KR20000066708A - Ic card being applied chaos ciphering method - Google Patents

Abstract

PURPOSE: An IC card adopting a chaos coding method is provided to input an instruction set at a ROM for executing an exclusive chaos coding process and input tabled chaos time series and coding keys at an EEPROM to control a time element and enhance a data search speed. CONSTITUTION: An IC card adopting a chaos coding method comprises a CPU(Central Processing Unit, 1), a ROM(2), an EEPROM(3), and a main body(4). The CPU(1) has a general numerical calculation and logic operation function. The ROM(2) stores an instruction set. The EEPROM(3) stores nonlinear quantized time series at a database, and coding keys. The coding data is stored at a user computer as a file. The CPU(1) receives divided blocks of the coding data file via an input port(5), searches a coding code from the database, and transmits the code via an output port(6).

Description

IC card with Chaos encryption method {IC CARD BEING APPLIED CHAOS CIPHERING METHOD}

The present invention relates to an IC card employing a chaotic encryption method that can more easily and securely manage personal information in an information and communication network, which is a main component of computer and communication.

In today's telecommunications network, a major component of computers and communications, information needs to be securely managed at various levels. Passwords are used as a means of safety management.

It is a collective security management method to have a cryptographic restoration function on a server in a network.

In a personal terminal, each user manages information securely at his own risk.

Non-linear quantization of time series that can observe chaos, digital block divided into reduced quantum correspond to encryption key, search and encryption restoration method of time series, and encryption restoration method using chaos order is well known. will be.

Chaos generation can be done through electronic circuits or by nonlinear mapping functions obtained by a precision calculation method.

Although nonlinear quantization can be done circuitally using a nonlinear analog-to-digital converter (ADC), the time series can be stored in memory in the calculator and then quantized by nonlinear division.

The unique feature of chaos cryptography is that if the same encryption is required, different encryption cards are always generated even if the same encryption key is used when the digital file is repeatedly encrypted.

Chaos cryptography has been provided in software. Thus, managing information securely is now managing software securely. The software can be easily copied by anyone. Even downloaded downloads can be copied.

Accordingly, the present invention has been made to improve such a problem, and an object of the present invention is to provide an encryption restoration system with hardware of an IC card in order to escape from the above-mentioned risk.

The present invention for achieving the above object is characterized in that the central processing unit has a search function and has a database of instruction sets and a chaotic time series in a storage device (memory).

1 is a block diagram of an IC card for restoring encryption.

Explanation of symbols on the main parts of the drawings

1 ---- CPU 2 ------ ROM

3 ---- YPIROM 4 ------ IC card body

5 ---- input 6 ------ output

Some IC cards are equipped with a central processing unit (CPU) even though they are small in size. The instruction set for dedicated processing is entered in the ROM. The database and encryption key of the Chaos Time series are entered in EEPROM.

If the time series that evenly reduces the quantum size of the reduced quantum generated by the nonlinear quantization is input into the ypyrom as it is, the amount of data becomes huge.

When performing a search for encryption, for example, in the time series quantized to 8-bit 256 quantum, the encryption code is the value y (t-4) from the 4-step past for the data y (t) searched and found. . By tabulating the time elements, the search can be run quickly and the time series data can be compressed. You can also design the search differently so that you can search tables except time elements. For example, when quantized to 8 bits, the table is 16 rows and 16 columns. The way to arrange the rows is the encryption key.

In the Chaos Time series, fractal properties are preserved. The characteristics of the chaotic ciphers, which generate different cipher codes when repeatedly encrypted by inputting data of a certain range of the time series into the YEPROM as a search database, do not disappear.

An example of the IC card configuration is shown in FIG. 1 is a central processing unit with a search function. All you need is general mathematical and logical computing capabilities. The necessary command code set is entered in the ROM 2. The chaotic time series nonlinearly quantized with Y pyrom 3 is stored in a database table. At the same time, an encryption key is also set.

