WO1997031449A1 - Methode de communication utilisant une cle cryptographique commune - Google Patents
Methode de communication utilisant une cle cryptographique commune Download PDFInfo
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- WO1997031449A1 WO1997031449A1 PCT/JP1997/000433 JP9700433W WO9731449A1 WO 1997031449 A1 WO1997031449 A1 WO 1997031449A1 JP 9700433 W JP9700433 W JP 9700433W WO 9731449 A1 WO9731449 A1 WO 9731449A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
- H04L9/0819—Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s)
- H04L9/083—Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
- H04L9/0838—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these
- H04L9/0847—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these involving identity based encryption [IBE] schemes
Definitions
- the present invention relates to a method for sharing a code key for performing cryptographic communication between entities on a network.
- entity-side communication data plaintext
- an encryption key sharing method in which an encryption is performed by a key and transmitted to a receiving entity, and the receiving entity decrypts the original communication data using the same encryption key as the transmitting side.
- the entity means an entity that performs communication, such as a device such as a terminal connected to a network, a user of the device, a software of the device, or a set thereof.
- a center algorithm established in advance in a center established on a network applies a center algorithm that is unique to each entity and that has a public identifier (name, address, etc.) in secret only by Sendai. Is fixed for each entity It is distributed to each entity as a private key. Then, when communicating between the entities, each of the entities generates a common encryption key between the entities by applying the identifier of the entity at the other end of the communication to the private key held by itself. The communication data is encrypted and decrypted using the common encryption key.
- each entity merely applies the identifier of the communication partner to its own private key, and can be shared with any other entity without involvement of the center. Since the encryption key can be obtained, the encryption communication system in the network can be simplified.
- the present invention provides an encryption key sharing method that can increase the security against various attacks while generating a common encryption key for communication, simplifying the encryption communication system on the network.
- the purpose is to provide. Disclosure of the invention
- a first aspect of the encryption key sharing method of the present invention is to perform encryption / decryption of communication data between entities performing communication in a network including a plurality of entities and a center.
- a private key unique to each entity is generated by conversion by a center algorithm including an algorithm, and the private key and the integral conversion algorithm are distributed to each entity, and the entities communicate with each other.
- the private key of each entity is generated by converting the identifier of each entity by the center algorithm including the integration conversion algorithm in the session.
- the identifier of each entity Even if the dispersiveness of itself is poor, the integral transform algorithm acts on the identifier, so that the resulting dispersiveness can be enhanced. Therefore, the dispersibility of the private key is enhanced, and the similarity is poor for each entity, and the private key is generated at the sensor, and is distributed to each entity together with the integral conversion algorithm. . Then, when communicating between the entities, each entity applies the integral conversion algorithm and the private key held by itself to the identifier of the entity at the other end of the communication.
- the private key of each entity includes a component based on the integral transformation algorithm, it is necessary to apply not only the private key but also the integral transformation algorithm to the identifier of the entity on the communication partner side. Then, a common encryption key is generated between the communicating entities by the algorithm part (this part has the above-mentioned symmetry) except for the integral conversion algorithm of the center algorithm.
- each identifier for generating a common encryption key at the time of communication is converted by converting the identifier of each entity by the sensor algorithm including the integral conversion algorithm. Since a private key unique to the entity is generated, the dispersibility of the private key is enhanced, and as a result, the security against differential attacks and the like is enhanced. At the time of communication, only the identifier of the communication partner is allowed to act on the integral conversion algorithm and the private key held by itself, and a common connection with the entity of the communication partner is obtained without involvement of the center as in the past. An encryption key can be generated.
- the first aspect of the present invention it is possible to improve the security against attacks such as differential attacks while generating a common encryption key for communication and simplifying the cryptographic communication system on the network. As a result, a simple and reliable cryptographic communication system can be provided.
- the identifier is fixedly used for each entity, such as a mail address on the network, a domain name, or a combination thereof, in addition to the name and address of each entity, and at least to the communication partner. Anything that is open to the public is acceptable.
- the integral transform algorithm includes a Fourier transform (including a fast Fourier transform), a Laplace transform, a Miller transform, and a Hilbert transform.
- the forces that can use any of these integral transformations, and these integral transformations are defined on an analytical infinite interval.
- the identifier converted by the integral conversion algorithm in the first embodiment of the present invention is represented by a finite interval (for example, a coset on a finite ring).
- the integral conversion algorithm uses an integral conversion algorithm with a weight function.
- a weighting function when performing integral conversion on an identifier, the above-described abnormal dispersion can be prevented.
- the weight function can be set arbitrarily as long as it can prevent anomalous dispersion, the private key obtained by converting an identifier by a center algorithm including an integral conversion algorithm to which the weight function is added is used. , An unknown component based on the weight function is added. As a result, the security of the cryptographic communication system to which the first aspect of the present invention is applied can be further improved.
- the weight function is basically set so that the value approaches “0” at the end of the data section of the identifier.
- the weight function is determined to be an unpredictable pattern by the random number data generated in the center, and more preferably, one-time random number data is used as the random number data.
- the weight function is determined by the random number data by determining the degree of change of the value of the weight function in the section of the identifier data (a form approaching “0” at the end of the section) by the random number data. Is done.
- One-time random data is random data that has no or very poor reproducibility. The random number data is not correlated. Such random number data can be generated, for example, based on the timing when a human inputs a certain phrase or sentence to a computer.
- the weight function By determining the weight function in an unpredictable pattern based on the tongue L number data in this way, it becomes difficult for an attacker to predict the weight function, and the cryptographic communication to which the first aspect of the present invention is applied is difficult.
- the security of the system can be increased. Especially once When the weight function is determined based on the random number data of the sex, the reproducibility of the random number data is eliminated, so that the security of the system is further enhanced.
- the integral conversion algorithm As described above, various types of the integral conversion algorithm can be applied.
