JPS62296269A - Ic card system - Google Patents

Abstract

PURPOSE:To prevent illegal transactions due to continuous use through off-line by making the number of times of continuous use through off-line range within the number of required times uncertain. CONSTITUTION:If the frequency of continuous use through off-line is <=4 times, unconditionally transactions are established. If the frequency exceeds four, a random number generator 68 generates random numbers, and transactions through off-line are allowed with some possibility according to the value of the random numbers. The frequency of continuous use through off-line is not set to a definit number, but falls into a range of five - 18. Thus, if an IC card is illegally used through the continuous use of off-line, it fails because the frequency cannot be specified. Illegal transactions through off-line can be prevented, and safety in terms of off-line can be improved.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Technical Field of the Invention] This invention provides an IC for preventing offline fraudulent transactions.
Regarding the card system.

[Prior art and its problems] In recent years, it has become known as the cashless era, and by using cards issued by credit card companies, it has become possible to purchase products without handling cash.

Conventionally, cards used include plastic cards, embossed cards, and magnetic striped cards, but these cards are easy to forge due to their structure, so unauthorized use has become a problem.

Therefore, in order to solve this problem, we have developed an information card that incorporates an IC circuit that stores the PIN number etc. inside the card so that the PIN number cannot be easily read from the outside.
An IC card has been considered, and an IC card system that combines such an IC card and a terminal has been developed.

By the way, in such an IC card system, in addition to using the IC card online through a terminal connected to a computer at a bank, etc., there is also the possibility of using the IC card alone through a terminal installed at a store. , so-called offline use is possible. However, especially offline, data management is distributed to each terminal, making it easy for various card crimes to occur.

Therefore, in conventional IC card systems, in order to prevent offline card crimes, for example,
Countermeasures are being considered, such as determining the transaction amount per transaction. However, even with this method, in the conventional IC card system, the limit amount is managed for each terminal, so just by changing the store you shop, you can make a transaction regardless of the limit amount, making it difficult to commit crimes. If used for this purpose, the amount of damage could be enormous.

On the other hand, in order to prevent such inconveniences, a device in which the number of consecutive offline uses is set to a constant value has been considered. However, in this case, once the number of consecutive offline uses is known, there is a possibility that fraud can be safely committed within this range, and the security of offline use is significantly deteriorated.

[Purpose of the Invention] This invention was made in view of the above circumstances, and it is possible to prevent unauthorized offline use by making the number of consecutive offline uses indefinite within a predetermined range, thereby improving safety. The purpose of this invention is to provide an IC card system.

[Summary of the Invention: The IC card system according to the present invention has an IC card and a terminal to which the card is installed, and if the IC card is used offline for a preset number of times or more, Transactions are now disabled.

[Embodiments of the invention] An embodiment of the present invention will be described below with reference to the drawings.

First, Figure 1 shows the terminal 1 where the IC card 5 is installed.
This figure shows the circuit configuration of . In the figure, 11 is a system bus, and this system bus 11 includes a sound controller 12, a working RAM 13, a system program ROM 14, a terminal attribute ROM 15, an initial parameter RAM 16, a main controller 17,
Display drive controller 18, key controller 19
, reader/writer controller 20, comparator 21, rR8
An encryption unit 22 that performs encryption based on the AJ algorithm, an output buffer 24 via an output controller 23, and an input controller 26 via an input buffer 25.
are connected respectively.

A speaker 27 is connected to the sound controller 12 and outputs an alarm sound as necessary.

The working RAM 13 stores rPANJ, rcHNJ, rEPDJ sent from the IC card 5 side in the memory area.
, etc. are stored, as well as various processing data within the terminal 1.

The system program ROM 14 contains EN for matching with the IC card 5 along with each scale system program.
Equipped with Q code etc.

The terminal attribute ROM 15 stores terminal codes TC (for example, manufacturing code, issue code, store code, etc.) depending on the purpose of the terminal.

Initial parameter RAM 16 stores answer-to-reset data from IC card 5 all at once. This initial parameter RAM M16 includes transmission line 1.
The output controller 23, the input controller 26, the vpp level latch section 28, the Vpp timer latch section 29, and the Ipp level latch section 30 are connected through the latches 2'8, 29, and 30. 32, Ipp limiter 33 is connected.

Here, the pp power supply 31 is for securing the voltage Vpp used for writing data into the data memory of the IC card 5. In addition, the Vpp timer 32 is
This is to ensure the maximum unit processing time specified by. Roughly speaking, the pp limiter 33 determines the permissible value of the data write current.

