JP2000194537A - Method and device for generating physical random number - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate random number which have small correlation with adjacent random numbers fast and to facilitate the inspection of the normal operation of a random number generation source. SOLUTION: In this physical random number generating method, a chaos generating circuit 110 is used as the random number generation source, its output is converted into a digital random number through an A/D converting circuit, data is compressed by a data compressing circuit 130, and the correlation between data is eliminated. The random number is generated fast by reading a necessary number of bits of the compressed data. The inspection is facilitated by judging the chaos of the output of the A/D converting circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for generating a physical random number using chaos, and more particularly to a method and an apparatus for generating a random number which are easy to inspect and can generate a high-speed random number.

[0002]

2. Description of the Related Art Conventionally, it has been known to use a physical random number as a random number generation method based on thermal noise and radiation elements. FIG. 2 is a functional block diagram showing a basic configuration of a conventional physical random number generation device based on thermal noise. In the figure, an amplification circuit 210 amplifies thermal noise inside the circuit,
The obtained signal is output as a random number of an analog value. A /
Each time a clock pulse is supplied from the input terminal 251, the D conversion circuit 220 converts the analog value random number output from the amplifier circuit 210 into bit data of a digital signal, and outputs the bit data obtained by the conversion. . The shift register 230 is an m-stage shift register. Each time a clock pulse is supplied from the input terminal 251, the shift register 230 shifts the stored m bits to the right (the rightmost bit is discarded), and The output of the A / D conversion circuit 220 is stored at the left end. The exclusive OR circuit 240 calculates the exclusive OR of m bits stored in the shift register 230 and outputs the calculation result from the output terminal 254 as a random number.

If the number m of stages of the shift register 230 is increased, "0" and "1" are output from the output terminal 254 even if the A / D conversion circuit 220 does not output "0" and "1" with equal probability.
Is output with equal probability. The conventional physical random number generator is described in detail in, for example, "Introduction to Cryptography Theory" by Eiji Okamoto (Kyoritsu Shuppan, 1993).

[0004]

In the conventional physical random number generation device, a clock pulse is used to eliminate a correlation between a random number output at a certain time and a next time (note: time measured by the clock pulse). There is a problem that it is necessary to make the input interval of the input sufficiently long. For this reason, the conventional physical random number generation device could not generate random numbers at high speed.

Further, in the conventional physical random number generation device, there is a problem that it is difficult to check whether the amplifier circuit 210 is operating normally. This is A /
This is because various tests must be performed to test that the random number data output from the D conversion circuit 220 is a random number.

An object of the present invention is to provide a method and apparatus for generating a physical random number which can generate a random number having a small correlation between adjacent random number data at a high speed and simplify the inspection of a normal operation of a random number generation source and the like. Is to do.

[0007]

According to the physical random number generation method of the present invention, a chaos generation circuit is used as a random number generation source, and the output of the chaos generation circuit is subjected to A / D conversion to obtain a digital random number. Data compression to eliminate the correlation between data, read out the required number of bits of each compressed data, generate random numbers, and enable the inspection of the random number generation source by judging the chaos of the output of the A / D conversion circuit. It is characterized by.

A physical random number generation device according to the present invention includes a chaos generation circuit for outputting a random number of an analog value generated based on chaos, and an A / A converter for converting the random number of the analog value output from the chaos generation circuit into a digital value. A D conversion circuit, a data compression circuit that performs data compression on a series of digital random numbers output by the A / D conversion circuit and outputs compressed data, and stores compressed data output by the data compression circuit. And a buffer for sequentially reading out a predetermined number of bits from data accumulated every time a clock pulse is input and outputting the same as a random number. Further, the data compression circuit performs data compression by converting the data into a reversible code such as a Huffman code or an arithmetic code.

Specifically, a chaos generation circuit (11) for outputting a random number of an analog value generated based on chaos.
0) and an A / D conversion circuit (1) that converts a random number of an analog value output from the chaos generation circuit (110) into a digital value.
20), a data compression circuit (130) for performing data compression on a digital value random number sequence output from the A / D conversion circuit (120) and outputting compressed data, and an output from the data compression circuit (130). A buffer (140) for accumulating compressed data to be extracted and extracting and outputting a predetermined number of bits from the accumulated data each time one clock pulse is input from the input terminal (151);
Each time a clock pulse is supplied from the input terminal (151), the output of the buffer is output as a random number from the output terminal (154).