- the Fourier transform is an integral transform that can be performed quickly and easily using a computer, and generally, the data of the transform result is likely to be dispersed. Therefore, by using such a Fourier transform algorithm as an integral transform algorithm, the private key can be generated quickly and easily from an identifier, and at the same time, the dispersibility of the private key is effectively increased. The security of the cryptographic communication system can be significantly improved.
- the center further converts the identifier by the center algorithm into one-piece random number data unique to each entity and unknown to each entity.
- To generate the above-mentioned private key by performing randomization conversion according to the above-mentioned method, and an identifier conversion algorithm comprising the algorithm for canceling the randomization conversion component included in the private key and the indirect conversion algorithm together with the private key.
- the entities communicate with each other, the entities are shared by applying the identifier conversion algorithm and the private key held by themselves to the identifiers of the communicating parties. Own the encryption key.
- the randomizing transformation may be performed by changing the value of each bit of a data string representing the identifier converted by the center algorithm by the individual random number data, or Alternatively, they are performed by combining and processing them.
- the private key includes a component obtained by the randomization transformation.
- the randomize transform converts the transform into unique random data of one time (unreproducible or extremely poor reproducibility) unique to each entity and unknown to each entity.
- each individual key of each entity will contain a separate, accidental component.
- security against various attacks on cryptographic communication systems Can be further strengthened.
- the private key that acts on the identifier of the entity on the other end contains a component obtained by the randomization transformation for each entity. For this reason, an identifier conversion algorithm including an algorithm for canceling this and the integral conversion algorithm is distributed to each entity together with the private key, and upon communication, the identifier conversion algorithm is assigned to the identifier of the other entity.
- the randomization conversion is performed, for example, by rearranging and converting a data string representing a result of conversion of the identifier of each of the entities by the sensor algorithm using the one-time individual random number data. This can be done by:
- a data string representing a result obtained by converting the identifier of each entity by the center algorithm includes a plurality of unnecessary bits, and the randomizing conversion is performed by converting the value of the unnecessary bits to the one-time individual random number data. , And by rearranging the entire data sequence including the unnecessary bits. In this way, the value of the unnecessary bit of the data string representing the result of the conversion of the identifier of each entity by the center algorithm is randomized with the one-time individual random number data, and the entire data string including the unnecessary bit is further randomized.
- the attacker decryptor of the cryptographic communication system
- the security of the cryptographic communication system is increased.
- the one-time individual random number data for performing the randomizing transformation is generated based on the predetermined processing of each entity described above. More specifically, the predetermined processing is performed by each entity. This is an input operation by a human, and the one-time individual tongue number data is generated based on the temporal timing of the input operation.
- the tongue number data is not reproducible or reproduced. Very poor One-time individual random number data can be generated accurately.
- a common cipher for performing encryption / decryption of communication data between entities performing communication in a network including a plurality of entities and a center.
- a randomization transformation is performed by an individual random number data unique to each entity and unknown to each entity to generate a private key unique to each entity, and the private key and the private key are generated.
- an identifier conversion algorithm including an algorithm for canceling out the components of the randomization transformation included in the
- the private key of each entity is obtained by using the center algorithm (which includes the above-mentioned symmetric part) in the center to identify each entity. Generated by subjecting the transformed data to randomizing transformation based on unique random data (random data with no or very low reproducibility) unique to each entity and unknown to each entity. Therefore, each individual key of each entity contains a different accidental component. As a result, the security against various attacks of the cryptographic communication system to which the second aspect of the present invention is applied is enhanced. In this case, similarly to the case described in the first aspect, since the private key of each entity includes a component by the randomization transformation for each entity, an algorithm for canceling the component is used.
- the identifier conversion algorithm including the scheme is distributed to each entity together with the private key. Then, at the time of communication, by applying the identifier conversion algorithm and the private key to the identifier of the entity on the other end, it is possible to generate a common encryption key between the entities performing communication without involvement of the center. You can.
- the randomizing conversion is performed by converting a data string representing a result obtained by converting the identifier of each entity by the center algorithm to the first algorithm. This can be done by converting the arrangement using the individual random number data of the roundness. More preferably, the data string representing a result of conversion of the identifier of each entity by the center algorithm includes a plurality of unnecessary bits, and the randomizing conversion includes: The randomization is performed by random number data, and the entire data sequence including the unnecessary bits is rearranged and converted. Thereby, the security of the cryptographic communication system to which the second aspect of the present invention is applied can be improved.
- the one-time individual random number data is generated based on a predetermined process of each entity, and Specifically, the predetermined process is an input operation by a human of each of the entities, and the one-time individual random number data is generated based on a temporal timing of the input operation. Thereby, the one-time individual random number data can be accurately generated.
- FIG. 1 is a diagram showing the overall configuration of a cryptographic communication system to which an embodiment of the cryptographic key sharing method of the present invention is applied
- FIG. 2 is a diagram for conceptually explaining the basic structure of the system in FIG. Is a flow chart for explaining the outline of the processing procedure in the system of FIG. 1
- FIG. 4 is a flowchart showing details of the processing at the time 1 in FIG. 3
- FIG. 5 is the processing in step 2 of FIG.
- Fig. 6 is a flowchart showing details of the processing in steps 3 and 4 in Fig. 3
- Fig. 7 is a flowchart showing details of the processing in steps 3 and 5 in Fig. 3.
- FIG. 8 is a block diagram showing a configuration of a computer machine for performing the processes of FIGS. 6 and 7. BEST MODE FOR CARRYING OUT THE INVENTION
- a center 1 which is a basic construction entity of a cryptographic communication system, and a plurality of entities 2 which subscribe to the cryptographic communication system and mutually perform cryptographic communication are connected to the Internet and a personal computer. They can communicate with each other via a network 3 such as a communication network.
- the center 1 and each entity 2 include a computer machine such as a personal computer for performing actual communication and data processing, and a user of the computer machine.
