Random number sequence sharing system, random number sequence sharing device, encryption/decryption system, encryption device, decryption device, random number sequence sharing method, encrypting method, decryption method, and program

The present invention includes a random number string sharing system, a random number sequence sharing device, a cryptographic decryption system, a cryptographic device, a decryption device, a random number string sharing method, a cryptographic method, a decryption method, and a computer for using the radio waves emitted from a radio star. Regarding the program realized in.

Conventionally, in the field of information and communication technology, research on authentication technology for confirming who is the creator or sender of a message has been promoted. At present, signature authentication systems and cryptographic communication systems using public key cryptography are becoming widespread.

On the other hand, VLBI (Very Long Baseline Interferometry) radio waves emitted by radio stars such as quasars and mesa radio sources (including water mesa radio sources, ammonia mesa radio sources, and methanol mesa radio sources) Attempts have also been made to receive the radio waves and use them in various technical fields. In particular, the signal received by VLBI has ideal perfect randomness, and radio waves from radio stars can be transmitted at any point on the earth (depending on the type of radio star, on the surface of the earth facing the radio star). It has the feature that it can be received at any existing point).

For this reason, a technique for measuring the relative positional relationship between a certain point and another point on the earth using VLBI is also being put into practical use.

In the field of information and communication, the inventors have already proposed an authentication system using radio wave stars, etc. in view of the demand for more secure authentication technology that can prevent "spoofing". ing.

In addition to the proposals made by the inventors, the preceding technical documents include the following.<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2003-218866</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2001-308845</text></patcit><patcit num="3"><text>Japanese Unexamined Patent Publication No. 2000-278259</text></patcit><patcit num="4"><text>Japanese Unexamined Patent Publication No. 11-243313</text></patcit>

[Patent Document 1] discloses an authentication system and the like proposed by the inventors. That is, the authentication device and the authenticated device observe radio waves from a common radio wave star at a common observation time, estimate the position of the other party from the information of the radio waves observed by each, and the estimated position and the estimated position in advance. A technique for successfully authenticating the other party when the held position matches within a predetermined error range is disclosed.

[Patent Document 2] discloses an encryption technique using a stream cipher that cannot be easily deciphered. That is, a random number sequence is generated based on the given multiple affine key, and encryption is performed by the exclusive logical sum of the random number sequence and the plaintext, and this multiple affine key is newly used every predetermined number of times. It is a technology that is automatically sequentially rewritten into a key sequence, and the rewritten multiple affine key sequence continues to encrypt the plaintext of the transition through random number generation.

[Patent Document 3] discloses a data distribution system that distributes advanced data to a specific user. That is, the encryption processing unit reads the data to be distributed stored in the data storage unit, adds the secret key read from the secret key writing processing unit to the data, and further writes the secret key to the data. Encryption processing is performed using another private key read from the processing unit, and the decryption processing unit holds the received encrypted data in the private key holding unit added to the previously received data. This is a technique for performing decryption processing using a private key that has been used.

[Patent Document 4] discloses a radio telescope technique relating to relative VLBI for measuring the position of an observed celestial body to be observed as a relative value from a reference celestial body whose position is known. That is, a radio telescope capable of relative VLBI observation, etc., tracks the celestial body according to the time of the earth, and at the same time, tracks the direction of the observed celestial body for a certain period of time, then switches the direction at high speed and tracks the celestial body for a certain period of time, and also at high speed. It is a technology to track the observed celestial body by changing the direction of direction and repeat this to carry out relative VLBI observation with one antenna.

