Equihash is a Proof-of-Work algorithm, based on a generalization of the Birthday problem which finds colliding hash values. It was designed to be memory-hard; more specifically, the bottle-neck for parallel implementations of Equihash solvers would be memory bandwidth.

This crate implements Equihash as specified for the Zcash consensus rules. It can verify solutions for any valid (n, k) parameters, as long as the row indices are no larger than 32 bits (that is, ceiling(((n / (k + 1)) + 1) / 8) <= 4).

References

• Section 7.6.1: Equihash. Zcash Protocol Specification, version 2020.1.10 or later.
• Alex Biryukov and Dmitry Khovratovich. Equihash: Asymmetric Proof-of-Work Based on the Generalized Birthday Problem. NDSS ’16.