JPS61262889A - Card writing device - Google Patents

Abstract

PURPOSE:To prevent unjust use by giving two kinds of confirmation patterns to an IC card and rewriting them every time it is used. CONSTITUTION:When an IC card 104 is inserted, a random number is generated by a random number generator 110, and the card is sent as the first confirmation pattern. The random number is encoded by a key K1 and stored in a RAM 109 as a confirmation pattern. The IC card 104 encode the first confirmation pattern by the key K1 and compares with a confirmation pattern stored in the RAM 109 and judges its correctness. The IC card makes the second confirmation pattern by random numbers to confirm the terminal and sends to the terminal, and encodes by a key K2 and sends back as the second answer pattern. Then, the IC card examines whether it coincides with the pattern made by encoding the second confirmation pattern by the K2, and judges correctness of the terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a card writing device, and more particularly to a data writing device for a card with an arithmetic function used for monetary data transactions.

(Prior Art and Problems) Conventional data writing devices use magnetic cards and punch cards for exchanging monetary data, but these cards have the disadvantage of being easily copied. Recently, a card with an arithmetic function (hereinafter referred to as an IC card) has been developed as a data writing device, and a card authentication method using the card has been proposed. For example, the IEEE S
pectrum) February 1984 issue, pages 43 to 49, describes a method in which personal identification numbers are stored in an area that cannot be accessed from the outside, and the user inputs the personal identification numbers to determine whether they match. is listed. However, if input information is recorded on an IC card by a card writing device using these methods and is later played back, there is a drawback that fraud cannot be prevented.

(Object of the Invention) An object of the present invention is to provide a card writing device which eliminates the drawbacks of conventional card writing devices and which makes it impossible to copy cards or write unauthorized data onto cards.

(Structure of the Invention) According to the present invention, in a card writing device that detects unauthorized access to a card, a predetermined first
storage means for storing a code and a second code; and pattern generation means for sending a first authentication pattern to the card;
a first authentication pattern for the first authentication pattern from the card;
determination means for determining whether or not the response pattern of the first authentication data, the first code, and the first authentication butter/are in a predetermined relationship; A card writing device is obtained, characterized in that it consists of pattern conversion means for converting the code into a pattern that is returned to the card depending on the code.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

Figure 41 shows an embodiment of the present invention. In FIG. 1, an example M16 of the present invention is a card writing device that detects all unauthorized accesses to and from a card. A keyboard interface 105, a display 106, a read-only memory (RORi) 108, and a random access memory (RA) are connected to each other.
M)109. Random number generator 110 Hand-crafted cipher/decoder 11
1, the keyboard 105 connected to the keyboard interface 105, and the spring 120Vc connected Sarekatsu IC
Card interface 10 connected to card 104
7.

A microprocessor 101 controls the entire device, and a keyboard 102 and keyboard interface 105 are used to input data to be written to the IC card. The display 106rJ is for displaying input data and notifications when the IC card is fraudulent. The IC card 104 is a partner card to which the device of this embodiment attempts to write data, and is connected to the card interface 107 (c
It is configured to send and receive data through. 13,
0M108 contains programs for the microprocessor 101 and code for the encoder/decoder! Toni 2 (hereinafter referred to as key 1° and key 2 are stored and constitute a storage means. The encoder/decoder 111 is used for encoding/decoding used in the authentication process, and is included in the butter 7 conversion means for converting into a response pattern to be sent back to the card. Reference numeral 101 includes means for determining whether or not the first response pattern and the first authentication pattern have a predetermined relationship.

FIG. 2 shows the microprocessor 101 in this embodiment.
A flowchart of the work to be done is shown.

In FIG. 2 (al), in this embodiment, when the IC card 104 is inserted and contacted, the random number generator 110 generates a random number and sends it to the IC card as the first authentication pattern. Encrypt it with ! and store it in the AM109 as a verification pattern.

The IC card 104 is used as all keys for this first authentication pattern!
is encrypted and sent back to the microprocessor 101 as the first response pattern. The microprocessor 101 receives the first data from the IC card 104 as shown in FIG.
It is determined whether the IC card is the correct card or not based on whether the response butter 7 is equal to the verification pattern stored in the RAM 109. If it is correct, the microprocessor 101 requests the IC card 104 to write the data, and if it is incorrect, the notification is displayed on the display 106.

On the other hand, since there is a risk that all data on an IC card may be written to an unauthorized card terminal (card writing device) without permission, the terminal will be authenticated. In other words, IC car) "104H
As shown in Figure i2 (C), a second authentication pattern is created using random numbers and sent, but the microprocessor 101 encrypts it using 2 as a key and sends it back as a second response pattern. Ic Card = Go - 104iJ It is determined whether the card terminal is the correct terminal based on whether the pattern encrypted with 2 using this second authentication pattern as a key matches the second response pattern. In order for all judgments to function properly, please set the key to 1. It is necessary to keep it a secret.

In this way, in this embodiment, the previous exchange between the IC card and the card writing device is recorded, and even if it is played back later, the authentication pattern will have changed depending on the card used, so unauthorized use can be prevented. It can be prevented.

The crypto+i-/decoder 111 can use, for example, the American Data Encryption Standard (DBS). Random number generator 110
Is it a natural random number? Although it is preferable to generate the number, a pseudo-random number generator may also be used. Further, the microprocessor 101 can be used as both or one of the encoder/decoder and the random number generator to perform software.

(Effects of the Invention) As explained above, the present invention makes it difficult to copy cards or illegally write data on cards, and has an extremely significant effect when applied to financial data transactions, etc. .

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the disaster of the present invention,
FIG. 2 is a flowchart showing the working process of the microprocessor 101 in this embodiment. 101...Microprocessor, 102109.
Keyboard, 104...IC card, 105.
...Keyboard interface, 106...
・Display, 107... Card interface, 108...R (JM, 109...
・l(, AM, 110...Random number generator, 111
...Encryptor/decryptor.

Claims (1)

[Claims] A card writing device for detecting unauthorized access between cards, comprising: a storage means for storing a first code and a second code determined in advance; and a first authentication pattern on the card. a pattern generating means for transmitting a first authentication pattern for the first authentication pattern from the card;
determining means for determining whether or not the response pattern of the first code and the first authentication pattern are in a predetermined relationship;
A card writing device comprising: pattern converting means for converting the code into a pattern to be sent back to the card depending on the code.