Is PrimeDice really (provably)fair?

[Stunna]

Stunna, your competitors (specifically JD and CR) don't get the same accusations. They are Provably Fair as far as players are concerned. I believe you can just simply use the same system and dooglus already gave open permission to copy his method.

This was the plan for the new site, there are still vulnerabilities with that method from what I can tell (please correct me if I'm wrong). I might not have an expert grasp on provably fair but couldn't a site using a system like JD's or CR's manipulate the sha 256 server seed hash to result in a loss streak for the player?

ex. A server seed hash could be placed that results in a loss streak or a loss given the site knows your client seed.

If the user didn't change their client seed frequently, wouldn't this be a possibility? If so what is the definitive advantage to that system and is there a way to improve on this? Our main motivation for changing our system will be instant verifiable results and ability to check them by running a terminal command but is there an advantage for the user in terms of fairness?

[1714935232]

1714935232

[Dabs]

ex. A server seed hash could be placed that results in a loss streak or a loss given the site knows your client seed.

Yes, that is true, but only if the server is allowed to generate their server side after knowing what the client seed is.

In both cases:

The server seed is created before the player can give their client seed. The server seed is hashed and shown to the player, so the player can verify at any time after a roll if it was fair or not. The player can verify that the server seed has not changed since it was created.

The server does not know the client seed until after it has created the server seed. The server therefor has no opportunity to compute or calculate a forced loss. It will simply calculate, whether that results in a loss or a win, fairly.

The order is important. Server creates server seed. Then player is allowed to create client seed or the player's deposit determines the client seed.

If the player creates the client seed first, then the server has an opportunity to attempt to manipulate future rolls.

If the seeds remain unchanged and the only variable left is predictable, such as an incrementing nonce, then both server and player can not cheat. The server can't change the outcome, the player does not know for sure, therefore the player can bet or gamble fairly.

If you need details, we can discuss over PM, but I think I already told you some time ago, I'll have to check.

(And oh, I still want to make a provably fair poker game, so ... PrimePoker looks good huh.)

[a1choi]

If the seeds remain unchanged and the only variable left is predictable, such as an incrementing nonce, then both server and player can not cheat. The server can't change the outcome, the player does not know for sure, therefore the player can bet or gamble fairly.

ah thanks dabs for saying this! i've been failing to clearly understand this and now it just seems trivial! why didn't i get it before =D

[Dabs]

You don't really get it until you do. And when you do, you wonder why you never got it until then.

Whoever takes my concept of provably fair card games (poker, blackjack, etc) is going to make a killing. I just wish I had my own dev or team and the capital to make one myself.

I've also suggested to doog before, since I liked his version or implementation, to include a "dice on crack" version, where one can auto-bet 10k times and the whole sequence is pre-programmed (martingale or whatever) and the whole sequence is still provably fair from start to finish, based on the player's rules.

I'd certainly want to throw a bitcoin into gambling 10k rolls and finding out the result in 1 second.

I'm left to being a consultant or escrow and someone else will make all the money.

[cwil]

There's nothing wrong with PD's current implementation of a provably fair system.  The only criticism I see in this thread is that people don't use the system in any meaningful way and that somehow means PD is cheating.  If I could offer some criticism for off-chain provably fair systems in general, the use of a daily secret is unnecessary and counterproductive.  Satoshidice dice and similar games have an obvious need for a daily secret, and it makes sense in that context.  Off-chain games, however, can provide a hash of the next bit of data they intend to use to produce the next outcome.  An off-chain game with a provably fair system that relies on a daily secret makes it impossible to verify bets at run time for no good reason at all.  Stunna, unless you can come up with a good reason why a daily secret is better than random data generated per roll, I'd suggest you stay away from the implementation mistakes of your competitors.  Real time verification is a nice feature for people like me who are interested in automation.

[jambola2]

There's nothing wrong with PD's current implementation of a provably fair system.  The only criticism I see in this thread is that people don't use the system in any meaningful way and that somehow means PD is cheating.  If I could offer some criticism for off-chain provably fair systems in general, the use of a daily secret is unnecessary and counterproductive.  Satoshidice dice and similar games have an obvious need for a daily secret, and it makes sense in that context.  Off-chain games, however, can provide a hash of the next bit of data they intend to use to produce the next outcome.  An off-chain game with a provably fair system that relies on a daily secret makes it impossible to verify bets at run time for no good reason at all.  Stunna, unless you can come up with a good reason why a daily secret is better than random data generated per roll, I'd suggest you stay away from the implementation mistakes of your competitors.  Real time verification is a nice feature for people like me who are interested in automation.

Exactly.

All this entire accusation says is that PD is not fair if you don't change your seed. Well , duh.

[coincolonel]

There's nothing wrong with PD's current implementation of a provably fair system.  The only criticism I see in this thread is that people don't use the system in any meaningful way and that somehow means PD is cheating.  If I could offer some criticism for off-chain provably fair systems in general, the use of a daily secret is unnecessary and counterproductive.  Satoshidice dice and similar games have an obvious need for a daily secret, and it makes sense in that context.  Off-chain games, however, can provide a hash of the next bit of data they intend to use to produce the next outcome.  An off-chain game with a provably fair system that relies on a daily secret makes it impossible to verify bets at run time for no good reason at all.  Stunna, unless you can come up with a good reason why a daily secret is better than random data generated per roll, I'd suggest you stay away from the implementation mistakes of your competitors.  Real time verification is a nice feature for people like me who are interested in automation.

