Privacy-protected transfer of electronic information
OwnerStefanus A. Brandsinventor
Life of this patent
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Abstract
Cryptographic apparatus and means are disclosed for each of three types of participants in an electronic system for privacy-protected transfer of certified information. This invention reveals protocols that improve efficiency and security in such systems, and allows a variety of useful extensions in functionality without difficulty. This is achieved by a restrictive blind signature protocol in combination with a testing protocol. The restrictive blind signature protocol allows the certifying party to encode data into certified information that it provides to a receiving party, such that it cannot be altered or modified by the receiving party. The testing protocol enables parties to prove a variety of characteristics about the encoded data in their certified information.
Claims53
A method for a first party to have information certified by a second party by generating a signal representative of a digital certificate corresponding to a vector of numbers, wherein the signals representative of the vector of numbers and the digital certificate are hidden from the second party, yet the second party is ensured that a representation, known by the first party, of at least one number in the vector of numbers, contains the information to be certified, the method comprising the steps of:
- generating by the second party, a signal representative of a secret key and a corresponding public key, and providing a specification of the correspondence between the signals representative of the digital certificates and vectors of numbers with respect to the public key;
- randomly transforming by the first party, signals representative of the information to be certified, into a vector of numbers, such that the first party knows a representation of at least one number in the vector of numbers, and the representation contains the information to be certified;
- computing by the first party, challenge information, and transmitting signals representative of the challenge information to the second party;
- computing by the second party, response information based on at least the challenge information and the secret key, and transmitting signals representative of the response information to the first party;
- and
- computing by the first party, based on at least the received response information, a digital certificate corresponding to the vector of numbers.
A method for a first party which knows a first representation, where a first representation is a representation of at least one number in a vector of numbers with respect to a first function, to transmit to a third party a signal constituting a second representation, where a second representation is a representation of a second function of the at least one number in the vector of numbers with respect to a third function, the first party having previously generated a signal representative of a digital certificate corresponding to the vector of numbers with respect to a public key of a second party, the method comprising the steps of:
- providing by the first party to the third party, signals representative of the vector of numbers and the digital certificate;
- computing by the first party, in response to challenge information, response information based on at least the challenge information and the second representation, and transmitting signals representative of the response information to the third party;
- and
- verifying by the third party, that the digital certificate corresponds to the vector of numbers with respect to the public key and that the response information corresponds to the challenge information, the second function of the at least one number in the vector of numbers, and the third function.
A method for a first party to have information certified by a second party by generating a signal representative of a digital certificate corresponding to a vector of numbers, wherein the signals representative of the vector of numbers and the digital certificate are hidden from the second party, yet the second party is ensured that the information to be certified is contained in a representation known by the first party of at least one number in the vector of numbers with respect to a first function, and then to transmit to a third party a signal constituting a representation of a second function of the at least one number in the vector of numbers with respect to a third function, the method comprising the steps of:
- generating by the second party, a signal representative of a first secret key and a corresponding first public key, and providing a specification of the correspondence between the signals representative of the digital certificates and vectors of numbers with respect to the first public key;
- randomly transforming by the first party, signals representative of the information to be certified, into a vector of numbers, such that the first party knows a first representation, where a first representation is a representation of at least one number in the vector of numbers with respect to the first function, and the first representation contains the information to be certified;
- computing by the first party, first challenge information, and transmitting signals representative of the first challenge information to the second party;
- computing by the second party, first response information based on at least the first challenge information and the first secret key, and transmitting signals representative of the first response information to the first party;
- computing by the first party, based on at least the received first response information, a digital certificate corresponding to the vector of numbers;
- transmitting by the first party to the third party, signals representative of the vector of numbers and the digital certificate;
- computing by the first party, in response to second challenge information, second response information based on at least the second challenge information and a second representation, where a second representation is a representation of the second representation is a representation of the second function of the at least one number in the vector of numbers with respect to the third function, and transmitting a signal representative of the second response information to the third party;
- and
- verifying by the third party, that the digital certificate corresponds to the vector of numbers with respect to the first public key and that the second response information corresponds to the second challenge information, the second function of the at least one number in the vector of numbers, and the third function.
