Nonce
A bet counter that goes up by one for each wager on the same seed pair, so no two bets share a result.
Within a provably fair scheme, the nonce counts your bets. While the server seed and client seed stay the same, it begins at 0 (some casinos use 1) and goes up by one with each wager.
Its job
Take the nonce away and one seed pair would return an identical result on every bet. The counter gives each bet its own outcome while the whole series stays fixed by the seeds, which is what lets you rebuild any bet afterwards.
Audit checklist
- Each new bet should raise the nonce by exactly one. Skipped or repeated values can point to bets being dropped or replayed, and our audits look for exactly that.
- Find out if counting begins at 0 or 1; being one off is enough to make every verification fail.
Verifying a single bet
Four dice rolls in your history carry nonces 0 to 3. For the third roll, run HMAC-SHA256 with the server seed as key and "client seed:2:0" as message, turn the bytes into a float, and then convert the float into the roll.