In this case, the maximum data write voltage by the pp power supply 31, the vpp application time by the Vpp timer 32, the maximum allowable data write current by the Ipp limiter 33, etc. are set based on the answer-to-reset data stored in the initial parameter RAM 16. be done.

An IC card operating frequency selector 34 is connected to the data transmission line 16a. An oscillation signal from an oscillator 35 is supplied to this selector 34 via a frequency divider 36.
It is output from the CI ock terminal as a signal with the operating frequency set.

The system control line 17a of the main controller 17 includes a comparator 21, an IPK (Issuer's Pu
blic KeV) ROM 41 and the like are connected, and control commands are sent from the main controller 17 to each circuit depending on the operating state of the system.

The display drive controller 18 controls the display on the display section 3 of the terminal 1.

The key controller 19 provides a key sampling signal to the keyboard 2 of the terminal 1 to detect a key input signal.

The reader/writer controller 20 drives and controls the reader/writer start-up section 38. Here, the mechanism section 38 is equipped with a card transport motor, and transports the IC card 5 inserted from the card insertion slot of the terminal 1 to a predetermined position, electrically connects the card 5 to the terminal 1, and When the processing is completed, the IC card 5 is returned to the card insertion slot.

In such a reader/writer mechanism section 38, an output buffer 7 is provided.
24. Reset controller 39.1pp level latch section 30. An operating frequency selector 34 and a VCCIt source 40 are connected. These output buffer 24, reset controller 39, pp level latch section 30. It has an I10 terminal, a Re5et terminal, a vpp terminal, a Clock terminal, and a VCc terminal connected to the IC card 5 side in correspondence with the operating frequency selector 34 and the Vcc power supply 40, respectively.

The input controller 26 and the output controller 23 control data exchange with the C card 5 in response to commands from the main controller 17 via the initial parameter RAM 16. Among these, the input controller 26 outputs the data sent from the IC card 5 to the working RAM 13 etc. via the input buffer 25 and also provides it to the comparator 21, and provides the comparison output here to the main controller 17. Further, the output controller 23 sends data provided from the terminal ROM 15 or the like to the IC card 5 via the output buffer 24.

rR8A] The encryption unit 22 is the working RAM 13
The rPANJ sent from the IPKROM 41 is encrypted according to the public key code given from the IPKROM 41. The IPK ROM 41 contains the decryption code rP written in the data memory of the IC card 5.
RKJ (Private Key Code) A corresponding public key code is written in advance, and the stored code is output according to a command from the main controller 17.

Next, FIG. 2 shows the circuit configuration of the IC card 5. As shown in FIG. In the figure, 51 is a system bus, and this system bus 51 has an answer-to-reset data ROM 5.
2. Application ROM53, test program R
oM 54, system program ROM 55, working RAM 56, central controller 57, storage memory read/write controller 58, decryptor 59
, a random number generator 68, an input controller 61 via an input buffer 60, and an output controller 63 via an output buffer 62 are connected, respectively. Further, a data input/output terminal I10 is connected to the input controller 61 and the output controller 63.

Here, the answer-to-reset data ROM 52 is
It stores all operating conditions for the C card 5 itself (for example, data input, applied voltage, current permissible value and maximum applied voltage, maximum data transmission amount, maximum response waiting time, etc.), and these condition data are stored inside the card itself. When the initialization is completed, it is transmitted to the terminal 1 side as answer-to-reset data in accordance with a predetermined format.

The application ROM 53 stores card type data rAPNJ indicating what type of IC card 5 this card type data is.
After setting the initial parameters based on the two-reset data, the data is sent in a predetermined format when exchanging attributes with the terminal 1 side.

The test program ROM 54 stores a program for card testing.

The system program ROM 55 contains various system programs as well as code signals rAcKJ or rNA indicating whether the signals transmitted and supplied from the terminal 1 side are correct or not.
Equipped with CJ.

The working RAM 56 stores various processing data within the card, and also has a counter 561 that counts the number of consecutive offline uses.

The central controller 57 outputs operation commands to each circuit according to the data reception signal transmitted and supplied via the input buffer 60 and the operation state.

The storage memory read/write controller 58 controls the writing and reading of data to and from the storage memory 64 in response to commands from the central controller 57.