Exactly.

All this entire accusation says is that PD is not fair if you don't change your seed. Well , duh.

I think it is not that easy to change the algorithm in ongoing system (please correct me if I'm wrong). I also believe if PD is trying to 'guess' your next move based on previous move, it can be a backfire to the site because player will be able to guess the site's move as well. The best move for PD should always be a random number, because even with this weakness, PD still does not know the bet amount. Hopefully I have correct understanding.

[CaMeRoNy]

Agreed that site is scum
stay away all

[SelbyTsang]

Agreed that site is scum
stay away all

That doesn't sound right from someone with "Trust: -6: -1 / +1(1) Warning: Trade with extreme caution!"

[dooglus]

If I could offer some criticism for off-chain provably fair systems in general, the use of a daily secret is unnecessary and counterproductive.

It's like this:

PrimeDice: changes secret every roll - makes the user have to do much work to verify (too hot)
CoinRoll: changes secret once per day - makes the user wait too long to verify (too cold)
Just-Dice: changes secret when the user asks to change it (just right)

It's like Goldilocks up in here.

[a1choi]

If I could offer some criticism for off-chain provably fair systems in general, the use of a daily secret is unnecessary and counterproductive.

It's like this:

PrimeDice: changes secret every roll - makes the user have to do much work to verify (too hot)
CoinRoll: changes secret once per day - makes the user wait too long to verify (too cold)
Just-Dice: changes secret when the user asks to change it (just right)

It's like Goldilocks up in here.

with a min of 10 rolls per secret!     why is that? why do you limit it?  not that i mind.

[kuverty]

This thread is simply stupid for the most part. Why post such accusations without anything to back it up? If these accusations are correct, it would not have been too difficult to actually gather some evidence that would show some statistically interesting bias. Of course it can be frustrating to lose money and if you have a 20-roll losing streak, it is very human to try and find a culprit elsewhere.

That is valid though, that the site could just choose when the user wins or not and a site operator would be tempted to manipulate the result if someone is about to win big (hundreds of BTC for example). I do not see any reason to believe PD is cheating now though but of course it should now be changed, for example to the Just-Dice system which works really well.

Anyway, especially after this thread, no new gaming sites that employ a system like this should be avoided until they correct this obviously bad practice. It is only a matter of time someone cheats big. Good work for putting these "provably fair" systems under scrutiny.

[dooglus]

no new gaming sites that employ a system like this should be avoided until they correct this obviously bad practice

I would suggest exactly the opposite.

all new gaming sites that employ a system like this should be avoided until they correct this obviously bad practice

[Namworld]

This isn't really an accusation that PrimeDice is cheating. Just that their system is a bit flawed. More that we can't know by default if results are fair unless one changes his own seed for every roll. It can be provably fair, but only in that specific circumstance. A provably fair system shouldn't have a cheating possibility under any scenario, regardless of if the site cheats or not.

PrimeDice: changes secret every roll - makes the user have to do much work to verify (too hot)
CoinRoll: changes secret once per day - makes the user wait too long to verify (too cold)
Just-Dice: changes secret when the user asks to change it (just right)

Dooglus, I don't think Coinroll is "too cold". Doesn't JD provides a default client seed too? Need to change client seed once, good to go forever. Much better.

Fixed daily secret for everyone seems good. It makes it pretty much impossible to cheat players under any circumstances. Most people don't need to verify and won't do it immediately after betting or won't do it at all. The daily secret cannot be be changed without altering all previous bets for that day. Finding a secret that match all bets for the day would simply be impossible. We also don't provide a default client seed, avoiding any possible claim we chose one with lucky numbers favorable to the house for the current day/server secret. We simply use the user's deposit tx ID. Put simply, Coinroll users don't need to do anything to be on the safe side and we don't have to provide a default secret.

The whole point is everyone don't need to even verify and often most people won't. So archived bets are provided (not simply one by one bet lookup on the website, downlaodble archives for easy checking with script). Pretty much anyone can just run a check on the archives and report anything suspicious. When people are playing, they want results instantly. Verifying bet timing isn't as important. If you want to check that, you can always check bets in batch later. Being able to verify them immediately wouldn't change their loss/win. No new information. Just not as time sensitive, unlike betting which needs to be instant, so Coinroll use that system. Just seems like a stronger provably fair system. We have yet to see any demand for instant verification.

[CoinCollect]

This site is scum.

[Nagato4]

This site is scum.

Would you mind telling us a little bit details what happened? 

[CoinCollect]

This site is just scum, i have deposit money and bever recieved. contact stunna and he did not help.
fuck primcedice

[unknow3nkid]

Just dice is where its at, best site ever.
RIP ;(

[galbros]

This site is just scum, i have deposit money and bever recieved. contact stunna and he did not help.
fuck primcedice

First, this thread is about provably fair, not deposit complaints.

Second, your complaint would have a lot more validity if you posted some images of your messages sent to and received from Stunna.  Just like he did here.  Which, interestingly, seems to be about your issue and him resolving it.

Finally, given how many users Primedice has I doubt they are screwing them out of deposits.  There is no need to do that, they win plenty plenty with their 1% edge.

Good Luck.

[Ejaculation]

This site is scum.

Why did you have to bump this thread -_-