- each entity 2 subscribed to the center 1 (in FIG. 2, each entity 2 is indicated by a reference numeral j,...) Each has a unique identifier yi, yj, ... (details will be described later). In this case, if i ⁇ j, then y i ⁇ y j. Each entity 2 (i, j, ...) has a unique identifier for each entity 2 generated by the center 11 based on the respective identifiers yi, yj, ... (hereinafter collectively referred to as identifiers yn as necessary).
- the private keys Xi, Xj,... (details will be described later.
- private keys ⁇ when performing cryptographic communication between arbitrary entities i and j, a common encryption key K ij for encrypting (transmitting side) and decrypting (receiving side) the communication data is set for each entity.
- a private key Xi, Xj of each entity i, j is generated separately for each i, j, and cryptographic communication is performed between the entities i, j using the common encryption key ⁇ .
- the identifier yn of each entity 2 is unique to each entity 2 such as the name, address, email address, domain name, or a combination thereof of each entity 2.
- each identifier yn for example, Is treated as a vectorite, formed by coding with cosets of.
- the center 1 In the preparatory processing by the center 1, when the center 1 is established or when the system is updated, first, the center 1 generates a basic center algorithm for generating the private key Xn of each entity 2 (procedure 1).
- the center algorithm is composed of a center matrix, a weight function, and an integral transformation algorithm.
- the integral transformation algorithm is an algorithm for performing integral transformation on the data of the identifier yn of each entity 2.
- a Fourier transform (more specifically, a fast Fourier transform) is used as the integral transformation algorithm. I do.
- a Fourier transform more specifically, a fast Fourier transform
- a plurality of types are known, and one of them is selected at the center 1 to generate a Fourier transform algorithm used in the present embodiment. Is actually represented as a matrix acting on the data of the identifier yn.
- the weighting function is used to prevent anomalous dispersion (ashiering) when the Fourier transform is performed on the identifier yn, which is the data of the finite interval, and the value is “0” at the end point of the data interval of the identifier yn.
- the center matrix is a symmetric matrix, more specifically a nonsingular symmetric matrix.
- the weight function and the center matrix are generated using one-time random number data. That is, referring to FIG. 4, when generating the weight function and the center matrix, the center 11 first generates random number data based on an artificial operation of the computer in the center 1 (step 11). 1). Specifically, for example, Operetu enters appropriate words and phrases into the computer machine of Center 1, and the input timing (eg, the input time of each word and the time interval of input of each word) at this time. Is sequentially measured by a computer machine. And the measured input The random number data is generated in time series based on the data. The random number data generated in this manner is generated based on the timing of an artificial input operation having ambiguity, so that it is practically unreproducible and accidental. A random number is generated.
- the center 1 determines the weighting function and the sentiment matrix based on the generated one-time random number data (step 1). 1 2).
- the weight function is determined by determining the degree of change of the value of the weight function in the section of the data with the identifier yn (a form approaching “0” at the end of the section) based on the one-time random number data.
- the weight function is determined to be a pattern that cannot be predicted.
- the weight function is actually expressed as a diagonal matrix.
- the determination of the center matrix is performed by determining the values of the components of the matrix based on the one-time random number data while securing the symmetry and non-singularity.
- the center algorithm consisting of the weight function and the integral transformation algorithm is kept secret in the center 1.
- the center matrix and the weight function are used by third parties other than the specific person of the center 1 (including each entity 2 etc.). ) Stored strictly so that it cannot be referenced. These algorithms are common to each entity 2.
- the center 1 identifies the center algorithm and the identifier of each entity 2 generated and stored as described above.
- a private key X n unique to each entity 2 and an identifier conversion algorithm for generating a common encryption key ⁇ ⁇ as described later are generated and distributed to each entity 2 as described below. (Step 2).
- the center 1 applies the aforementioned Fourier transform algorithm and the matrix of the weight function to the data (vector data) of the identifier yn of the entity 2. Then, a weighted high-speed free transform is performed on the identifier yn (step 2-1). Further, the vector data obtained in step 2-1 is multiplied by the center one matrix (step 2-2). In this case, by adding redundancy to the data of the identifier yn, the vector obtained in step 2-2 can be obtained. In the data, there appear a plurality of useful bits obtained by applying the weight function, the integral conversion algorithm and the center matrix to a bit string meaningful as the data of the identifier yn, and a plurality of other unnecessary bits.
- the center 1 communicates with the entity 2 (for example, communication at the time of recruitment of the entity 2), and has a unique random number unique to the entity 2 and which cannot be recognized by the entity 2.
- Generate the data (step 2-3). Specifically, in the same way as when generating one-time random number data when determining a weight function or the like as described above, a word or sentence of a user is input on the computer machine of the entity 2 The timing of artificial input operation of the entity 2 is measured by the computer machine of the center 1 by sequentially receiving the data at the center 1. Then, the individual random number data is generated based on the measured timing of the input operation.
- the individual random number data becomes accidental with no reproducibility, like the random number data at the time of generation of the weight function, etc.
- one-time individual random number data can be obtained. Since the entity 2 does not know what kind of input operation timing and what kind of random number data is generated, and cannot control the artificial input operation timing accurately, the entity 2 Entity 2 cannot know the random number data.
- Sen-ichi 1 uses the one-time individual random number data obtained in Step 2-3 to convert each bit value of the unnecessary bits in the vector data obtained in Step 2-2 above. Randomization (steps 2-4). Further, the vector data obtained by combining the randomized unnecessary bits and the useful bits is randomly rearranged and converted using the one-time individual random number data (the arrangement of the vector data components is changed. 2-5) The randomizing transformation is performed on the vector data obtained by this in step 2-2 (the identifier yn is converted by the Senyuichi algorithm). Then, the vector obtained by the randomizing transformation is generated as the private key Xn of the entity 2.
- the randomizing transformation is actually represented by a matrix (not necessarily a symmetric matrix), and more specifically, a matrix such that the transposed matrix and the inverse matrix of the matrix are equal.
- the center 1 generates the identifier conversion algorithm from the one-time individual random number data, the Fourier transform algorithm, and the weight function (step 2-6).