An apparatus for a first party to have information certified by a second party by generating a signal representative of a digital certificate corresponding to a vector of numbers, wherein the signals representative of the vector of numbers and the digital certificate are hidden from the second party, yet the second party is ensured that a representation, known by the first party, of at least one number in the vector of numbers, contains the information to be certified, the apparatus comprising:
- first processing means for use by the first party;
- second processing means for use by the second party, the second processing means being beyond control of the first party;
- interface means between the first processing means and the second processing means;
- key generation means for generating a secret key and a corresponding public key for the second party;
- means within the first processing means for randomly transforming signals representative of the information to be certified, into a vector of numbers, such that the first processing means has access to a representation of at least one number in the vector of numbers, and the representation contains the information to be certified;
- means within the first processing means for computing challenge information;
- means within the first processing means for transmitting to the second processing means, signals representative of the challenge information;
- means within the second processing means for computing response information, based on at least the challenge information and the secret key;
- means within the second processing means for transmitting to the first processing means, signals representative of the response information;
- and
- means within the first processing means for computing, based on at least the received response information, a digital certificate corresponding to the vector of numbers.
An apparatus for a first party which knows a first representation, where a first representation is a representation of at least one number in a vector of numbers with respect to a first function, to transmit to a third party a signal constituting a second representation, where a second representation is a representation of a second function of the at least one number in the vector of numbers with respect to a third function, the first party having previously generated a signal representative of a digital certificate corresponding to the vector of numbers with respect to a public key of a second party, the apparatus comprising:
- first processing means for use by the first party;
- second processing means for use by the third party;
- interface means between the first processing means and the second processing means;
- means within the first processing means for transmitting to the second processing means, signals representative of the vector of numbers and the corresponding digital certificate;
- means within the first processing means for computing, in response to challenge information, response information based on at least the challenge information and the second representation;
- means within the first processing means for transmitting to the second processing means, signals representative of the response information;
- and
- means within the second processing means for verifying that the digital certificate corresponds to the vector of numbers with respect to the public key and that the response information corresponds to the challenge information, the second function of the at least one number in the vector of numbers, and the third function.
An apparatus for a first party to have information certified by a second party by generating a signal representative of a digital certificate corresponding to a vector of numbers, wherein the signals representative of the vector of numbers and the digital certificate are hidden from the second party, yet the second party is ensured that the information to be certified is contained in a representation known by the first party of at least one number in the vector of numbers with respect to a first function, and then to transmit to a third party a signal constituting a representation of a second function of the at least one number in the vector of numbers with respect to a third function, the apparatus comprising:
- first processing means for use by the first party;
- second processing means for use by the second party and beyond control of the first party;
- third processing means for use by the third party;
- first interface means between the first processing means and the second processing means;
- second interface means between the first processing means and the third processing means;
- key generation means for generating a signal representative of a secret key and a corresponding public key for the second party;
- means within the first processing means for randomly transforming signals representative of the information to be certified, into a vector of numbers, such that the first processing means has access to a first representation, where a first representation is a representation of at least one number in the vector of numbers with respect to the first function, and the first representation contains the information to be certified;
- means within the first processing means for computing first challenge information;
- means within the first processing means for transmitting to the second processing means, a signal representative of the first challenge information;
- means within the second processing means for computing first response information based on at least the first challenge information and the secret key;
- means within the second processing means for transmitting to the first processing means, a signal representative of the first response information;
- means within the first processing means for computing, based on at least the first response information, a digital certificate corresponding to the vector of numbers;
- means within the first processing means for transmitting to the third processing means, signals representative of the vector of numbers and the digital certificate;
- means within the first processing means for computing, in response to second challenge information, second response information based on at least the second challenge information and a second representation, where a second representation is a representation of the second function of the at least one number in the vector of numbers with respect to the third function;
- means within the first processing means for transmitting to the third processing means, a signal representative of the second response information;
- and
- means within the third processing means for verifying that the digital certificate corresponds to the vector of numbers with respect to the public key and that the second response information corresponds to the second challenge information, the second function of the at least one number in the vector of numbers, and the third function.
Dependencies are inferred from the claim text.