Patent ID: 7203316
Filing Date: 2007-04-10
Classification: G06Q,G07F,H04L

Abstract:
1. A device for signing a message which is sent from a sender to a receiver comprising: a control center having a first memory, the control center including one input of a first one-time encrypter being connected to the first memory of the control center and another input being connected to a generator for a sequence number; a receiver having a second memory, each of the control center and the receiver storing a secret, common main key, the receiver comprising a signature checker having inputs connected to a message and to a signature of a data message block which has arrived via a secured transmission; a sender capable of receiving at least one pair of a signing key and the selected sequence number from the control center, an output of the first one-time encrypter being connected to the sender via the secured transmission, the sender comprising, a signature generator provided in the sender, and having inputs connected to the output of the first one-time encrypter and to the message to be signed, and an output of the signature generator providing a signature and being connected to a device which assembles at least the signature and the message to form the data message block and whose output is connected to the receiver via the secured transmission; a second one-time encrypter provided in the receiver, the second one-time encrypter having inputs connected to the second memory of the receiver for the secret main key and to means for determining a sequence number for the received data message block, the second one-time encrypter forming a check key; the signature checker being configured to receive an output of the second one-time encrypter; the check key and the determined sequence number being used to form a calculated signature for comparison to the signature of the data message block; and wherein the control center, the receiver, and the sender are individual and separate one from the other.