- the identifier conversion algorithm includes an algorithm for canceling the randomized transformation component reflected in the private key Xn (this is represented by an inverse matrix of a matrix representing the randomized transformation), the Fourier transformation algorithm, It is the result of combining the two functions with each other (multiplying the matrices representing each of them).
- the personal key Xn and the identifier conversion algorithm corresponding to each entity 2 generated by the center 11 are distributed to each entity 2 in advance by communication or the like (see step 2 in FIG. 3).
- the contents described above are details of the advance preparation processing in the center 1.
- the center 1 After generating the private key Xn and the identifier conversion algorithm of each entity 2 as described above, the center 1 obtains the one-time individual random number data corresponding to the entity 2 and the matrix representing the randomization conversion. Erase without storage. In addition, each entity 2 that has received its own private key Xn and identifier conversion algorithm keeps them secretly in an appropriate storage device of its own computer machine.
- communication between arbitrary entities 2 is performed as follows.
- the communication is performed with the entity i as the transmitting side and the entity j as the receiving side.
- the transmitting entity i first obtains a common encryption key K ij with the entity j from the private key X i and the identifier conversion algorithm held by the transmitting entity i and the identifier y j of the receiving entity j. Generate (Step 3).
- the identifier conversion algorithm of the entity i is applied to the identifier yj of the entity j on the receiving side on the computer machine of the entity i of the transmitting side (the vector In the evening, multiply by the matrix of the identifier conversion algorithm Step 3-1).
- a common encryption key Ki j with the entity j is generated by calculating the inner product of the vector data obtained in this step 3-1 and the private key X i of the transmitting entity i (vector e).
- the receiving entity j applies its identifier conversion algorithm to the identifier yi of the transmitting entity i on its combi- ter machine as shown in Fig. 7 (step 3-1).
- a common encryption key Kji with entity i is generated.
- the common encryption key KU uniquely generated by the transmitting entity i and the common encryption key Kji uniquely generated by the receiving entity j are the same.
- the transmitting side and receiving side entities i and j, and the private keys Xi and Xj held respectively, are respectively assigned to the identifiers yi and yj of the entities i and j by the Fourier transform algorithm with the weight function described above.
- a vector matrix obtained by applying a center matrix and a randomizing transformation, and when each entity i, j generates a common encryption key ⁇ , Kji, the identifier yj of the entity j, i on the other side , yi, the identifier conversion algorithm is a combination of a Fourier transform algorithm with a weighting function and an algorithm that cancels out the components of the randomization transform for each entity i, j reflected in each private key Xi, Xj. Things.
- each common encryption key Kij, Kji obtained as a result of the inner product operation is calculated for each entity i, j , j, which are obtained by applying a Fourier transform algorithm with a weighting function to the identifiers yi, yj, and by further applying a center matrix (vector data processing), and the identifiers yj,
- a Fourier transform algorithm with a weighting function to the identifiers yi, yj
- vector data processing the identifiers yj
- the vector data obtained by applying the Fourier transform algorithm with the weighting function to the identifiers yi and yj are set as yi 'and yj' (where yi 'and yj' are vertical vectors), and the sensor matrix is C
- the transmitting entity i that has generated K ij generates an encrypted communication message from the common encryption key Ki j and the plaintext (text, program, etc.) to be transmitted to the receiving entity j (step 4).
- the # communication message a one-time random number is used in addition to the common encryption key K ij.
- the transmitting entity i uses its own computer machine to generate words, sentences, etc. in the same manner as in the preparatory processing in the center 1 described above.
- One-time random number data (hereinafter referred to as “random number for cryptographic communication”) is generated based on the temporal timing of the input operation (step 4-1), and the random number data for one-time cryptographic communication is generated.
- the encryption is performed by, for example, a three-stage DES (Data Encryption Standard).
- step 41 Is used as a key to encrypt the plaintext (steps 4-3). This encryption is performed, for example, in step 41
- step 4-2 by combining the encrypted random number data obtained in step 4-2 with the ciphertext obtained in step 4-1 (to form one set), an encrypted communication message to be transmitted to the receiving entity j is obtained. Is generated. The encrypted communication message thus generated is transmitted from the computer machine of the entity i to the computer machine of the entity j.
- the random number data for encrypted communication is preferably generated and updated every time encrypted communication is performed, but every time encrypted communication is performed several times, the random number data for encrypted communication is updated (for several times). The same ⁇ ⁇ ! Credit random number data is used in encrypted communication).
- each entity 2 that performs the process for signal communication as described above is configured as shown in, for example, a block diagram of FIG.
- the computer machine of each entity 2 includes a keyboard 4, a main unit 5 composed of a CPU, a RAM, a ROM, etc. (not shown), the private key Xn and an identifier conversion algorithm, plain text such as text and programs, and encryption.
- a database 6 configured by a hard disk or the like that stores and holds communication messages and the like.
- the main unit 5 includes, as its functional components, a common key generation unit 7 for generating a common encryption key, an encryption / decryption processing unit 8 for performing encryption / decryption processing of communication data, and a random number for encryption communication.
- a random number generation unit 9 for generating data, and a common encryption key generated by the common key generation unit 7 during encryption communication and a cryptographic key generated by the random number generation unit 9!
- a data storage memory 10 for storing data such as credit random number data is provided.
- the computer machine of each entity 2 having such a configuration performs the above-described processing for encrypted communication by the following operation.
- Step 3 when generating the common encryption key (Step 3), first, the personal key Xn and the identifier conversion algorithm to be used are transmitted from the keyboard 4 to the main body.
- the specified private key Xn and the identifier conversion algorithm are fetched from the database 6 into the common key generation unit 7 of the main unit 5.
- an identifier yn of the communication partner is input to the main unit 5 through the keyboard 4.
- the common key generation unit 7 of the main unit 5 generates a common encryption key by applying the identifier conversion algorithm and the private key Xn to the input data of the identifier yn as described above (see the procedure 3- 1, 3— 2), the raw The generated common encryption key is stored in the data storage memory 10.
