1G/ Fair Dice Roll’s in On-Line Game’s using Blockchains

From IIW

How to achieve fair dice rolls in online games


Wednesday 1G

Convener: Kazue Sako

Notes-taker(s): Tom Brown

Discussion notes, key understandings, outstanding questions, observations, and, if appropriate to this discussion: action items, next steps:


Currently, in most games, the outcome of roll is determined by servers


PRNG needs a seed. Propose to generate seed collaboratively by players and server


Server's portion of seed is not disclosed (until after the game) but hashed and committed to blockchain prior to receiving contribution of seed from players


After game, server's part of the seed is disclosed


Players cannot guess the next dice roll (although server can)


Design criteria: No limit to number of dice rolls after seed creation. Players can verify the outcome of dice rolls after the game


Usability: How easy can a player choose a random seed? Most players hate to see this information.


App has a review mode to see hash function outputs. Also has “verify-dice off-mode”


Blockchain as the third party.


Discussion: third party services like random.org do not seem to be verifiable