<p> On the other hand, in the field of information communication using encryption, there is a strong demand for a technique for securely sharing a random number sequence between an encryption side and a decryption side and performing encryption / decryption using this random number sequence.</p><p> The present invention solves the above-mentioned problems, and is a random number sequence sharing system, a random number sequence sharing device, a encryption / decryption system, an encryption device, a decryption device, and a random number sequence sharing method using radio waves emitted from a radio star. , Cryptographic methods, decryption methods, and programs that realize these methods on a computer.</p>

<p> In order to achieve the above object, the following invention will be disclosed in accordance with the principle of the present invention.</p><p> The random number sequence sharing system according to the first aspect of the present invention has a plurality of random number sequence sharing devices, and each of the plurality of random number sequence sharing devices has a receiving unit, a transmitting unit, a receiving unit, an analysis unit, and a selection unit. , A sampling unit, and an output unit are provided, and are configured as follows.</p><p> First, the receiving unit receives a radio signal including a radio wave emitted from a predetermined radio star at a predetermined observation time.</p><p> On the other hand, the sending unit sends the received radio wave signal to another random number string sharing device.</p><p> Further, the reception unit receives the radio wave signal sent from the other random number sequence sharing device.</p><p> Then, the analysis unit analyzes the received radio wave signal and the received radio wave signal into a plurality of independent components.</p><p> On the other hand, of the plurality of independent components analyzed for independent components, the selection unit is deviated by the arrival time difference between the random number sequence sharing device and the other random number sequence sharing device by the arrival time of the radio waves emitted from the radio wave star. Select an independent component.</p><p> Further, the sampling unit bit-samples the average of the two selected independent components, the one that precedes in time and the one that delays by the arrival time difference, and the one that follows, with a predetermined accuracy.</p><p> Then, the output unit outputs the sampled sequence of bit samples as a random number sequence shared with the other random number sequence sharing device.</p><p> Further, in the random number sequence sharing system of the present invention, each of the plurality of random number sequence sharing devices further includes a time difference acquisition unit, and the time difference acquisition unit arranges the arrival time difference by each of the plurality of random number sequence sharing devices. It can be configured to be acquired from the location, the location of the predetermined radio star, and the predetermined observation time.</p><p> Further, in the random number sequence sharing system of the present invention, the sampling unit replaces "the average of the two selected independent components whose preceding components are delayed by the arrival time difference and those which are following". Therefore, "the preceding two selected independent components" can be configured to be bit-sampled with a predetermined accuracy.</p><p> Further, in the random number sequence sharing system of the present invention, the sampling unit replaces "the average of the two selected independent components whose preceding components are delayed by the arrival time difference and those which are following". Therefore, "the trailing one of the two selected independent components" can be configured to be bit-sampled with a predetermined accuracy.</p><p> Further, in the random number sequence sharing system of the present invention, the "average" in the sampling unit can be a weighted average.</p><p> The random number sequence sharing device according to another aspect of the present invention is the random number sequence sharing device in the above-mentioned random number sequence sharing system.</p><p> The encryption / decryption system according to another aspect of the present invention includes an encryption device sharing sampling rules and a decryption device, and is configured as follows.</p><p> That is, the encryption device and the decryption device each have a random number sequence sharing device forming the above random number sequence sharing system.</p><p> The encryption device includes a key generation unit, a reception unit, an encryption unit, and a transmission unit, and is configured as follows.</p><p> First, the key generation unit selects a sequence of random numbers output from the random number sequence sharing device of the encryption device according to the sampling rule, and uses this as a Burnham encryption key.</p><p> On the other hand, the reception unit receives information to be transmitted to the decoding device.</p><p> Further, the encryption unit uses the generated Burnham encryption key to perform Burnham encryption of the received information.</p><p> Then, the transmission unit transmits the encrypted information to the decryption device.</p><p> On the other hand, the decoding device includes a key generation unit, a reception unit, a decoding unit, and an output unit, and is configured as follows.</p><p> First, the key generation unit selects a sequence of random numbers output from the random number sequence sharing device of the decryption device according to the sampling rule, and uses this as a burnham encryption key.</p><p> On the other hand, the receiving unit receives the encrypted information transmitted from the encryption device.</p><p> Further, the decryption unit decrypts the received information by the generated Burnham encryption key.</p><p> Then, the output unit outputs the decrypted information as the information transmitted from the encryption device.</p><p> The random number string sharing device included in the encryption device and the random number sequence sharing device included in the decryption device form the above-mentioned random number sequence sharing system.</p><p> Further, in the encryption / decryption system of the present invention, both the encryption device and the decryption device are further provided with a rule reception unit, and the rule reception unit is configured to accept input of sampling rules to be shared. Can be done.