- the keyboard 4 inputs data (input operation data such as words and sentences) for generating the random number data for encrypted communication to the main body unit 5. Then, based on the input data, the random number generation unit 9 of the main unit 5 generates the one-time random number data for cryptographic communication as described above (the above-described procedure 4-1). The random number data is stored in the data storage memory 10. Further, in the transmitting computer machine, the plaintext to be transmitted in the database 6 is determined from the keyboard 4 to the main unit 5, and at this time, the designated plaintext is taken into the decoding unit 8 from the database 6. .
- the encryption / decryption processing unit 8 encrypts the random number data for encrypted communication stored in the data storage memory 10 using the common encryption key also stored in the data storage memory 10 (the procedure described above). Along with 4-2), the plaintext is encrypted using the encrypted random number data as a key (the above-mentioned procedure 4-1-3).
- the random number data and plaintext for encrypted communication encrypted by the encryption / decryption processing unit 8 in this way are stored in the database 6 as an encrypted communication message composed of the encrypted data, and then separately transmitted to the computer machine of the communication partner. Sent to.
- the encrypted communication message is stored in the database 6 and is taken into the encryption / decryption processing unit 8. Then, the decryption processing unit 8 uses the common encryption key stored in the data storage memory 10 to convert the encrypted random number data in the encrypted communication message into the random number data for encrypted communication.
- the encrypted plaintext in the encrypted communication message is decrypted into the original plaintext using the decrypted random number data for encrypted communication as a key (the above-described procedure 5-2).
- the plaintext encrypted by the symbol decoding processing unit 8 in this way is stored in the database 6.
- the center 1 when generating the private key Xn of each entity 2 in the center 1 (preparation processing), the center 1 integrates the identifier yn such as the name of each entity 2.
- the identifier yn such as the name of each entity 2.
- the dispersiveness of the data obtained by Fourier transforming it is improved, and the center matrix etc. is added to the data.
- the dispersibility of the private key Xn can be enhanced. As a result, the so-called difference It is difficult to decipher the center algorithm such as the center matrix of center 1 by an attack or the like.
- a Laplace transform, a Mirai transform, a Hilbert transform, and the like can be used as the integral transform.
- the Fourier transform (more specifically, the fast Fourier transform) is used.
- a weight function is added as a center algorithm, so that anomalous dispersion of data obtained by Fourier transforming the data of the identifier yn on the finite interval can be prevented, and the center
- the decimation of the Senyuichi algorithm can be made more difficult because the number of unknown algorithm elements, such as the center matrix and the Fourier transform algorithm, and the weight function increase.
- the weight function is generated in an unpredictable shape based on one-time random number data, it is possible to more reliably secure the above-mentioned difficulty in decoding.
- each entity 2 includes a component based on a randomizing transformation that has no correlation with each other. For this reason, for example, even if a plurality of entities 2 collude and attempt to decrypt the center algorithm or the like from the private key Xn held by each, it becomes extremely difficult to decrypt the center algorithm.
- the value of the unnecessary bit in the data obtained by applying the Fourier transform, the weight function, and the Sendei-matrix to the identifier yn is randomized by the one-time individual random number data.
- any part of the data of the private key Xn obtained by the randomization conversion includes the data corresponding to the unnecessary bit. It is not known whether or not they have been deciphered, making the above decipherment even more difficult.
- the identifier conversion algorithm including an algorithm for canceling the randomized transformation component reflected in the private key Xn is used. It must be distributed to each entity 2 together with the private key Xn.
- the identifier conversion algorithm is a combination of the algorithm for canceling the components by the randomization transform, the Fourier transform algorithm, and the weighting function, the randomization that constitutes the center algorithm of the center 11 from the identifier conversion algorithm is performed. Algorithm of transformation ⁇ It is extremely difficult to decipher the weight function and Fourier transform algorithm individually.
- the plaintext is once and has no biased characteristic.
- the encryption random number data for encryption is used as a key, and the random number for encryption communication as a key for decrypting the encrypted plaintext is encrypted using a common encryption key K ij.
- K ij the random number for encryption communication as a key for decrypting the encrypted plaintext
- the subscripted is a variable indicating an arbitrary identifier.
- the above linear transformation can be found such that the kernel of the f-input symmetric transformation g follows a multiple linear mapping (f-fold linear mapping), and this linear transformation is basically defined by a linear space on a finite field. And generalized to the coset on the ring.
- the set of entities belonging to the center 1 is E
- the set of identifiers is I
- the set of common encryption keys is K (see Figure i).
- Q be a commutative ring with a unit element
- J be a coset of order m on Q
- K be a coset of order h on Q
- the elements of J and K be m-vertical vectors, h- Let it be a vertical vector. If Q is a field, J and K are linear spaces of dimensions m and h, respectively.
- the order m is equal to the total number of identifiers.
- R is a linear transformation forming a mapping from I to J, and is hereinafter referred to as identity transformation.
- identity transformation is compatible with the system of the above-described embodiment. This basically corresponds to a transform in which a Fourier transform (integral transform) with a weighting function is applied to the data of the identifier, and further extended to a transform including the randomizing transform as described later. .
- a symmetric Q-order multiple linear mapping (a two-input symmetric transformation) from J 2 (a set consisting of two element sets of J as elements) to a set K of common ⁇ keys is g: J 2 ⁇ K is arbitrarily selected and determined. This g is equivalent to the conversion for generating a common encryption key corresponding to those two identifiers from the result of identity conversion of any two identifiers.
- ? 7 is an arbitrary m-longitudinal vector on Q, which is an element of J (hereinafter the same).
- ⁇ (h ⁇ ⁇ ) [Q—operation] means the order of h ⁇ m on the commutative ring Q, and this value is approximately 0 (w 2 ) [bit conversion], that is, w It can be evaluated by order 2 .
- C e (Vi) becomes low.
