Post
Topic
Board Announcements (Altcoins)
Re: [ANN][CHA] Chancecoin protocol, client, and coin for decentralized dice betting
by
PhantomPhreak
on 30/03/2014, 16:17:34 UTC
Having heard the community's concerns about block hashes being prone to manipulation, we have decided not to use block hashes to resolve bets. Rather, we will be using New York Lottery Quick Draw numbers to resolve bets.

New York Lottery Quick Draw

Quick Draw numbers are drawn every four minutes, every day of the week. The numbers are published online shortly after they are drawn. The drawing selects 20 numbers randomly from a pool of numbers 1 through 80, without replacement. In the newest version of the Chancecoin protocol, a bet seen in the blockchain will be resolved with the next available set of Quick Draw numbers. We use combinadics to convert these numbers to a random uniform variable, and use it to resolve the bet.

We have more updates coming this weekend.

If you can find a solution, it's much more elegant to use only the blockchain without external source.

If you use multiple blocks to generate a random number, it will already be more difficult to cheat.

For example :
- Use a block B1 to generate a number N1 between 1 and 100
- Use the block (B1-N1) to generate a number N2 between 1 and 100
- Use the block (B1-N1-N2) to generate a number N3 between 1 and 100
- ... repeat ...
- Use N100 as pseudo-random number.

This is just an example that requires more thought, but I think it is possible to make cheating difficult enough, for it is not profitable.

I like the idea of ​​having a random number generator in Counterparty. Potentially, this allows to play Poker, Blackjack, etc... And it would be a natural evolution of bets that already exist in Counterparty.
IMHO it is less cleaner to implement a new coin just for this functionality. The same question arises for the hundreds of LTC clones. Intuitively I think it is not good for LTC. But I think no one ever will know the real answer..



We considered a solution similar to this. The problem is that a devious gambler can always aggressively mine the last block that is to be used as a source of randomness to settle a particular bet, even if various other blocks are used in the randomness calculation. Hence we transitioned to the external source solution.

Yes you right! it seems that there is no solution not only using the blockchain since miners can potentially control precisely its content..

I think it may be possible to get around this, by having the values converge to a random value slowly over time.

How are you going to get the Quick Draw numbers in the protocol? Hard-code a URL into chancecoind?