</p><p> The encryption device according to another aspect of the present invention is the encryption device in the above-mentioned encryption / decryption system.</p><p> The decryption device according to another aspect of the present invention is the decryption device in the above-mentioned encryption / decryption system.</p><p> The random number sequence sharing method according to another aspect of the present invention includes a receiving process, a sending process, a receiving process, an analysis process, a selection process, a sampling process, and an output process, and is configured as follows.</p><p> First, in the receiving process, a radio signal including a radio wave emitted from a predetermined radio star is received at a predetermined observation time.</p><p> On the other hand, in the sending process, the received radio wave signal is sent to another random number string sharing device.</p><p> Further, in the reception process, the radio signal sent from the other random number sequence sharing device is received.</p><p> Then, in the analysis step, the received radio wave signal and the received radio wave signal are independently component-analyzed into a plurality of independent components.</p><p> On the other hand, in the selection step, of the plurality of independent components analyzed for independent components, two are shifted by the arrival time difference between the random number sequence sharing device and the other random number sequence sharing device by the arrival time of the radio waves emitted from the radio wave star. Select an independent component.</p><p> Further, in the sampling step, of the two selected independent components, the average of the one that precedes in time and the one that delays by the arrival time difference and the one that follows is bit-sampled with a predetermined accuracy.</p><p> Then, in the output process, the sampled bit sample sequence is output as a random number sequence shared with the other random number sequence sharing device.</p><p> Further, the random number sequence sharing method of the present invention further includes a time difference acquisition step, and in the time difference acquisition step, the arrival time difference is determined by the location where the other random number sequence sharing device is arranged and the location of the radio wave star. And, from the predetermined observation time, it can be configured to be acquired.</p><p> Further, in the random number sequence sharing method of the present invention, in the sampling step, "the average of the two selected independent components whose preceding component is delayed by the arrival time difference and the one which is delayed by the arrival time difference" is replaced. Therefore, "the preceding two selected independent components" can be configured to be bit-sampled with a predetermined accuracy.</p><p> Further, in the random number sequence sharing method of the present invention, in the sampling step, "the average of the two selected independent components whose preceding component is delayed by the arrival time difference and the one which is delayed by the arrival time difference" is replaced. Therefore, "the trailing one of the two selected independent components" can be configured to be bit-sampled with a predetermined accuracy.</p><p> The encryption method according to another aspect of the present invention includes a key generation process, a reception process, an encryption process, and a transmission process, and is configured as follows.</p><p> First, in the key generation step, a sequence is selected from the random number sequences output by the above random number sequence sharing method according to the sampling rule, and this is used as a burnham encryption key.</p><p> On the other hand, in the reception process, information to be transmitted to the decoding device is received.</p><p> Further, in the encryption process, the received information is burnam-encrypted by the generated burnham encryption key.</p><p> Then, in the transmission step, the encrypted information is transmitted to the decryption device.</p><p> Further, the encryption method of the present invention further includes a rule acceptance process, and the rule acceptance process can be configured to accept input of sampling rules to be shared.</p><p> The decoding method according to another aspect of the present invention includes a key generation step, a receiving step, a decoding step, and an output step, and is configured as follows.</p><p> That is, in the key generation step, a sequence is selected from the random number sequences output by the above random number sequence sharing method according to the sampling rule, and this is used as the Burnham encryption key.</p><p> On the other hand, in the receiving process, the encrypted information transmitted from the encryption device is received.</p><p> Further, in the decryption step, the received information is burnam-decrypted by the generated burnham encryption key.</p><p> Then, in the output process, the decrypted information is output as the information transmitted from the encryption device.</p><p> Further, the decoding method of the present invention further includes a rule acceptance process, and the rule acceptance process accepts input of sampling rules to be shared.</p><p> A program according to another aspect of the present invention causes a computer to function as the above-mentioned random number sequence sharing device, encryption device, or decryption device, and causes the computer to execute the above-mentioned random number sequence sharing method, encryption method, or decryption method. It is configured to let.</p><p> The program according to another aspect of the present invention is configured to cause the computer to function as the above-mentioned authenticated device and cause the computer to execute the above-mentioned authentication method.</p><p> A computer-readable information recording medium (including a compact disk, a flexible disk, a hard disk, a magneto-optical disk, a digital video disk, a magnetic tape, or a semiconductor memory) according to another aspect of the present invention records the above program. Configure to do.</p><p> The above information recording medium can be distributed and sold independently of the computer, and the above program itself can be distributed and sold via a computer communication network such as the Internet.</p>

