🔗 An example of quantum-hard classically-implementable asymmetric crypto

NTRU is an open source public-key cryptosystem that uses lattice-based cryptography to encrypt and decrypt data. It consists of two algorithms: NTRUEncrypt, which is used for encryption, and NTRUSign, which is used for digital signatures. Unlike other popular public-key cryptosystems, it is resistant to attacks using Shor's algorithm and its performance has been shown to be significantly better. NTRU was patented but was placed in public domain in 2017, and can be used by software under the GPL.