Topic: If I wanted to start a Bitcoin casino... [will pay for help] - page 2. (Read 9109 times)

card based games: the card order is hashed prior to a game, and the hash is presented to the user
dice/roulette: hash of the outcome is presented to the user prior to the game
the data in each of the cases probably will have to be padded with some random data to prevent someone from bruteforcing the results to gain an advantage.

Don't even need to try, https://en.wikipedia.org/wiki/Martingale_%28betting_system%29

After some thinking, I came up with this. It should be cheat-proof from both parties, and is fully auditable.

Every day, generate a table with n + 1 columns (n being the number of "wheels" in the slot machine), and a very large number of rows. Now fill all of it with random numbers. Those random numbers will represent the outcome of a slot machine play. For example, column 1 will represent the position of where the first "wheel" will land, the second will represent the second "wheel", etc.. Now, hash each row's data + some random padding, and save the hash in the last column. Now publish the table, with only the last column. When a user plays, he/she will be allowed to choose from any hash he/she wants. After 36 hours, publish the entire table. Now anyone can audit the table to ensure that the game is indeed fair, and since another table has been generated for the day, no one can cheat. The casino can't cheat in this case because the hash has already been published prior to play, so there's a very low chance the results has been tampered with.

I think much depends on the game.

If it is a roulette - you could show the hash of the salted outcome before players make bets and show the sault after the game ends.

Many games could be secured this way (use pregenerated random values show the hashes of game states before players make decisions).

However if players play against each other and they have something to hide from each other (like in poker) then it is harder (since casino owner potentially knows the cards of other players and it gives him/her possibility to play against them).

Trusting online casinos is very very hard. The temptation to "adjust the rules" to benefit the casino is too high.

For example, in a physical casino a 6 deck blackjack is shuffled when the stack is about 2/3 or 3/4 exhausted. Online casinos typically shuffle the cards after every deal. This reduces player edge and prevents counting for example.

Online slot machines are far worse. They can easily payout only on small bets or adjust the payout rate by the hour.

If you want to prove that your casino is on the up-and-up, you may have to do the following:

In realtime, show every btc going into the system and going out for each slot, BJ or other game. Sort of like a time and sales display on a trading platform. So for example, if I bet 1 BTC on a BJ hand, it prints the entry right away. When its paid out, it prints that right away as well.

BJ   Table3   1QaZxSw2    1BTC      bet
BJ   Table3   1QaZxSw2    1.5BTC   win

Player's eyes will monitor the tables they are in and over time, sufficient trust should develop. Casinos typically can afford to be honest, since games are designed to benefit the casino in the long run. All players will lose in the long run but sufficient number have to win occasionally to keep the game attractive.

You can also publish your algorithms and source code and have their md5 hash published. Independent auditors can analyze your code to make sure its fair, etc.

I would recommend reading about how physical casinos prove that they are fair.

Absolutely.  If there is a way to have a 3rd party approve it that would be the most legit way to do things.   I want to do this right.

Will your casino be security validated by a approved 3rd party ?

Its fairly easy to fire up a few games, but just like when secondlife was young, without validation, the users dont know how fair the games really are.

ie. its pretty easy to detect a user using double bet attack, and let them succeed a few times, before locking them in for a 50x lost bet.

In the real world slot machines are required to display their current payout pct, and it needs to be above xx%, but still if noone verifies the machine/script, you could print 99% payout pct and in fact payout less than that.

If users cannot trust that they are being treated as fairly as any other real life casino, I dont see it taking off bigtime.

So basically I have the site Bitcoin Mafia.

I want to make it so that people can have a Bitcoin balance displayed on the site alongside the Mafia Cash so that people can purchase lottery tickets using bitcoin for a bitcoin lottery plus go to the casino and play actual bitcoin roulette to win/lose bitcoin. 

I could probably implement this in a simple way but I don't know how to secure the code and make it so that it's safe for everyone.

Sites like bittleships and luckycoin casino make it look so easy to deposit/spend/earn/withdrawl bitcoin, and I was wondering if someone would help me set that up.

I have other ideas for uses of Bitcoin in the game, but I'll leave it at that for now and see what you guys think.