In this case, the storage memory 64 includes a zone address table 641, a public zone 64 as shown in FIG.
2, a secret zone 643, a transaction zone 644, and a credit zone 645. Here, the zone address table 641 stores a predetermined zone address as test data used for card authentication, for example, and extracts verification data from a predetermined zone based on the address, and also extracts verification data from a predetermined zone by comparing it with the test data. Card authentication is now performed. Public zone 642 stores public data. The secret zone 643 is, for example, a password r.
PINJ, data re-input count rRTNJ (Re-
Try Number), PIN number rlPINJ (Initia
lzationPersonal Identification
account number), account number rPANJ
(Primary Account Number
r), decryption code rPRKJ (Privat
eKey Code) etc. are stored. Also,
This secret zone 643 stores secret information regarding the cardholder.

The transaction zone 644 stores various data related to general transactions, and as shown in FIG. 5, has transaction data areas 644a #1 to #n that store data for each transaction unit. Here, each transaction data area 644a includes 2-byte year and month data representing the year and month of the transaction, rOFF Line
It is in use, but it is being transferred via ON Line.
Did the customer see the details of the transaction? "On/offline transaction"
1 byte of status data representing various states such as 1 byte of status data representing the current day, 1 byte of format data representing the type of transaction format, 1 byte of SIC data representing the company code, 1 byte representing the terminal application card number TAN data of , 1 byte of currency unit data representing the currency unit, 6 bytes of amount data representing the transaction amount, 2 bytes of TAC data representing the transaction completion number, and 6 bytes of remaining data representing the credit balance are stored. There is. Credit zone 245 stores data regarding credit transactions.

Returning to FIG. 2, the random number generator 68 generates random numbers according to instructions from the central controller 57.

The decryptor 59 decrypts the code based on a predetermined algorithm, and uses the decryption code rPRKJ from the storage memory 64 to decode the input data supplied from the terminal 1 side via the manual buffer 60. It looks like this.

The contents of the storage memory 64 successively read by the storage memory read/write controller 58 are applied to one input terminal of the comparator 66 . The comparator 66 has input data decrypted by the decryptor 59 and working R at the other input terminal.
Data stored in the AM 56, a specific code stored in the data ROM 52, etc. are provided. The comparison output of this comparator 66 is then sent to the central controller 57.

When the IC card 5 thus constructed is attached to the terminal 1 (not shown), the reset signal Re5et1 system clock clock is supplied from the terminal 1 side, and the vCC power source and the Vpp power source are connected. Here, vcciii is a power supply for driving the system, Vpp power supply is a power supply for writing to the storage memory 64,
The power supply voltage is set on the terminal 1 side based on answer-to-reset data stored in the data ROM 52. On the other hand, a system operation signal from the system clock is supplied to each circuit via a frequency divider 67.

Next, the operation of the embodiment configured as described above will be explained.

In this case, offline card usage will be explained.

First, a brief explanation will be given of the steps from mounting the IC card 5 to the terminal to inputting the personal identification number rPINJ in this state. In this case, put 1c card 5 in terminal 1! !
Then, an initial setting signal set in advance on the terminal 1 side is transmitted.

Then, depending on the operating conditions based on this signal, the IC card 5
is operated. In other words, the answer data stored in the data ROM 52 under the control of the central controller 57
Two-reset data is successively output and sent to terminal 1 from the I/O'M child via the output controller 63.

In this way, when the answer-to-reset data is sent to terminal 1, the terminal 1 side transfers the sent data to input controller 26 and input buffer 25.
The initial parameter is written to the RAM 16 via the . Then, the main controller 17 determines whether the answer-to-φ reset data written in the initial parameter RAM 16 is correct for the terminal 1. Here, if it is determined to be compatible,
The main controller and controller 17 control the data loading voltage of the Vpp power supply 31, the data loading continuous application time of the Vpp timer 32, the allowable value of the data writing current of the Ipp limiter 33, and the operating frequency of the operation selector 34, respectively, as answer-to-reset data. Based on the card-specific operating conditions. From this state, in response to a command from the main controller 17, the rEN
The QJ coat is taken out, and this is the output controller 23,
It is transmitted to the IC card 5 via the output buffer 24.

On the IC card 5 side, this code is stored in the working RAM
Add 2 to 56. In this state, the central controller 57 determines whether or not the r EN Q J code can be properly received in normal operation, and if YES from the system program ROM 55, the r ACKJ, N
In the case of o, the rNAcJ (7) signals are respectively taken out and sent to the terminal 1 side via the output buffer 762 and the output controller 63.

In terminal 1, this judgment result is stored in working RAM 1.
Write in 3. Then, when the rAcKj signal is confirmed,
Terminal attribute ROM1 by main controller 17
A different terminal code rTCJ is taken out according to the type of terminal 1 stored in the terminal 5 and latched into the output buffer 24.

On the other hand, when the rNAcJ signal is confirmed, the connection with the IC card 5 in the reader/writer system section 38 is severed.

