Various applications of digital signatures such as document signing/timestamping are intended to be verifiable in the long term, as many critical documents such as contracts can be needed as a reference in ten, twenty, even thirty years time. Current signature schemes used in existing solutions are not secure in the long-term, as they are insecure once powerful quantum computers are available. However, at the moment, existing software is not yet supporting other digital signature schemes that offer resistance against quantum attackers.
Together with our partners at pqCee, based in Singapore, we developed a solution that can offer on-demand quantum resistance for existing (and traditionally insecure) digital signature schemes. By non-invasively augmenting the key generation of the existing scheme, we can provide an optional quantum-safe proof of key generation in addition to the traditional signature, and allow verifiers that want to ensure protection against quantum adversaries to do so.
Importantly, the additional post-quantum proof and verification in our solutions are completely optional and transparent to legacy clients. These clients can rely on the widespread support of traditional elliptic-curve based signature schemes to verify document signatures and timestamps as before, and only once the need for a quantum-safe verification arises, perform it in addition to the standard verification. This makes our solution an attractive option for a less-invasive migration strategy when considering post-quantum cryptography.
Learn more about the threat of quantum computers and post-quantum cryptography in our blog series.