A cryptographic system allows, in one exemplary use, a supplier to cryptographically transform a plurality of messages responsive to secret keys; the transformed messages to be digitally signed by a signer; and the signed transformed messages returned to the supplier to be transformed by the supplier, responsive to the same secret keys, in such a way that a digital signature related to each original message is developed by the supplier. One important property of these systems is that the signer ...

An improved blind signature system not requiring computation during blinding for anticipating which of a plurality of possible signatures will be made during signing, while still allowing the blinding party to unblind and recover the unanticipated kind of signature on what was blinded. An exemplary embodiment blinds by forming a product including a plurality of generators raised to powers normally secret from the signing party, and unblinds by forming a product with the multiplicative inverse of...

A signature feeder comprises an in-feed table for conveying signatures disposed in a stack adjacent one another and each in an almost vertical aspect to a signature separator operating to separate the signatures one at a time from the stack and transfer them to a signature elevator operating to raise them to an upper horizontal conveyor on which they are disposed in a partly overlapping shingle configuration. The signature separator comprises a plurality of sucker devices mounted on arms turnabl...

An arrangement for increasing the life, readability, and security of credit cards and similar elements having a portion to receive an authorized signature. Supplied with the card or thereon is a strip of transparent material having one adhesive surface, sized to cover the signature portion of the element. When this strip is applied to the element in overlay relation to the signature, it protects the latter from smudging and rubbing off, which occasionally occurs to the point that an alarm underl...

Signature verification where an image mosaic for a signature to be verified is stored in a memory and wherein a prototype feature set for said signature is stored in memory. Binary signals representative of the location and magnitude of positive and negative peaks in mosaic and the stroke character in the region of each of said peaks are generated. A two-dimensional feature set patterned after the prototype set is stored with the signals ordered in dependence upon the occurrence of the peaks in ...

According to the invention, the secret key of the claimant is constituted by k numbers s.sub.1, s.sub.2, . . . , s.sub.k with a low public exponent. The verifier draws k numbers a.sub.1, a.sub.2, . . . , a.sub.k in which the number of non-zero a.sub.i is below a given number p. The claimant or signatory calculates an answer involving an exponential product of form s.sub.i.sup.a.sbsp.1 with i between 1 and k. The verifier calculates another exponential product of form v.sub.i.sup.a.sbsp.1, where ...

A method for digitally signing a message by a tamper-resistant device to generate a digital signature. The method includes the step of hashing the message to form message bits; and encrypting with a private key the message bits, redundancy bits for the security of the signature, and auditing bits to form the digital signature for the message. The auditing bits provide an audit trail for the message. The auditing bits include one or more of the following categories: signature-packet version bits ...

1. The method of producing an electric signal corresponding to the underwr acoustic signature which would be generated by the movement of a certain sound source through a remote underwater environment which comprises preparing a recording at a substantially constant signal level of the acoustic output of said certain sound source in deep water far from shore, preparing a series of curves of the transmission characteristics of said remote environment for sound in selected consecutive frequency ba...

The pressure exerted while writing a signature is transduced to an electrical analog signal which is periodically converted to a binary coded number representing the average amplitude of the pressure between periodic samplings.

A system for determining an assigned classification for a set of physical events on a substrate. Sensors sense the physical events on the substrate and produce event data. A plug in rule module manager receives and manages any number of plug in rule modules. Each plug in rule module has an input, a local filter, an analyzer, and an output. The input receives the event data and confidence values from preceding plug in rule modules. The local filter analyzes the received confidence values from the...