- the description complexity Cd (Xi) and the evaluation complexity Ce (Xi) of the transformation Xi depend largely on the description complexity Cd (R) and the evaluation complexity Ce (R) of the identity transformation R. Les ,.
- the set B of j can easily know the private key Xi of another entity i.
- the identity transformation R is individualized, since the transformation R is unique to each entity, it can decrypt another private key Xi for a given set B of entities j.
- Finding an entity i with such an identifier yi is not easy.
- the entity j of the set B cannot know which entity i's private key Xi can be decrypted from the information such as the private key Xj possessed by them.
- the latter method of randomizing the identity conversion R individually for each entity is a method realized by the randomization conversion in the above-described embodiment, and according to this method, the total number of identifiers m ( In this system, this is equal to the total number n of entities.)
- the total number of identifiers m In this system, this is equal to the total number n of entities.
- the above inequality specifies the limit on the total number b of entities j required to break the system, and means that the system cannot be broken with the number b of entities for which this inequality does not hold.
- identity conversion R such that even if at most b entities j collude, the private key Xi of another entity i cannot be deciphered. Is derived. Also, it can be seen that individual randomization of the identity transformation R often results in a good linearly independent structure while satisfying the above conditions.
- this system can provide a highly secure system by individually randomizing the identity conversion R.
- the present system increases the description complexity Cd (R) and the evaluation complexity C e (R) of the identity transformation R by individual randomization of the identity transformation R, and consequently the private key Xi
- the system is secured by increasing the description complexity Cd (Xi) and the evaluation complexity Ce (Xi).
- Q GF [2].
- cryptographic communication can be performed between any two entities on the system including up to 11020 entities using the common encryption key of 16 Ob it.
- each personal key can be calculated within 20 ms.
- the system cannot be completely broken unless 8 192 entities collude, and the individual randomization of each entity requires that 256 or more entities collude without collusion. No information is available on the entity's private key.
- a center matrix is set as the center algorithm in addition to the weight function and the Fourier transform algorithm.
- the weight function itself can be used as the center matrix.
- the Fourier transform is used as the integral transform.
- another form of integral transform such as Laplace transform, Miller transform, and Hilbert transform may be used.
- the present invention is useful as a method for easily and securely performing cryptographic communication using a common key method in a network such as the Internet or a personal computer communication network.
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- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Storage Device Security (AREA)
- Computer And Data Communications (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
- Mobile Radio Communication Systems (AREA)
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IL12582997A IL125829A0 (en) | 1996-02-21 | 1997-02-19 | Method of sharing cryptokey |
AU17325/97A AU1732597A (en) | 1996-02-21 | 1997-02-19 | Communication method using common cryptographic key |
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7083596 | 1996-02-21 | ||
JP8/70832 | 1996-02-21 | ||
JP7083296 | 1996-02-21 | ||
JP8/70835 | 1996-02-21 | ||
JP8/210376 | 1996-07-08 | ||
JP21037696 | 1996-07-08 |
Publications (1)
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WO1997031449A1 true WO1997031449A1 (fr) | 1997-08-28 |
Family
ID=27300451
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1997/000432 WO1997031448A1 (fr) | 1996-02-21 | 1997-02-19 | Methode de communication utilisant une cle commune |
PCT/JP1997/000433 WO1997031449A1 (fr) | 1996-02-21 | 1997-02-19 | Methode de communication utilisant une cle cryptographique commune |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP1997/000432 WO1997031448A1 (fr) | 1996-02-21 | 1997-02-19 | Methode de communication utilisant une cle commune |
Country Status (9)
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US (2) | US5987129A (ja) |
EP (2) | EP0792042A3 (ja) |
KR (2) | KR19990087103A (ja) |
CN (2) | CN1211362A (ja) |
AU (2) | AU1732597A (ja) |
CA (2) | CA2247478A1 (ja) |
IL (2) | IL125832A0 (ja) |
TW (2) | TW395103B (ja) |
WO (2) | WO1997031448A1 (ja) |
Families Citing this family (48)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6788788B1 (en) * | 1998-09-16 | 2004-09-07 | Murata Kikai Kabushiki Kaisha | Cryptographic communication method, encryption method, and cryptographic communication system |
KR100484209B1 (ko) * | 1998-09-24 | 2005-09-30 | 삼성전자주식회사 | 디지털컨텐트암호화/해독화장치및그방법 |
