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 lo 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: The public key, either short term “session” key or long term key, is generated by combining a pair of components. A first component is obtained by utilizing an integer with a relatively low Hamming weight as an exponent to facilitate exponentiation. The second component is a precomputed secret value that is of the form resulting from the exponentiation of the generator of the group element by an integer that has the requisite Hamming weight. The two components are combined to provide the public key and the two exponents combined to provide the corresponding private key.

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 and apparatus for cryptographically transforming an input block into an output block. The input block has a first block size and is partitionable into a plurality of input subblocks having a second block size that is a submultiple of the first block size. To encrypt or decrypt, the input subblocks are passed through respective first substitution functions controlled by one or more keys to generate a first plurality of modified subblocks. The first plurality of modified subblocks are then passed through a mixing function to generate a second plurality of modified subblocks, each of which depends on each of the first plurality of modified subblocks. Finally, the second plurality of modified subblocks are passed through respective second substitution functions controlled by one or more keys to generate a plurality of output subblocks that are combinable into an output block.

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 conforms to the arithmetic properties dictated by the requirements of the selected algorithm.

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 generating a private key for use in a public key data communication system implemented between a pair of correspondents is disclosed. The method comprises the steps of generating a random number for use as a private key and testing the number against a predetermined set of criteria The criteria are chosen to determine the statistical randomness of the number. The random number is utilized as a key upon satisfying the criteria.

Abstract: An integer for a private key is generated utilising a pair of components that are combined in a fixed predictable manner. The first component is generated from a sequencer such as a counter that generates non-repeating distinct value and the second component is generated in a random manner. By combining the components the integer has a unique and unpredictable value.

Abstract: A support structure for thin screenplates utilized for fine screens in Fibresaving applications for pulp fiber suspensions or the like wherein a support structure having a screen support in minimum screen contact positioned by a support reinforcement and positioning device, assembled to form an integral structure which reduces the stresses and deflections in the thin screenplates occurring in operation.

Abstract: A support structure for thin screenplates utilized for fine screens in Fibresaving applications for pulp fiber suspensions or the like wherein a support structure having a screen support in minimum screen contact positioned by a support reinforcement and positioning device, assembled to form an integral structure which reduces the stresses and deflections in the thin screenplates occurring in operation.

Abstract: A method and apparatus for multi-channel control of a multiple input, multiple output, servo-driven plant utilizes finite impulse response (FIR) filters to model the inverse of the plant. Each channel includes a servo FIR filter that generates a servo command to drive the plant's servo controller, a valve current FIR filter that bypasses the PID stage of the servo controller to avoid undesirable effects of the PID loop, and a cross FIR filter for each of the remaining channels that compensates for physical coupling in the plant between the channels. The servo FIR filter is calculated by an adaption routine that involves applying an identification signal to the plant, applying the plant's response to the filter and then updating the filter's coefficients using the error that exists between the identification signal and the filter output.

Abstract: A system for authenticating a user located at a requesting node to a resource such as a host application located at an authenticating node using one-time passwords that change pseudorandomly with each request for authentication. At the requesting node a non-time-dependent value is generated from nonsecret information identifying the user and the host application, using a secret encryption key shared with the authenticating node. The non-time-dependent value is combined with a time-dependent value to generate a composite value that is encrypted to produce an authentication parameter. The authentication parameter is reversibly transformed into an alphanumeric character string that is transmitted as a one-time password to the authenticating node. At the authenticating node the received password is transformed back into the corresponding authentication parameter, which is decrypted to regenerate the composite value.

Abstract: The invention described herein suggests methods of cryptographic key management based on control vectors in which the control vectors are generated or derived internal to a cryptographic facility implementing a set of cryptographic operations. The methods of alternate control vector enforcement described in the present application provide a high-integrity facility to ensure that cryptographic keys are used in a manner consistent with the type and usage attributes assigned to the keys by the originator of those keys. Since the control vectors are generated or derived internal to the cryptographic facility on the basis of data contained in each cryptographic service request to the cryptographic facility, control vectors need not be stored or managed outside the cryptographic facility.

Abstract: A system and method provide a security agent, consisting of a monitor and a responder, that respond to a detected security event in a data communications network, by producing and transmitting a security alert message to a network security manager. The alert is a security administration action which includes setting a flag in an existing transmitted protocol frame to indicate a security event has occurred. The security agent detects the transmission of infected programs and data across a high-speed communications network. The security agent includes an adaptive, active monitor using finite state machines, that can be dynamically reprogrammed in the event it becomes necessary to dynamically reconfigure it to provide real time detection of the presence of a suspected offending virus.

Abstract: A method and system are disclosed for the implementation of a weakened privacy channel. This is achieved through use of a weakened symmetric cryptographic algorithm called commercial data masking. The masked text is created from clear text at one system and may to transported electronically to another system where the masked text may be unmasked to produce the clear text. The reason to use the commercial data masking algorithm for data privacy is that it is exportable to organizations to which products which contain the Data Encryption Algorithm when used for data privacy are not exportable. In addition, a method and system is disclosed by which the key when used for commercial data masking may be transformed into a key that may be used with the Data Encryption Algorithm.

Abstract: A method and system are disclosed for securely distributing a plurality of software files from a software distribution processor to a user processor, while selectively enabling the user processor to only use a subset of a lesser plurality of the software files. This is achieved by employing a customer key which includes a clear customer number and a derived portion derived from the customer number. The customer key is transformed into a second customer key which serves as a key expression for encrypting a file encryption key specifically intended for a respective one of the plurality of files. A plurality of software files can be stored together, for example on a CD-ROM, with each file encrypted under a corresponding file encryption key. The CD-ROM can be distributed to many user processors. When a specific user processor needs to run one of the software files, a request will be transmitted from the user processor to the software distribution processor.

Abstract: In a cryptographic module, a User Defined Function (UDF) facility is provided which provides users with the capability of defining and creating custom functions to meet their cryptographic processing needs. The cryptographic module is contained within a physically and logically secure environment and comprises a processing unit and memory connected to the processing unit. The memory includes code for translating User Defined Functions (UDFs) into a machine-readable form and at least one command for operating on the UDFs. The UDFs are loaded into and executed in the secure area of the cryptographic module without compromising the total security of the transaction security system.

Abstract: A computer apparatus, program and method function in a data processing system to replicate a cryptographic facility. The system includes a first cryptographic facility containing a portable part which personalizes the first cryptographic facility. The system also includes a second cryptographic facility which is linked to the first cryptographic facility by a public key cryptographic system. The portable part of the first cryptographic facility is encrypted and transferred to the second cryptographic facility, where it is decrypted and used to personalize the second cryptographic facility to enable replication of the first cryptographic facility. In one application, personalization of the second cryptographic facility can be in response to the detection of a failure in the first cryptographic facility. In another application, multiple cryptographic facilities can be brought on-line for parallel operation in the data processing system.

Abstract: A cryptographic facility implements a multiple key part import procedure. The installation manager can verify that a key part has been correctly entered and has not been compromised. The security requirement for the procedure is that no single party can subvert the system security by misusing the procedure. This is accomplished by the use of a control-vector-dependent verification pattern to indicate that each key part has been accepted by using the proper control vector and the use of different key switch positions to specify whether the key part is a master key part or an operational key part and whether the key part is a first part or a subsequent key part. The apparatus provides an automatic reset of the key part register at the completion of each key-entry instruction so that each key part can be imported only once. This prevents the same key part from being imported twice as different key part types. The apparatus also prevents a key part from being combined with itself to create a known key.