<p> According to the present invention, a random number string sharing system, a random number sequence sharing device, a cryptographic decryption system, a cryptographic device, a decryption device, a random number string sharing method, a cryptographic method, a decryption method, and these are used. It is possible to provide a program realized on a computer.</p>

An embodiment of the present invention will be described below. The embodiments listed below are for illustration purposes only and do not limit the scope of the present invention. Therefore, those skilled in the art can adopt embodiments in which each or all of these elements are replaced with equivalent ones, but these embodiments are also included in the scope of the present invention. ..

In the following, first, a technique for sharing a random number sequence will be described. The random number sequence sharing system of the present embodiment is composed of a plurality of random number sequence sharing devices, and each random number sequence sharing device has a similar configuration.

FIG. 1 is a schematic diagram showing an outline configuration of a random number sequence sharing device according to the present embodiment, and FIG. 2 is a flowchart showing a control flow of a random number sequence sharing process executed by the random number sequence sharing device. .. Hereinafter, description will be made with reference to these figures.

The random number sequence sharing device 101 includes a receiving unit 102, a sending unit 103, a receiving unit 104, an analysis unit 105, a selection unit 106, a sampling unit 107, an output unit 108, and a time difference acquisition unit 109.

First, the random number sequence sharing device 101 determines which other random number sequence sharing device 101 shares the random number, and sets (the location) of the radio wave star to be used and the observation time (step S201).

The observation time may be selected as long as it is possible for both random number sequence sharing devices 101 to observe radio waves from radio stars after the current time.

As the radio wave star, a maser radio source (including a water maser radio source, an ammonia maser radio source, and a methanol maser radio source) or a quasi-star (queser) can be designated. Further, the number of radio wave stars prepared in advance is not limited to one, and may be plural. In this case, a radio wave star that can be observed at the observation time is selected from the double random number sequence sharing device 101.

As will be described later, the set radio wave star and the observation time function as one of the "seed of random numbers" when sharing the random number sequence.

Then, the receiving unit 102 receives the radio signal including the radio wave emitted from the set radio wave star at the set observation time (step S202). For the reception of radio waves from such radio wave stars, general interstellar radio wave reception technology can be used.

Next, the sending unit 103 sends the received radio wave signal to the other random number string sharing device 101 (step S203), and the receiving unit 104 receives the radio wave signal sent from the other random number string sharing device 101. (Step S204). As a result, both random number sequence sharing devices 101 share the radio signal received by each. Various communication technologies such as using a normal computer communication network can be applied to the sending and receiving.

Then, the analysis unit 105 analyzes the received radio wave signal and the received radio wave signal into a plurality of independent components (step S205).

Independent component analysis is one of the methods for analyzing multidimensional signals, and seeks a transformation for separating signals by independence based on higher-order statistics and temporal correlation of a target signal group. Known techniques can be used for detailed calculations to obtain this matrix.

Independent component analysis only assumes that the signal source of the target signal group is independent, and is applied in the fields of BSS (Blind Source Separation) and BSD (Blind Source Deconvolution). Achievements in this field include techniques for classifying voices for each speaker from inputs to multiple microphones and for classifying brain waves from electrical signals detected in each part of the head.

As a result, the component received on one side of the radio wave from the set radio wave star, the component received on the other side of the radio wave from the set radio wave star, and the component in each of the radio waves from the other radio wave stars, The components of each of the various noise radio waves can be separated.

In the basic technique of the independent component analysis technique, M signals (corresponding to two received signals in this embodiment) to M independent components (in this embodiment, set radio stars). (Corresponding to the component received on one side and the component received on the other side) is often obtained from, but if there is a correlation between the separated signal components, N (N&gt; M) from M signals. In this embodiment, such a technique is used because it is possible to estimate the number of independent components.

