Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.

Abstract: The present invention relates to digital signature operations using public key schemes in a secure communications system and in particular for use with processors having limited computing power such as ‘smart cards’. This invention describes a method for creating and authenticating a digital signature comprising the steps of selecting a first session parameter k and generating a first short term public key derived from the session parameter k, computing a first signature component r derived from a first mathematical function using the short term public key, selecting a second session parameter t and computing a second signature component s derived from a second mathematical function using the second session parameter t and without using an inverse operation, computing a third signature component using the first and second session parameters and sending the signature components (s, r, c) as a masked digital signature to a receiver computer system.

Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.

Abstract: A system and method are provided for enabling a symmetric key to be derived, the method comprising: obtaining a plurality of key parts, wherein the plurality of key parts when combined equal the symmetric key; encrypting a first of the key parts using a first cryptographic algorithm to generate a first encrypted value; encrypting one or more remaining key parts of the plurality of key parts using respective cryptographic algorithms to generate one or more additional encrypted values, wherein each key part encrypted is encrypted using a different cryptographic algorithm; and providing the first encrypted value and the one or more additional encrypted values to an other entity to enable the other entity to derive the symmetric key.

Abstract: A method for communicating information between at least a pair of correspondents, the method comprising the steps of each of the correspondents selecting a plurality of cryptographic algorithms known to each of the correspondents. One of the correspondents applies the algorithms in a predetermined manner to a message for producing a set of processed information. The set of processed information is transmitted to the other correspondent. The other correspondent applies complimentary operations of the cryptographic schemes in accordance with the predetermined manner for deriving information related to the message from the processed information.

Abstract: A method of determining the integrity of a message exchanged between a pair of correspondents. The message is secured by embodying the message in a function of a public key derived from a private key selected by one of the correspondents. The method comprises first obtaining the public key. The public key is then subjected to at least one mathematical test to determine whether the public key satisfies predefined mathematical characteristics. Messages utilizing the public key are accepted if the public key satisfies the predefined mathematical characteristics.

Abstract: The present invention relates to digital signature operations using public key schemes in a secure communications system and in particular for use with processors having limited computing power such as ‘smart cards’. This invention describes a method for creating and authenticating a digital signature comprising the steps of selecting a first session parameter k and generating a first short term public key derived from the session parameter k, computing a first signature component r derived from a first mathematical function using the short term public key, selecting a second session parameter t and computing a second signature component s derived from a second mathematical function using the second session parameter t and without using an inverse operation, computing a third signature component using the first and second session parameters and sending the signature components (s, r, c) as a masked digital signature to a receiver computer system.

Abstract: A method of determining the integrity of a message exchanged between a pair of correspondents. The message is secured by embodying the message in a function of a public key derived from a private key selected by one of the correspondents. The method comprises first obtaining the public key. The public key is then subjected to at least one mathematical test to determine whether the public key satisfies predefined mathematical characteristics. Messages utilizing the public key are accepted if the public key satisfies the predefined mathematical characteristics.

Abstract: The present invention relates to digital signature operations using public key schemes in a secure communications system and in particular for use with processors having limited computing power such as ‘smart cards’. This invention describes a method for creating and authenticating a digital signature comprising the steps of selecting a first session parameter k and generating a first short term public key derived from the session parameter k, computing a first signature component r derived from a mathematical function using the short term public key, selecting a second session parameter t and computing a second signature component s derived from a second mathematical function using the second session parameter t and without using an inverse operation, computing a third signature component using the first and second session parameters and sending the signature components (s, r, c) as a masked digital signature to a receiver computer system.

Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.

Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.

Abstract: The present invention relates to digital signature operations using public key schemes in a secure communications system and in particular for use with processors having limited computing power such as ‘smart cards’. This invention describes a method for creating and authenticating a digital signature comprising the steps of selecting a first session parameter k and generating a first short term public key derived from the session parameter k, computing a first signature component r derived from a first mathematical function using the short term public key, selecting a second session parameter t and computing a second signature component s derived from a second mathematical function using the second session parameter t and without using an inverse operation, computing a third signature component using the first and second session parameters and sending the signature components (s, r, c) as a masked digital signature to a receiver computer system.

Abstract: A method of providing improved security in a communication system used to transfer information between at least a pair of correspondents. The communication between the correspondents generally comprises steps of generating key pairs in accordance with the arithmetic properties of a chosen algorithm, communicating one of the keys, being a public key, to the other party by way of a certificate, generation and transmission of a signature using a private key of the key pairs by one of the correspondents and transmitting the signature to the other correspondent and verification of the signature by the recipient. The invention provides for the additional step of verifying the public key conform to the arithmetic properties dictated by the requirements of the selected algorithm.

Abstract: A digital signature verification protocol utilises a pair of signature components incorporating a pair of private keys, one of which is a long term key and the other of which is a short term key. The long term key is applied to one of the signature components to reveal the short term key. The short tern key is then used to compute a value of a signature component contained in the signature. If the computed value and received values agree then authenticity is verified.

Abstract: A method of determining the integrity of a message exchanged between a pair of correspondents. The message is secured by embodying the message in a function of a public key derived from a private key selected by one of the correspondents. The method comprises first obtaining the public key. The public key is then subjected to at least one mathematical test to determine whether the public key satisfies predefined mathematical characteristics. Messages utilizing the public key are accepted if the public key satisfies the predefined mathematical characteristics.

Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.

Abstract: A method of authenticating a pair of correspondents C,S to permit the exchange of information therebetween, each of the correspondents having a respective private key, e, d and a public key, Qu, and Qs derived from a generator element of a group and a respective ones of the private keys e,d, the method comprising the steps of: a first of the correspondents C generating a session value x; the first correspondent generating a private value t, a public value derived from the private value t and the generator and a shared secret value derived from the private value t and the public key Qs of the second correspondent; the second correspondent generating a challenge value y and transmitting the challenge value y to the first correspondent; the first correspondent in response thereto computing a value h by applying a function H to the challenge value y, the session value x, the public value an of the first correspondent; the first correspondent signing the value h utilizing the private key e; the first correspondent

Abstract: A digital signature verification protocol utilises a pair of signature components incorporating a pair of private keys, one of which is a long term key and the other of which is a short term key.

Abstract: A digital signature verification protocol utilises a pair of signature components incorporating a pair of private keys, one of which is a long term key and the other of which is a short term key. The long term key is applied to one of the signature components to reveal the short term key. The short term key is then used to compute a value of a signature component contained in the signature. If the computed value and received values agree then authenticity is verified.

Abstract: A public key encryption system exchanges information between a pair of correspondents. The recipient performs computations on the received data to recover the transmitted data or verify the identity of the sender. The data transferred includes supplementary information that relates to intermediate steps in the computations performed by the recipient.