The terminal code rTc is latched in the output buffer 24.
When J is sent to the IC card 5, the central controller 57 in the IC card 5 stores it in the application ROM 5.
A different application name rAPNJ is extracted depending on the type of card stored in the terminal 3, is latched once in the output buffer 62, and then sent back to the terminal 1 side.

On the terminal 1 side, rAPNJ is used as working RAM13.
After storing it in the rAP, the main controller 17
NJ is taken out, and it is determined whether or not there is a correspondence between rAPNJ stored in the terminal attribute ROM 15 and its usage type. If the type matches that of the IC card 5, the instruction code is extracted from the system program ROM 14 and sent back to the IC card 5. On the other hand, if they do not match, the connection with the IC card 5 at the reader/writer mechanism section 38 is severed.

After waiting for such an instruction code, the user is allowed to input his own personal identification number rPINJ from the terminal 1.

In this state, from keyboard 2 of terminal 1, a
ll When the identification number rPINJ is input, this rPINJ
IG card 5+7) I10 terminal input controller 61, working RAM 5 via input buffer 760
6 and then provided to a comparator 66.

In this state, step A of the flowchart shown in FIG.
Go to 1. In step A1, after the central controller 57 determines whether rPINJ is input,
The storage memory read/write controller 58 is commanded to read the password rPIN-J written in advance in the secret zone 643 of the storage memory 64, and the read password rPINi is provided to the comparator 66. Then, the personal identification number rPINJ input from the terminal 1 is compared with the personal identification number rPINJ.

In this case, based on the comparison results between the two, the identity verification and the card verification are performed, and then the process proceeds to the actual card transaction processing shown in step A2.

In this step A2, transaction data corresponding to the current card transaction input from the keyboard 2 of the terminal 1 is sent to the IC card 5 side via the output controller 23 and the output buffer 24, and the input controller 63 of the IC card 5 , working RAM via input buffer 62
56.

In this state, proceed to step A3. In this step A3, the previous transaction area 644a in the transaction zone 644 of the storage memory 64, here #Ti, is
transaction area 644a. Then, in step A4, after clearing the contents of the counter 561 of the working RAM 56 to "0", the process proceeds to step A5, and it is determined whether there is data in the corresponding transaction area 644a of #T1. In this case, if there is data and the answer is YES, the process advances to step A6. and,
In this step A6, it is determined whether the transaction data in the transaction area 644a of #Ti is for offline use. Here, if it is determined that it is for offline use, the process proceeds to step A7, and the working RA
The contents of the counter 561 of M56 are counted up by "+1", and the process proceeds to step 88, where #T
Transaction area 6 of #T+-1 one place before i
44a. Then, returning to step A5, it is determined whether there is data in the corresponding transaction area 644a of #Ti-1, and then in step 86, the transaction data in the transaction area 644a of #T+-1 is offline. Determine whether it is used.

In this case as well, if both are determined to be YES, the operations from step A5 to step 88 are repeated in the same way, and in step A7 the contents of the counter 561 are counted up by "+1" until #T1- Similar operations are performed for the second and subsequent transaction areas 644a.

In this state, if it is determined in step A5 that there is no data, or if it is determined in step 80 that the data is not used offline, the process advances to step A9.

In this step A9, it is determined whether the contents of the counter 561 of the working RAM 56 are within a predetermined value range. That is, in step A9, the number of consecutive uses in offline transactions is checked. In this case, if the transaction is to be concluded unconditionally from 1st to 4th time, working R
If the content of the counter 561 of the AM 56 is in the range of "○J" to "4", the process proceeds to step AIO with YES, and the #T of the transaction zone 644 of the storage memory 64 is
The current transaction data is written to the i+1 transaction area 644a, and the process ends.

On the other hand, in step A9, if it is determined that the content of the counter 561 has exceeded "4" and the result is No, step A1
Go to 1. In step A11, the number of consecutive uses in offline transactions is checked again. In this case, 5 to 1
Assuming that the transaction is conditionally concluded up to 8 times,
The content of the counter 561 of the working RAM 56 is “5”
~ “18”, YES and step A12
Proceed to.

In this step A12, the central controller 57
The random number generator 68 generates random numbers according to the command. Then, the content of the random number at this time is compared with the numerical value n. In this case, the number n consists of a plurality of numbers that match a random number with a certain probability, and is stored in the system program ROM in advance.
55, etc.

Here, if both match, select YES and step 1
Proceeding to step o, the current transaction data is written to the #T++1 transaction area 644a of the transaction zone 644 of the storage memory 64 in the same manner as described above, and the process ends.

