Geheimübertragungsverfahren und Geheimübertragungseinrichtung

摘要

A cryptographic communication method comprises a step for carrying out cryptographic communication between a sending station (1A, 1B, 1C) and one or more receiving stations (2A, 2B, 2C) by using (1) a ciphertext (C) formed by encrypting a unit of sending information under the intervention of at least a cryptographic key (K) and (2) key-distribution-information (Y) produced by using at least the ciphertext (C), receiving station's public information, and randomized information (r, r1) generated in the sending station (1A, 1B, 1C).