International Association
for Cryptologic Research

The security of cryptographic primitives is an important issue. The Shor algorithm illustrates how quantum attacks threaten the security of these widely used primitives. Code-based cryptography is one of several approaches resistant to quantum attacks. To date, no attack has been able to break a code-based cryptosystem in polynomial time. Despite this level of security, these cryptosystems have not been considered for practical applications such as e-commerce, medical and industrial IoT, finance, blockchain, mobile services, and online banking. The main reason is the large public and private key sizes. This paper presents a new code-based cryptosystem based on inverse parity check matrices. The dual matrix provides both a parity check matrix transpose and a parity check matrix inverse. These are employed in the key generation, encryption, and decryption algorithms. The proposed scheme provides public and private key sizes smaller than the McEliece cryptosystem and has a higher level of security.