On the other hand, in step A12, if the random number generated by the random number generator 68 and the preset numerical value n do not match, the process proceeds to step A13.

In step A13, a command prohibiting transactions is sent to the terminal 1 via the output buffer 762 and output controller 63 on the IC card 5 side.

At terminal 1, this command is input to controller 26,
It is written into the working RAM 13 via the input buffer 25, and at the same time, a message indicating that the transaction is not allowed is displayed on the display section 3 via the display drive controller 18 according to a command from the main controller 17.

Then, in step A14, from terminal 1
Card 5 is forcibly ejected.

Further, if it is determined in step A11 that the number of consecutive offline transactions has exceeded 18, in this case, the process unconditionally proceeds to step A13, and the
A message indicating that transactions are not possible will be displayed. Then, in step A14, the IC card 5 is forcibly ejected from the terminal 1.

Note that in the above description, the contents of the counter 561 range from "5" to "1".
8", offline transactions are permitted with a certain probability based on the random number value of the random number generator 68. On the other hand, if offline transactions are not permitted, a message to that effect is displayed on the terminal 1, and the terminal Card 5 is ejected from Terminal 1, but if it is rejected, it will be written in the current transaction data and a notification will be sent to Terminal 1 that the next offline transaction will be rejected. After displaying this to alert the cardholder, the current transaction data may be written to the #T1TiO2 transaction area 644a of the transaction zone 644 of the storage memory 64, and the transaction processing may be completed.

Therefore, if you do this, the transaction will be unconditionally completed until the number of consecutive offline uses is 4, and if it exceeds 4, the random number generator 68 will generate a random number, and the value of this random number will determine the It is now possible to allow offline transactions with a probability, and the number of consecutive offline transactions is 5 to 1.
Since the setting can be set to an indeterminate value within the range of 8 times, even if an attempt is made to fraudulently use the card by using offline continuously, this number cannot be specified, so this attempt can be deterred, and offline In addition to preventing unauthorized transactions, it is also possible to improve safety when used offline.

In addition, by setting a limit on the number of consecutive offline uses, it becomes possible to make any number of transactions within the limit seen in conventional offline methods that set the transaction amount per transaction. Such inconveniences can be eliminated, and crimes caused by such methods can be completely eliminated.

Note that the present invention is not limited to the above-mentioned embodiments, but can be implemented with appropriate modifications without changing the gist. for example,
The number of times a transaction is established unconditionally and the number of times a transaction is conditionally established in the embodiment described above are merely examples, and may be set to other times.

[Effects of the Invention] According to the inventions of and -, by making the number of consecutive offline uses indeterminate within a predetermined number of times, fraudulent transactions due to continuous offline use can be prevented, and safety can be improved. can be achieved.

[Brief explanation of drawings]

Figure 1 is a block diagram showing the circuit configuration of a terminal used in one embodiment of the present invention, Figure 2 is a block diagram showing the circuit configuration of an IC card in the same embodiment, and Figure 3 is used in the same embodiment. Diagram for explaining storage memory, 4th
The figure is a diagram for explaining the transaction zone of the same storage memory, and FIG. 5 is a flowchart for explaining the operation of the same embodiment. DESCRIPTION OF SYMBOLS 1... Terminal, 2... Keyboard, 3... Display unit, 5... IC card, 17... Main controller, 56... Working RAM, 561... Counter, 57... Central controller, 64...
Storage memory, 643...Secret zone,
644...Transaction zone, 644a...
Transaction area, 66... Comparator, 68...
・Random number generator. Source: Kajio Computer Co., Ltd. Mochi Figure 3 Figure 4 Figure 5 Figure 92 Procedural Amendment 1, Case Indication Patent Application No. 140635/1982 2, Name of Invention IC Card System 3, Person Making Amendment Case and Relationship between patent applicant 2-6-1-5 Nishi-Shinjuku, Shinjuku-ku, Tokyo, 1, 2, and 2 in the drawings subject to amendment Figure 5

Claims (2)

[Claims] (1) In an IC card system having an IC card and a terminal to which the card is installed, there is a counting means for counting the number of offline uses of the IC card, and a count value of the counting means exceeds a first set value. An IC card system characterized by comprising means for disabling offline use of the card when the card is used. (2) A random number generating means, and if the counted value of the counting means exceeds a second set value that is less than the first set value and is less than or equal to the first set value, the random number is generated by the random number generating means. 2. The IC card system according to claim 1, further comprising means for permitting current offline use with a predetermined probability based on a random number.