2 ms·
If you go by the usual, energy-wasting meaning of "proof of work" that is also the one relevant to the discussion (i.e., Bitcoin-style PoW which is described in
by c0742e9366 5y ago
If you go by the usual, energy-wasting meaning of "proof of work" that is also the one relevant to the discussion (i.e., Bitcoin-style PoW which is described in the article), then no.
- floatboth 5y agoso, it is proof of work, it's just not "a proof-of-work lottery"
- c0742e9366 5y agoYes, in the strict sense of the meaning. In general, the comparison of VDFs (a cryptographic building block) and Bitcoin-style PoW (a consensus mechanism) is not that useful. However, using a VDF as part of a consensus mechanism (see e.g., Chia) does not introduce an energy overhead. To demystify what a VDF is, consider the delay function (i.e., the majority of the work done to compute a VDF) used by the most prominent proposals: Let N = p*q be a product of two large primes (so an RSA modulus) and assume that the primes p and q have been immediately thrown away/forgotten after initialization. Then, computing f(x) = x^(2^T) mod N is believed (dating back to a paper by Rivest, Shamir and Wagner in 1996) to take T sequential steps provided that T is large enough. For a large T, the only feasible approach seems to be repeated squaring modulo N. That is, compute y = x^2 mod N, y' = y^2 mod N, ... for T times.