US7065210B1 (en) * | 1999-01-25 | 2006-06-20 | Murata Kikai Kabushiki Kaisha | Secret key generation method, encryption method, cryptographic communications method, common key generator, cryptographic communications system, and recording media |
US6907034B1 (en) * | 1999-04-08 | 2005-06-14 | Intel Corporation | Out-of-band signaling for network based computer session synchronization |
US7080255B1 (en) * | 1999-05-19 | 2006-07-18 | Murata Kikai Kabushiki Kaisha | Secret key generation method, encryption method, and cryptographic communications method and system |
US6694025B1 (en) | 1999-06-02 | 2004-02-17 | Koninklijke Philips Electronics N.V. | Method and apparatus for secure distribution of public/private key pairs |
US7203834B1 (en) * | 1999-12-02 | 2007-04-10 | International Business Machines Corporation | Method of updating encryption keys in a data communication system |
JP2001211153A (ja) * | 2000-01-25 | 2001-08-03 | Murata Mach Ltd | 秘密鍵生成方法 |
US20010054147A1 (en) * | 2000-04-04 | 2001-12-20 | Richards Ernest S. | Electronic identifier |
US6718038B1 (en) * | 2000-07-27 | 2004-04-06 | The United States Of America As Represented By The National Security Agency | Cryptographic method using modified fractional fourier transform kernel |
US7031468B2 (en) * | 2000-08-29 | 2006-04-18 | Ntru Cryptosystems, Inc. | Speed enhanced cryptographic method and apparatus |
EP1329051A2 (en) * | 2000-10-18 | 2003-07-23 | Koninklijke Philips Electronics N.V. | Generation of a common encryption key |
EP1233570A1 (en) * | 2001-02-16 | 2002-08-21 | TELEFONAKTIEBOLAGET L M ERICSSON (publ) | Method and system for establishing a wireless communications link |
US20020146127A1 (en) * | 2001-04-05 | 2002-10-10 | Marcus Wong | System and method for providing secure communications between wireless units using a common key |
ATE293334T1 (de) * | 2001-06-12 | 2005-04-15 | Ibm France | Verfahren zum authentifizieren mehrerer mit einem textdokument verbundener dateien |
US9210137B2 (en) * | 2001-08-24 | 2015-12-08 | Thomson Licensing | Local digital network, methods for installing new devices and data broadcast and reception methods in such a network |
WO2004010584A2 (en) * | 2002-07-24 | 2004-01-29 | Congruence Llc. | Code for object identification |
US7190791B2 (en) * | 2002-11-20 | 2007-03-13 | Stephen Laurence Boren | Method of encryption using multi-key process to create a variable-length key |
CA2458123C (en) * | 2003-03-13 | 2012-05-15 | Synodon Inc. | Remote sensing of gas leaks |
WO2004107651A1 (en) * | 2003-05-29 | 2004-12-09 | Telecom Italia S.P.A. | Method, system and computer program for the secured management of network devices |
WO2005032201A1 (en) * | 2003-09-26 | 2005-04-07 | Telefonaktiebolaget Lm Ericsson (Publ) | Enhanced security design for cryptography in mobile communication systems |
KR100561846B1 (ko) * | 2003-10-08 | 2006-03-16 | 삼성전자주식회사 | 가중된 비밀 공유 및 복원 방법 |
CN100421372C (zh) * | 2003-11-18 | 2008-09-24 | 华为技术有限公司 | 一种安全发送传输密钥的方法 |
EP1533971A1 (en) * | 2003-11-18 | 2005-05-25 | STMicroelectronics S.r.l. | Method and system for establishing secure communication |
DE60315853D1 (de) | 2003-12-24 | 2007-10-04 | St Microelectronics Srl | Verfahren zur Entschlüsselung einer Nachricht |
JP4567603B2 (ja) | 2003-12-26 | 2010-10-20 | 三菱電機株式会社 | 被認証装置及び認証装置及び認証方法 |
JP2005210193A (ja) * | 2004-01-20 | 2005-08-04 | Matsushita Electric Works Ltd | 共通秘密鍵生成装置 |
CN100459492C (zh) * | 2004-12-09 | 2009-02-04 | 中国电子科技集团公司第三十研究所 | 一种适用于同步数字系列的加密方法 |
CN100446016C (zh) * | 2005-11-17 | 2008-12-24 | 北京兆维电子(集团)有限责任公司 | 一种实现数据安全保护的系统 |
ES2392854T3 (es) * | 2006-02-10 | 2012-12-14 | Qualcomm Incorporated | Ocultación de identidades temporales de equipos de usuario |
US8332635B2 (en) * | 2007-05-29 | 2012-12-11 | International Business Machines Corporation | Updateable secure kernel extensions |
US8433927B2 (en) * | 2007-05-29 | 2013-04-30 | International Business Machines Corporation | Cryptographically-enabled privileged mode execution |
US7886162B2 (en) * | 2007-05-29 | 2011-02-08 | International Business Machines Corporation | Cryptographic secure program overlays |
US8422674B2 (en) * | 2007-05-29 | 2013-04-16 | International Business Machines Corporation | Application-specific secret generation |
DE102007058163A1 (de) | 2007-09-28 | 2009-04-23 | Continental Automotive Gmbh | Tachograph, Maut-On-Board-Unit, Anzeigeinstrument und System |
US8332636B2 (en) * | 2007-10-02 | 2012-12-11 | International Business Machines Corporation | Secure policy differentiation by secure kernel design |
CN101183938B (zh) * | 2007-10-22 | 2011-11-23 | 华中科技大学 | 一种无线网络安全传输方法、系统及设备 |
KR20100134745A (ko) * | 2008-04-14 | 2010-12-23 | 코닌클리케 필립스 일렉트로닉스 엔.브이. | 분산형 아이덴티피케이션을 위한 방법, 네트워크 내의 스테이션 |
US7522723B1 (en) | 2008-05-29 | 2009-04-21 | Cheman Shaik | Password self encryption method and system and encryption by keys generated from personal secret information |
CN101807997B (zh) * | 2010-04-28 | 2012-08-22 | 中国工商银行股份有限公司 | 一种生成传输密钥的装置及方法 |
CN102279908B (zh) * | 2010-06-08 | 2014-03-12 | 安凯(广州)微电子技术有限公司 | 一种数字内容的保护方法及系统 |
CN103004129B (zh) * | 2010-07-23 | 2015-04-08 | 日本电信电话株式会社 | 加密装置、解密装置、加密方法、解密方法、程序及记录介质 |
US20120079462A1 (en) * | 2010-09-24 | 2012-03-29 | SoftKrypt LLC | Systems and methods of source software code obfuscation |