The data to be encrypted is stored in a personal terminal memory as a file. A divided block of digital files to be encrypted is sent from the input (5) to the register of the central processing unit (1) and, upon command, the central processing unit (1) searches the database 3, finds the encryption code and outputs it (6). Transfer from This is the encryption process.

Restoration is the reverse process of encryption. The database 3 can be executed even if it is common, but the database 3 of the encryption is used to leave a predictable characteristic of the chaos in the encryption code by using a table that has left a time element, and the time 3 is not necessary for the database 3 to be restored. Different IC cards 4 may be used for encryption and restoration.

(Example)

1 illustrates a case where a digital file to be encrypted is divided into 4-bit blocks. One of the four bit block codes, for example 0100, is assumed to have been sent to the central processing unit 1.

In Database 3, an 8-bit time series with 16 types of reduced quantums was installed without the time elements. The table matrix at the top of the input code 0100 is searched according to the encryption key arrangement, and one 8-bit encryption code is selected according to the command instruction of the ROM 2. If the code is an 8-bit code such as 10100101, the input code 0100 is replaced with an encryption code of 8-bit 10100101. At output 6 a cryptographic code 10100101 is sent. This process is repeated to convert all the information in the digital file that needs to be encrypted into a password file.

A combination of 16 types of four 4-bit input codes corresponding to 16 types of reduced numbers is an encryption key. There are 16! = 2.09 × 10 types of encryption keys that can be issued. Key issuance calculates the distance and the computer automatically issues and manages keys that are far enough apart.

When restoring from the same IC card, an 8 bit encryption code is transmitted from the input (5). This can be sent by dividing the upper 4 bits and the lower 4 bits. The cipher code is retrieved on a time series database and the corresponding reduced both 4-bit code is obtained and sent at the output 6.

When the 4-bit code is encrypted with the 8-bit code and the 8-bit encryption code is restored with the 4-bit code as in this embodiment, the central processing unit 2 is a computing device such as Z-80 with an 8-bit database. do.

If the digital files to be encrypted are documents and data, the length of the digital block to be divided is appropriately 4 bits and 8 bits. On the other hand, a 5-bit block is suitable for encrypting and transmitting and restoring high-order 5 bits in order to guarantee sound quality by the analog-to-digital conversion of a speech signal such as voice. It is reasonable to design a system with 5 bits of unit blocks when encrypting and restoring voice in real time.

The IC card can be hierarchically structured by performing basic operations (shifting, rotating, inverting, replacing) in issuing an encryption key.

A feature of the cryptographic restoration system that is instrumentally structured using chaotic order is that it encrypts with the key A and then decrypts it with the key B. In this case, the wrong file is encrypted with B. Then decode in A to find the original text. This is because order is also structured.

As described above, although it is a convenient method to perform the encryption restoration process by software, it is not safe because it can be easily copied to anyone.

On the other hand, hardware management is simple compared to software. The present invention hardwareizes a chaotic cryptographic restoration system using a universal IC card equipped with a central processing unit, a ROM, and an Ipyrom.

In other words, an IC card equipped with a central processing unit, a ROM, and an EPROM can be dedicated by making the central processing unit common and inputting a unique command into the ROM's command code set and the IC's chaos database. It is a method that can cope with individualization by utilizing common hardware resources.

In addition, the encryption IC card and the restoration IC card can be integrated into one common card. Dividing into two can speed up the processing and is suitable for audio and video real-time processing.

In addition, it is a principle of the present invention to assign a unique key to the IC card, but it is also possible to hierarchically configure an encryption restoration system for a plurality of IC cards by applying a basic operation to the key configuration. As described above, the present invention proposes a new method for realizing secure management of information in an information communication network.

Claims (1)

An IC card to which a chaos encryption method is applied, wherein the central processing unit has a search function and has a set of instructions and a database of chaos time series in a storage device (memory).