What security measures should I take for my gambling site?
While I don't have any inside information, I would be very surprised if the top gambling sites didn't use secure coding methods like the ones mentioned as they deal with real money and very often large sums.
I know that some online poker websites use elaborate mechanisms for bot detection such as statistics and click detection.
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Yes, as JPCosta mentioned, a big security issue for online gambling is the bots that players use to play on behalf of. These bots are written to cross other bets, use smart logic and place bets. This results in people playing / betting against bots (but assuming it is a human). This wins fair play, and if he loses more often, he will leave the site.
There are third party services that can be integrated with your application to quickly find bots. One of these is ShieldSquare
Disclaimer: I am one of the co-founders of ShieldSquare, a bot detection solution.
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