Online poker sites use anti-bot measures similar to what you re describing. I recommend the series of articles How I Built a Working Poker Bot for a good overview of how these systems work, and how they are defeated.

I agree with the others who said that there s not much you can do to stop the most dedicated cheaters, but you might be able to prevent casual cheating. (The problem with that, of course, is that then the dedicated cheaters will rule your site.)

I can t see that there is anyway to prevent someone to using a chess engine to assist them, unless you can observe the player.

You might have some luck protecting against fully automated bots, though.

Many chess computers work to formulas and end game books, so they will often play the same move in a particular situation. You could run users game history through a variety of chess computers and see if the users chosen moves after the opening moves have correlation with how the various chess computers play. This could be used to highlight users that are using chess computers.

Sites like chesscube monitors you for some time if you comes under the radar of suspicion. They monitor how much time you are taking for hard moves and relative simple moves. If there isn t some serious difference, they may conclude you are cheating. Also I believe they implement some method to check the shifting between windows, however I m not sure about what they use for it. But I personally know guys who had been banned. So their method is pretty good.

I second what JesperE say, You have to monitor the guy for sometime before arriving on an opinion.

As a holder of a similar site, I would suggest just to let them be. If you are not intended to monetize the bets, the cheaters will move to their level of Chess program that plays for them, and fall off. Best practice is to keep several player rooms according to level, thus cheaters will even be welcomed, allowing strong players to reach out to higher level, and adding practice to rookies.

Technically, there s nothing I can think of you can do.

Socially, there s a lot. For example, all of the online board game servers I ve seen make very public the user s win/loss record, and compute the user s rank from that. Doesn t that just encourage people to want to win? Instead, I d record all games, but not present a win/loss record anywhere (does anybody at a real chess tournament know how many games they ve won/lost ever?). Make rank a user-entered number, used for the purposes of finding an appropriate partner only, so simply showing rating of 5000 is meaningless. If you need to have some kind of user rating , then add a commentary system, to let users comment on moves of other people s games, and then let other users rate the comments. Commentary is one thing I haven t seen computers do intelligently yet, so it s something you can probably assume comes from a real person.

I would suggest having them have a webcam behind them but slightly to the left so you could see if they were pulling up another window such as a chess engine, as a chess master (rated 5th in Canada) I was baffled at how I was losing against players so frequently on the internet (the high timed games, ironically whenever I beat an engine user I was immediately accused of cheating) yet I would never lose to anyone except those top players in Canada s country tournaments where the best of the best were there. The difference? Those people couldn t use a chess engine while I was staring them down as they made their move. All you people that cheat, I fail to see the point, you aren t winning, you aren t furthering yourselves in the games, all you are doing is wasting your time mimicing a computer, you aren t even analyzing the board! I only play 5 minute games and blitz because these cheaters can t efficiantly use their engines in such a short time period but this is not how chess is supposed to be played you are supposed to think about you moves.

Nothing effective.

Depending on how much access you have to the computer the user is playing on, you can scan his process list for known chess programs and kick him if you see one... but there is no guarantee that he is actually using it in the manner you describe, and he can always use it on a separate computer if he has duel displays or a KVM.

Cheaters will find a way to cheat.

The good news in this case, is that the computer programs for chess are reasonably beatable unless they are running on some serious hardware.

Good luck.

You can theoretically prevent the automatic relaying of moves (but doing it manually is not much of an obstacle unless you re playing speed chess), perhaps even prevent any chess programs to be run on the same machine. But IMO that s a waste of effort, because you ll never be able to prevent people from running a chess program on a different machine sitting next to them.

Im not very familiar with this enviroment. But maybe CAPTCHA would help stop automated robots. You could also generate statistics for your users (games won/lost/average speed to move, etc). The first movements should be fast, but later on the movements should be slower as complexity increases. so you can highlight cheaters, monitor them and maybe ban their accounts as Wikipedia does with some editors. You could even make a point based system as stackoverflow does, to whitelist known good/clean players.

I cant see any way of stopping this from happening - pretty much whatever you do the cheater will still be able to manually "copy" the move that the other player has made (to another computer if necessary).

How about somehow using social mechanisms to discourage these sorts of players? Cheating in this way is obviously in itself fairly unrewarding in the long term for the cheater - if you can find and eliminate / safeguard any potential gain (for example ranked tournaments with prizes) that the cheater might be able to use this to explit against, then you should at least be able to keep the percentage of cheaters down allowing most other users to enjoy "genuine" chess games.

I don t know the specifics, but I m sure you could get statistics about the behavior of players that cheat this way--in other words, find things that the cheaters have in common (length of turns, consistency, etc) and have your application automatically find those and put a "red flag" on players that look suspicious. Then you can personally review them (or have someone else do it) and see if indeed they look suspicious. If so, ban them.

Other than that, there is really not much you can do unfortunately. The above suggestion is a lot of work, so unless you re willing to put in the hours to create such a system, I wouldn t even bother with it. Whatever barriers you put up, determined cheaters will get around them.

I have two accounts on chess.com. The first one i use to cheat. I have rybka deep 3 which is the most beastly chess program i know. On this account i have played 70games and lost 8times. 6 of those times are to time running out. The other two was from playing two GMs. I would never enter a tournament with it because thats just crossing the line for me but regular rated game i cheat like crazy. I don t do it because i want to win. I do it because i want to see who can beat this program. The two GMs that beat it. It was one of the greatest chess games ive ever seen. They never won after that and i played them a lot after that. I have another account which is my legit account that balances out my conscience. Im more in between beginner and intermediate. Anyways great players can tell when someone is using a comp program. Ive been accused like a dozen times for cheating because some of the moves rybka pulls are just straight godly. I have gotten banned once before on chess.com for cheating. It sucked cuz I had some epic games saved on there but on my new account that i have for about 3months now has not been banned. Maybe because the people i play see it as a challenge than them getting duped. IDK but ill soon start losing on purpose to fall under the radar xD. So if you want to catch a cheater ill say look for people with ridiculous stats like 80games, 9losses, 3draws with ratings of 2200+(If youre using the regular chess rating system).

