Issue One-shot signatures as post-quantum identity

Summary

As quantum computing advances, today's digital signatures, including elliptic curve cryptography and the RSA algorithm, are expected to become vulnerable to quantum attack. One-shot signatures are put forward as a promising post-quantum alternative for securing identity. They allow quantum keys that can be used only once, working on both conventional and quantum machines. Several hurdles remain, starting with the need to rebuild from scratch the secure hashing systems that turn inputs into unique digital fingerprints. Methods for concealing how quantum encryption works are also not yet settled, and making the approach practical for blockchain, decentralised finance and digital identity management will bring both challenges and opportunities.