0.1.0 • Published 5 years ago

raffler v0.1.0

Weekly downloads
2
License
MIT
Repository
github
Last release
5 years ago

Raffler

Raffler is an algorithm to select a winner from a provably fair source of randomness.

The Algorithm

The algorithm is as follows:

  • Prior to starting, create an ordered list of participants (L_0)
  • Select some random string S_0 from an unbiased source of randomness
  • For each prize n, (n = 1, 2, ..., N):
    • Calculate H_n = HMAC_SHA256(S_0, string(n))
    • Interpret H_n as a integer Z_n
    • The winner is Z_n mod length(L_(n-1))
    • Remove the winner from the list to get L_n

Some things to point out:

  • There are no special requirements for the list. The order doesn't matter. You could use the names of the participants in some lexicographical order agreed upon beforehand, for example
  • A good source of randomness could be the hash of the first blockchain block generated after the submission deadline
0.1.0

5 years ago