There isn t much you can do to prevent cheating other than using correlative methods and a banhammer. You can make it very difficult for them to get a new account once they are banned or better yet just match them up against other cheaters transparently. Eventually they ll get bored. While it does depend on how much access you have, I ve seen some java applets that will effectively create a hash of hardware profiles similar to apples UDID, and then theres cookies. Matching banned account email hashes to strings in other login cookies wouldn t be too difficult either. Taking it to the next level, if you had an app running locally you could also peek at the process list. Looks like this might be a bit dated by now though.

The only solution is to show that cheating does not do anything beneficial for humanity and to show to cheaters that humanity is more important then some ego based reward they get from cheating. You cannot detect a computer vs human in all cases without putting them in a isolated room with no way to cheat. There are very good players, are they cheaters?

The reason there are cheaters is because society has allowed cheaters to exist and perpetuate and benefit.

Ask yourself, why does a person cheat? Self-worth? money?

When a society doesn t fulfill the needs that every human being needs the human beings find ways to do so.

e.g., if you are poor and can cheat at something(e.g., politics), become "wealthy", get a hot wife, famous, etc... then you are likely to do that.

In a perfect society everyone is equally wealthy and everyone works to help each other. There are no famous people because that creates an imbalance and everyone realizes that. There are no ugly or hot people because everyone is what they are. There are no fat people either because everyone works out to be healthy and not to be a drain on society(which makes them look better).

America and Christianity(and just about every other religion) have created a huge inversion of morality. By focusing on materialism, imaginary scenarios of life after death(Santa Clause and Tooth Fairy stuff just wrapped up in a guy named Jesus and a book instead of a Tooth).

The problems are fundamental and much more than chess and to solve the chess problem one must solve the fundamental problem. Society and humanity must change. Since this won t happen any time soon and is too complex a problem for 99.9% people to grasp(most are too busy reading their bible for answers that never work) the best thing to do for any individual that understands the consequences of cheating is to simply not cheat and life with the cheaters the best they can.

Don t go to the dark side and things will eventually get better. Cheaters cheat... they cheat each everyone, themselves, and life and there are consequences.

e.g., suppose you could divide the world up in to two groups. Cheaters and non-cheaters. You could isolate both. The cheaters would eventually die out because they don t do anything worth while. They are effectively parasites and need a host to life. Remove the host and they die(it doesn t happen in the real world because they can thrive and do quite well, because the non-cheaters are generally ignorant of the fact and unwilling to make hard choices. (e.g., if a husband is a cheater and the wife isn t, she usually stays with him rather than leaving him... or better yet, never marrying a cheater in the first place(which is hard but easier if Christianity didn t make it so hard).)

I ll give you an example: I used to play counter strike(a first person shooter) when it came out. There was obvious cheating going on and I knew it(it s impossible for humans to do certain things, just physics). I did research and found some bots and started cheating myself. When I suspected cheating I would use the bot. Guess what?!?! Sometimes I would lose! Bots are nearly perfect and instantaneous... yet I would lose! That means there are other cheaters! I would call them out and tell them I am cheating and that they are too. Most would say they weren t but I had a few admit they were.

What did I do? I quit playing the game when I realized it was more than 25% cheaters. I knew that I got nothing out of it. Cheaters don t get better at what they do. They cheat because they suck and can t handle the fact that there are better people in the world. Which goes back to society, because society creates these feels(sports, for example... just turn on TV and you ll see someone talking about how X is so great because he did Y... and it subconsciously makes you feel like you are not great, even though you are because your in the top 0.00000000001% of intelligence on this planet and probably galaxy).

Games are suppose to be about learning. When you cheat you don t learn. Society has forgot that and instead make fun of people that are not as good at something as someone else... but this is almost solely due to time. People good at X put in a ton of time in it. Cheaters don t get that. They first think the other person must be cheating because "How could I lose??!?! I am a genius! They must be cheating! I will cheat too! I m saved, I will go to heaven! So it s ok!".

Think about it!

If people were completely honest and cared about everyone else(because it matters), we wouldn t have: Murders, cheaters, scammers, captchas, passwords, rich/poor, iOS(ok, joking ;), etc...

It can be done but only through enlightenment. When people learn the world isn t flat, that it takes two to tango, etc then we will get beyond all this mess. Until then, we can only work on trying to make it better:

1. Don t cheat or you become like them and go to the dark side... which is only fun temporarily cause that s how it gets its teeth in you.

2. If you play any type of game with others expect that they will be cheating. If they are not cheaters, then they won t get mad. When someone accuses me of cheating I take it as a compliment because it means I am better than they are(well, that s ego but it s ok because I don t take it personally ;)

3. Playing with cheaters only makes you better. Imagine 99% of people on chess.com cheating... and you don t. You will get better because you will learn strategy. They can t beat you in the real world then. The real deal is always better than the fake synthetic crap that America and Christianity pushes down our throats.

4. Ultimately it doesn t matter. You are going on die. There is only one purpose in life and that s to transcend. Know that if you are against cheating you are already further along than cheaters. But it s not a game, help them transcend and the world and after life will be better.

Or you can move to a large deserted island like me and just allow the bad world to cheat itself to death! I d invite you to stay but only if you can prove to me that you aren t a cheater! ;)