PQC: Lattice-based signatures

Hash-based signatures, such as SHRINCS which feature 324-byte signatures, serve as a layer of abstraction over the underlying hash function, in this case, SHA256. This setup is inherently forward-compatible because if SHA256 becomes compromised or outdated, it can be replaced by a newer hash function like SHA3 without altering the layers built on top of it, such as SHRINCS. This characteristic makes hash-based signatures an attractive option for systems that require longevity and adaptability.

The use of hash-based signatures is particularly relevant in environments like Bitcoin, where there is significant resistance to rapid changes or radical new technologies. Advocating for conservative solutions, like the adoption of hash-based signatures, may therefore have a better chance of gaining widespread acceptance within such communities. This approach aligns with the strategic need to implement secure, yet minimally disruptive, updates to cryptographic practices in blockchain technologies.