Next, the time difference acquisition unit 109 determines the arrival time difference from the location where each of the plurality of random number sequence sharing devices 101 is arranged, the location of the predetermined radio wave star, and the predetermined observation time. Get (step S206).

If the technology used in VLBI etc. is used, the difference between the information on the revolution and rotation of the earth and the observation time, the location of the radio star in the celestial sphere, and the location of the radio star and the location of both random number sequence sharing devices 101, The arrival time difference can be calculated by dividing this distance difference by the speed of light.

On the other hand, the selection unit 106 selects two independent components that are offset by the acquired arrival time difference from the plurality of independent components analyzed for independent components (step S207).

As described above, since the receiving unit 102 tries to receive the radio wave from the set radio wave star, it is expected that the radio wave from the set radio wave star can be received with a certain amount of electric power. Therefore, when analyzed into multiple independent components, in most cases, the component received on one side of the radio waves from the set radio wave star and the component received on the other side of the radio waves from the set radio wave star. , It is expected that two independent components will be obtained.

If it cannot be selected here, it means that the sharing of the random number sequence has failed, and the process is terminated by reporting that fact (not shown).

Further, the sampling unit 107 bit-samples the average of the two selected independent components, the one that precedes in time and the one that delays by the arrival time difference, and the one that follows, with a predetermined accuracy. (Step S208). As the "average" here, a weighted average may be used. Also, when selecting only one or the other as the weight, it is not "average" but "preceding of the two selected independent components" or "later of the two selected independent components". You may adopt "what you do".

If the one that precedes in time is delayed by the difference in arrival time, there is no time lag with the one that follows, so if the average with the one that follows is taken, a time series can be obtained. Therefore, if bit sampling is performed with the precision to be used, a random number sequence can be obtained.

Finally, the output unit 108 outputs the sampled sequence of bit samples as a random number sequence shared with the other random number sequence sharing device (step S209), and ends this process.

The present invention is based on the hypothesis in radio astronomy that "radio waves emitted from radio stars that are billions of light-years away are random." Then, by removing various noise radio components using independent component analysis, the signal from the random signal source (radio star) is shared by the two random number string sharing devices 101, and as a common key in the encryption / decryption system. You can get a sequence of random numbers that you can use.

(Cryptographic Decryption System) FIG. 3 is a schematic diagram showing an outline configuration of a cryptographic decryption system using the above-mentioned random number sequence sharing device 101. FIG. 4 is a flowchart showing a control flow of the encryption process executed by the encryption device in the encryption / decryption system and the decryption process executed by the decryption device. Hereinafter, description will be made with reference to this figure.

The encryption / decryption system 301 of the present embodiment includes an encryption device 321 and a decryption device 341 that utilize the random number sequence sharing device 101.

In this embodiment, the Burnham cipher is used. The Burnham cipher obtains a bit string from each bit contained in the shared random number string by selectively extracting one of the bits according to a predetermined (public) sampling rule, and obtains a bit string, which is used as the key of the cipher. Use as. As is well known, Burnham cryptography is a completely secure system, as described below, unless the shared random number sequence itself is known to an eavesdropper.

Here, the encryption device 321 includes a key generation unit 361, a reception unit 322, an encryption unit 323, and a transmission unit 324.

On the other hand, the decoding device 341 includes a key generation unit 361, a reception unit 342, a decoding unit 343, and an output unit 344.

First, in the encryption device 321, the key generation unit 361 selects a sequence of random numbers output from the random number sequence sharing device 101 of the encryption device 321 according to the sampling rule, and uses this as the Burnham encryption key ( Step S401).

Similarly, in the decryption device 341, the key generation unit 361 selects a sequence of random numbers output from the random number sequence sharing device 101 of the decryption device 341 according to the sampling rule, and uses this as a burnham encryption key (step). S402).

Since the random number sequence sharing device 101 possessed by the encryption device 321 and the random number sequence sharing device 101 possessed by the decryption device 341 form a random number sequence sharing system, the Burnham encryption keys obtained by both are the same. .. That is, the common key is safely shared.

