PIN number. In addition to recording the PIN, the center customer master file also contains a random number corresponding to the account number, a pseudo PIN obtained by mathematically processing the random number and the true PIN, and multiple customer transaction information similar to that on the card. By recording the data, both the automated teller machine and the center can independently check the validity of the data, and it also makes it possible to eliminate PIN numbers from the line, which solves the problems of the past. This is an attempt to resolve the issue.

This will be explained below with reference to the drawings.

FIG. 2 shows an example of the format of a magnetic card used in the present invention.

In the figure, numeral 21 is a password field, which is always set to "0" here. 22 is the bank number column, 23 is the branch number column, 24 is the account number column, 2
Reference numerals 5 and 26 are customer transaction information columns that change for each transaction, where 25 is the card balance and 26 is the card processing serial number. This card balance is the balance at the time the customer makes a card transaction, and may not always match the normal balance. Further, the card processing serial number is a serial serial number for each automated teller machine that processes the card at the center. Also, 27 is the front password field, and the above 25, 2
This is calculated from the secret information calculated from the customer transaction information in step 6 and the true PIN number.

In addition, the customer transaction information fields 25 and 26 and the front PIN field 27 are set to "0" when the card is issued.
Each value is set by the customer's own password registration procedure.

FIG. 3 shows an example of the customer master file format of the center according to the present invention.

In the figure, 31 is an account number field assigned to each customer, 32 is a PIN registration mark field, and 33 is a pseudo-PIN field, which is calculated from a random number and a true PIN number. Numeral 34 is a random number column, and 35 and 36 are customer transaction information columns in which data similar to that of the magnetic card is recorded.

Furthermore, from the PIN registration mark field 32 to the customer transaction information fields 35 and 36, "0" is set when the card is issued, and each value is set by the customer's own PIN registration procedure. be.

FIG. 4 shows the process of registering a password. Registration of the PIN number is performed based on the customer's own operations.

A customer inserts a card issued by a bank into a card reader 1. Under the control of the control device 5, the card reader 1 reads the bank number, branch number, and account number. The card balance, card processing serial number, and front PIN fields are all 0. Next, when the customer enters a personal identification number (true personal identification number) A, it is read and the information thus read is transferred to the central processing unit 11. The central processing unit 11 receives this information and generates a random number R;
After reading the balance Z and processing serial number T of the account number, the following equation is calculated. The formula below is just a simple example,
A different arithmetic expression may be used.

Formula 1 Secret information (S) = (Z) + (T) Formula 2 Front password (H) = (A) + (S) Formula 3 Pseudo password (G) = (A) + (R) After this calculation, Write the pseudo PIN G and random number R card balance Z in the area corresponding to the account number in the customer master file. Also, the card processing serial number is updated from 0 to 1 and written. The password registration mark is now written into the customer master file.

Although the explanation is confusing, the PIN registration mark is read before the above calculation, and if this mark is not recorded, the above process is performed, and if this mark is recorded, for example, an unauthorized card user can This is used to stop future transactions, assuming that the PIN is being re-registered using a fraudulently created card, or that the PIN is being re-registered using an fraudulently created card.

Information including the front PIN, updated card balance, and card processing serial number is transferred to the transaction terminal. Here, these are written to the card under the control of the control device 5.

Next, an explanation will be given with reference to FIG. 5, which schematically shows the operation at the time of automatic cash payment from the automatic teller machine using a card registered with a password.

When the customer inserts the card, the account number, balance, processing serial number, and front PIN are read from the card.
The true PIN number (customer registration PIN number) is calculated using the above formula. Next, the input PIN entered by the customer is compared with the calculated true PIN, and if the result is correct, the transaction information (deposit, etc.) is sent to the central system.
payment type, amount, etc.) card information (account number,
(front PIN, etc.).

Based on the account number on the card, the central system uses a pseudo PIN, random number,
The balance and processing serial number are read, the front PIN is calculated using the above formula, and the front PIN is compared with the sent front PIN data. If the results are not equal, the transaction is stopped as an error; if the results are equal, the transaction is deemed to be valid.Based on the new customer transaction information (balance, processing serial number) after the transaction and the newly calculated surface PIN,
Respectively customer master file or update magnetic card and pay cash.

At this time, derive the true PIN from the surface PIN,
A pseudo password may be obtained by performing calculations using random numbers, and this may be compared with a pseudo password stored in the customer master file to detect whether or not they match.

As described above, according to this embodiment, the customer's own password registration procedure can prevent the password from being leaked to others. In addition, the customer himself/herself may not be aware of it and
By recording information on the card that changes depending on each transaction (processing serial number, etc.), it is impossible to forge the card even if the customer is tricked into obtaining the PIN number. Furthermore, there is no surface PIN on the customer master file of the central system;
Also, since the true PIN number is not sent over the line,
Even if an attempt is made to decipher the information, it will be impossible to forge or use the card fraudulently.

Further, in this embodiment, the balance is used in the calculation formula for the password check, and it is clear that this has the effect of preventing cash accidents due to unauthorized tampering of the balance.

Although the above embodiments are directed to automated teller machines, the present invention is not limited thereto. In other words, it can be applied to various types of personal authentication such as money transfers, check issuance, and securities transactions. Furthermore, in this application, the term "card" refers not only to a magnetic card, but also to a card with an information recording medium, such as a card with an IC chip attached.

〔Effect of the invention〕

According to the present invention, the customer's PIN number is stored on the card.
It can be removed from the center customer master file and even from the line, ensuring a high level of confidentiality. Furthermore, card counterfeiting can be eliminated by recording information on the card that cannot be recognized by the customer and that changes depending on each transaction.

Based on the above, there have been concerns about card forgery and card fraud by card registrars or center operators.Card fraud by those who obtained the card illegally.Card forgery by people who illegally copied the card.Card forgery by data decipherers on the line. It is possible to eliminate all fraudulent card usage and provide safe automated transactions.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of an automated teller machine, FIG. 2 is a diagram showing an example of the format of a magnetic card used in the present invention, and FIG. 3 is a diagram showing an example of the format of a center customer master file.
FIG. 4 is a flowchart showing the operation at the time of registering the customer's personal identification number, and FIG. 5 is a block diagram showing the operation at the time of cash payment according to the present invention. DESCRIPTION OF SYMBOLS 1...Card reader recorder, 2...Cash payment section, 3...Operation section, 4...Display section, 5...Control device, 11...Central processing unit.

Claims (1)

[Claims] 1. A central system equipped with a storage device having a storage area for each transaction person, and a transaction terminal device equipped with a means for reading the card of the transaction person and an information input means into which PIN information is input by operation of the transaction person. A method for authenticating a transaction person in a transaction device having a card, which stores a first encryption key and first information in which the personal identification information is encrypted using the first encryption key, and stores a second information in the storage area of a central system. storing a cryptographic key and second information by which the password information is encrypted, and restoring using the first cryptographic key from the password information and first information input from the input means in the transaction terminal device; Compare the password information and
When they have a specific relationship, the first information is transferred to the central system, and the central system uses the first and second encryption keys to identify the first information and the second information.
A transaction authentication method that determines whether or not the information of the transaction is in a specific relationship, and authenticates that the transaction is valid when the transaction is in a specific relationship.