(Operation) By using the chaos generation circuit as the random number generation source, the normal operation of the random number generation source is simplified by utilizing the correlation of the chaos, and the A / D conversion data of the output of the chaos generation circuit is used. The data compression described above is performed to eliminate the correlation, and the required number of bits of the compressed data is read out, thereby making it possible to generate random numbers at high speed.

[0011]

FIG. 1 is a functional block diagram showing a basic configuration of an embodiment of the present invention. In the figure,
The chaos generation circuit 110 generates and outputs a random number of an analog value based on chaos using a non-linear circuit or the like. A
Each time a clock pulse is supplied from the input terminal 151, the / D conversion circuit 120 converts a random number of an analog value output from the chaos generation circuit 110 into a digital value and converts the random number into, for example, a binary digital value. Output random number.

The data compression circuit 130 performs a lossless data compression on the sequence of digital random numbers output from the A / D conversion circuit 120 by performing a reversible data conversion defined by Huffman code or arithmetic code. And outputs the generated compressed data every time a clock pulse is supplied from the input terminal 151.

Each time a clock pulse is supplied from the input terminal 151, the buffer 140
The compressed data output by 0 is stored, a predetermined number of bits are sequentially extracted from the stored data and output, and the output of the buffer is output from the output terminal 154 as a random number.

The output of the A / D conversion circuit 120 is also output from an output terminal 152 for inspection. Also, the buffer 140 may store the compressed data with a smaller number of bits than the predetermined number of bits output as a random number. In this case, a signal indicating the shortage of the number of bits is output from the output terminal 153. "0" is output, and when the number of bits of the stored compressed data is equal to or larger than a predetermined number of bits, "1" is output from the output terminal 153.

The physical random number generation apparatus according to the present embodiment can eliminate data redundancy by distortionless data compression. When "1" is output from the output terminal 153, one clock pulse is generated. Each time it is input, a random number is output from the output terminal 154. However, the output terminal 153
If "0" is output from the
Is smaller than the data amount to be output as a random number. Therefore, when “0” is output from the output terminal 153, the user of the physical random number generation device supplies a clock pulse to the input terminal 151 until “1” is output from the output terminal 153, and , The data output from the output terminal 154 is not used as a random number.

When the physical random number generation device is mass-produced, the output terminal 152 for inspection is used in the inspection process in the manufacturing process to check whether or not the output data series is chaos. If the data series output from the output terminal 152 is not chaotic, the manufactured physical random number generation device is processed as a defective product.

[0017]

According to the conventional physical random number generator, various tests need to be performed to determine whether or not the random number sequence is a random number. According to the present invention, however, the data is output from the output terminal. By checking whether or not the data series is chaos, it is possible to check whether or not the chaos generation circuit is functioning normally, so that the device can be easily checked.

Further, in the conventional physical random number generation device, in order to eliminate a correlation between a random number output at a certain time and a next time (note: a time measured by a clock pulse), an interval for inputting a clock pulse is used. However, in the present invention, the data compression circuit performs distortion-free data compression to eliminate data redundancy between random numbers, and removes correlation, thereby increasing the sample interval. This eliminates the need to perform this operation, and it is possible to generate random numbers at high speed.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a physical random number generation method and device of the present invention.

FIG. 2 is a diagram showing a conventional random number generation device.

[Explanation of symbols]

 110 Chaos generation circuit 120, 220 A / D conversion circuit 130 Data compression circuit 140 Buffer 151, 251 Clock input terminal 154, 254 Random number output terminal 153 Output terminal 210 Amplification circuit 230 Shift register 240 Exclusive logic circuit

Claims (4)

[Claims] 1. A chaos generation circuit that generates a random number of an analog value is used as a random number generation source, A / D conversion of an output of the chaos generation circuit is performed to obtain a digital random number, and data compression of the digital random number is performed. It eliminates the correlation between data, generates the random number by reading the required number of bits from each compressed data, and enables the inspection of the random number generation source by judging the chaos of the output of the A / D conversion circuit. A physical random number generation method. 2. A chaos generation circuit that outputs a random number of an analog value generated based on chaos, an A / D conversion circuit that converts a random number of an analog value output from the chaos generation circuit into a digital value, A data compression circuit for performing data compression on a series of digital random numbers output from the / D conversion circuit and outputting compressed data; storing compressed data output from the data compression circuit; And a buffer for sequentially reading a predetermined number of bits from the data and outputting the number as a random number. 3. The physical random number generation device according to claim 2, wherein said data compression circuit performs data compression by conversion into a code capable of reversible conversion. 4. The physical random number generation device according to claim 3, wherein a Huffman code or an arithmetic code is used as the reversible transformable code.