US10797879B2 (en) * | 2018-07-03 | 2020-10-06 | Lawrence Liu | Methods and systems to facilitate authentication of a user |
CN110351084B (zh) * | 2019-07-17 | 2022-02-08 | 伟志股份公司 | 一种城市基础测绘数据保密处理方法 |
CN111355645A (zh) * | 2020-03-06 | 2020-06-30 | 海信(广东)空调有限公司 | 家用电器、云端服务器及其对应的传输数据的方法 |
CN113162896A (zh) * | 2020-12-23 | 2021-07-23 | 哈尔滨工业大学 | 基于三项加权分数傅里叶变换的物理层安全发射方法 |
CN114363858A (zh) * | 2022-03-21 | 2022-04-15 | 苏州浪潮智能科技有限公司 | 蜂窝车联网协同通信的会话及注册方法、系统及相关组件 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63314585A (ja) * | 1987-06-17 | 1988-12-22 | 日本電気株式会社 | 順序変換表作成装置 |
JPH07175411A (ja) * | 1993-12-20 | 1995-07-14 | Csk Corp | 暗号システム |
JPH07311673A (ja) * | 1990-03-30 | 1995-11-28 | Gao Ges Autom Org Mbh | 乱数発生方法及び乱数発生回路配置 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3798605A (en) * | 1971-06-30 | 1974-03-19 | Ibm | Centralized verification system |
US4238853A (en) * | 1977-12-05 | 1980-12-09 | International Business Machines Corporation | Cryptographic communication security for single domain networks |
WO1988001120A1 (en) * | 1986-07-31 | 1988-02-11 | Kabushiki Kaisya Advance | System for generating a shared cryptographic key and a communication system using the shared cryptographic key |
US5202921A (en) * | 1991-04-01 | 1993-04-13 | International Business Machines Corporation | Method and apparatus for authenticating users of a communication system to each other |
US5297208A (en) * | 1992-08-05 | 1994-03-22 | Roger Schlafly | Secure file transfer system and method |
FR2719925B1 (fr) * | 1994-05-10 | 1996-06-07 | Bull Cp8 | Procédé pour produire une clé commune dans deux dispositifs en vue de mettre en Óoeuvre une procédure cryptographique commune, et appareil associé. |
US5606615A (en) * | 1995-05-16 | 1997-02-25 | Lapointe; Brian K. | Computer security system |
US5778069A (en) * | 1996-04-10 | 1998-07-07 | Microsoft Corporation | Non-biased pseudo random number generator |
-
1997
- 1997-02-19 AU AU17325/97A patent/AU1732597A/en not_active Abandoned
- 1997-02-19 CA CA002247478A patent/CA2247478A1/en not_active Abandoned
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- 1997-02-19 CN CN97192326A patent/CN1211362A/zh active Pending
- 1997-02-19 CA CA002247509A patent/CA2247509A1/en not_active Abandoned
- 1997-02-19 KR KR1019980706491A patent/KR19990087103A/ko not_active Application Discontinuation
- 1997-02-19 IL IL12583297A patent/IL125832A0/xx unknown
- 1997-02-19 CN CN97192374A patent/CN1211363A/zh active Pending
- 1997-02-19 IL IL12582997A patent/IL125829A0/xx unknown
- 1997-02-19 WO PCT/JP1997/000432 patent/WO1997031448A1/ja not_active Application Discontinuation
- 1997-02-19 KR KR1019980706411A patent/KR19990082665A/ko not_active Application Discontinuation
- 1997-02-19 WO PCT/JP1997/000433 patent/WO1997031449A1/ja not_active Application Discontinuation
- 1997-02-20 TW TW086102018A patent/TW395103B/zh not_active IP Right Cessation
- 1997-02-20 TW TW086102019A patent/TW395104B/zh not_active IP Right Cessation
- 1997-02-21 US US08/804,380 patent/US5987129A/en not_active Expired - Fee Related
- 1997-02-21 EP EP97301135A patent/EP0792042A3/en not_active Withdrawn
- 1997-02-21 EP EP97301136A patent/EP0792043A3/en not_active Withdrawn
- 1997-02-21 US US08/801,856 patent/US5987128A/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63314585A (ja) * | 1987-06-17 | 1988-12-22 | 日本電気株式会社 | 順序変換表作成装置 |
JPH07311673A (ja) * | 1990-03-30 | 1995-11-28 | Gao Ges Autom Org Mbh | 乱数発生方法及び乱数発生回路配置 |
JPH07175411A (ja) * | 1993-12-20 | 1995-07-14 | Csk Corp | 暗号システム |
Non-Patent Citations (5)
Title |
---|
ADVANCES IN CRYPTOLOGY: PROCEEDINGS OF CRYPTO94, SPRINGER VERLAG, 1994, JAMES L. MASSEY and SHIRLEI SERCONEK, "A Fourier Transform Approach to the Linear Complexity of Nonlinearly Filtered Sequences", pages 332-340. * |
Authors, HIDEKI IMAI, "Coding Theory", 5th Edition, IEICE, 10 June 1994, pages 158-161. * |
Authors, MASAAKI MITANI, SHIGEO TSUJII, "Digital Signal Processing Series Vol. 3 Digital Filter Design", SHOKODO, 20 April 1987, pages 75-78. * |
IEICE TECHNICAL REPORT ISEC88-5, THE INSTITUTE OF ELECTRONICS, INFORMATION AND COMMUNICATION ENGINEERS OF JAPAN, Vol. 88, No. 33, 20 May 1988, MATSUMOTO T. and IMAI H., "Performance of Linear Schemes for the Key Predistribution System", pages 29-32. * |
THE TRANSACTION OF IEICE, Vol. J71-A, No. 11, 25 November 1988, TSUTOMU MATSUMOTO, HIDEKI IMAI, "A Method for Sharing Cryptography Key Without Communication: Key Predistribution System", pages 2046-2053. * |
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KR19990082665A (ko) | 1999-11-25 |
IL125829A0 (en) | 1999-04-11 |
KR19990087103A (ko) | 1999-12-15 |
TW395103B (en) | 2000-06-21 |
IL125832A0 (en) | 1999-04-11 |
EP0792043A3 (en) | 2000-12-20 |
AU1732497A (en) | 1997-09-10 |
CA2247509A1 (en) | 1997-08-28 |
US5987129A (en) | 1999-11-16 |
EP0792042A3 (en) | 2000-12-27 |
EP0792043A2 (en) | 1997-08-27 |
WO1997031448A1 (fr) | 1997-08-28 |
CN1211362A (zh) | 1999-03-17 |
CN1211363A (zh) | 1999-03-17 |
CA2247478A1 (en) | 1997-08-28 |
US5987128A (en) | 1999-11-16 |
EP0792042A2 (en) | 1997-08-27 |
TW395104B (en) | 2000-06-21 |
AU1732597A (en) | 1997-09-10 |
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