Post-quantum digital signature system for preserving integrity, authenticity and disallowing repudiation of digitally transmitted message and method thereof

Abstract

The present invention relates to an improved post-quantum cryptographic system for preserving integrity, authenticity and disallowing repudiation by the sender of an electronic message in a transaction over a data communication system between a sender and a recipient through a certifying authority. The post-quantum cryptographic system preferably comprises a cryptographic unit (100) comprising a memory (200) having a key generation module (201) and a cryptographic module (202) and a processor (300). The key generation module (201) is configured for generating private seeds having a minimum length of 128 bits either from a true random number generator or a pseudo random number generator and comprises an algorithm for generating public-private key pairs which sources from the Modular Reduction Problem, whilst a trapdoor associated thereof are random elements from a public prime list. The cryptographic module (202) is configured for digitally signing the electronic message and verifying digital signature of the electronic message, which sources from the Modular Reduction Problem, wherein the digital signature algorithm employs a hash function for generating a hash value from the electronic message.