In the encryption device 321, the reception unit 322 receives the information to be transmitted to the decryption device (step S403), and the encryption unit 323 burnam-encrypts the received information with the generated burnham encryption key (step S403). Step S404), the transmitter 324 transmits the encrypted information to the decryption device 341 (step S405).

On the other hand, in the decryption device 341, the reception unit 342 receives the encrypted information transmitted from the encryption device 321 (step S406), and the decryption unit 343 is accepted by the generated Burnham encryption key. The information is burnam-decrypted (step S407), and the output unit 344 outputs the decrypted information as information transmitted from the encryption device (step S408).

In the above embodiment, both the encryption device 321 and the decryption device 341 are further provided with a rule reception unit (not shown), and the rule reception unit is prepared in advance before communication is performed. It may be configured to accept the input of the sampling rule to be shared from the plurality of sampling rules.

In Burnham cryptography, a binary random number sequence B of length J bits^JIt is assumed that the same public file consisting of is available on the encryption side and the decryption side. In addition, B^JIs generally different from the one output from the random number string sharing device 101, and is prepared in advance. And J is big enough, B^JIs a true random number sequence.

Then, the random number sequence output from the random number sequence sharing device 101 (called "key sequence for Burnham encryption") K = K.₁K₂... each bit K_p, Public file B^JCryptography B^JSampling rule from F_αMake by sampling according to (p). Here, α is a parameter that determines the sampling rule, and when the size of α is L bit, it is 2^LThere will be one sampling rule.

According to Burnham cryptography, the system is completely secure unless the contents of K are known to eavesdroppers. An eavesdropper who does not know α, in order to obtain K, all sampling rules F_αYou need to try (p).

For example, if L = 100, the sampling rule type is 2.¹⁰⁰≒10³³There is a street. Eavesdropper is F_αCalculate (p) once and K from the public file_p10 by the time 1 bit is taken out^-10If it takes seconds, that F_αAt least 10 to determine if (p) is the rule actually used^-10It takes seconds.

In this case, if F over 100 years_αEven if you check (p), you can check F_αThe number of (p) is about 3 × 10¹⁹It's just an individual. Therefore, the probability that an eavesdropper will get K is 10¹⁹/10³³ = 10^-14Is very small.

As mentioned above, K is obtained as a shared random number using radio stars, (a) radio stars to be used, (b) observation time, (c) radio signals received by one, and (d) received by the other. Radio signal (e) If all the arrival time differences between the two are not available, the eavesdropper cannot obtain them. In particular, since the radio signal of a radio star has an extremely wide frequency bandwidth of several tens to several hundreds of GHz, it is extremely difficult for an eavesdropper to store information for continuously monitoring random numbers.

Therefore, the above-mentioned encryption / decryption system can be said to be extremely secure.

As described above, a random number sequence sharing system, a random number sequence sharing device, a cryptographic decryption system, a cryptographic device, a decryption device, a random number string sharing method, a cryptographic method, a decryption method, and these are used. It is possible to provide a program realized on a computer, and it can be applied to the field of encrypted communication.

<figref num="1">It is a schematic diagram which shows the outline structure of the random number string sharing apparatus which concerns on embodiment of this invention.</figref><figref num="2">It is a flowchart which shows the flow of control of the random number string sharing process which concerns on embodiment of this invention.</figref><figref num="3">It is a schematic diagram which shows the outline structure of the encryption / decryption system which concerns on embodiment of this invention.</figref><figref num="4">It is a flowchart which shows the control flow of the encryption process which is executed by the encryption apparatus in the encryption and decryption system which concerns on embodiment of this invention, and the decryption process which is executed by the decryption apparatus.</figref>

Code description

101 Random number sequence sharing device 102 Receiver 103 Send 104 Reception 105 Analysis 106 Selection 107 Sampling 108 Output 301 Encryption / decryption system 321 Encryption 322 Reception 323 Encryption 324 Transmitter 341 Decryptor 342 Receiver 343 Decryption unit 344 Output unit 361 Key generation unit