In traditional online gambling, players must rely solely on the operator’s integrity, often based on the results generated by an opaque random number generator, known as RNG, that runs on the casino's servers. Without any insight into this 'black box,' players can only trust the operator's reputation or a certificate from an external testing agency.

Enter the concept of provably fair gaming, a method that lets players independently verify game outcomes. In the realm of web3 casinos, this technology locks in a game result before you place your bet, allowing you to confirm its fairness post-game, all through cryptographic methods rather than mere promises. This article outlines how the mechanism works and guides you through verifying results on your own.

Shifting from Trusting to Verifying

The crux of provably fair systems lies in transparency. Unlike traditional casinos, where game outcomes are generated within inaccessible server-side software, provably fair systems bring the proof into the open. Once a result is determined before a player's wager, they can check its honesty after the round ends. Here, it's the mathematical processes that provide reassurance, shifting the focus from brand trust to inherent verification.

The Triple Components Behind Each Game Outcome

Every fair outcome is derived from three key components, with no single entity holding them all:

  • Server seed: A random string created and published as a SHA-256 hash by the casino before placing a bet, ensuring its commitment remains hidden until checked.
  • Client seed: This string can either be defined by you or generated by your browser, which the casino cannot foresee when securing the server seed.
  • Nonce: A sequential counter that increases with each bet using the same seed pair, ensuring that even identical seeds lead to unique game outcomes.

These values feed into an HMAC-SHA256 function to yield the final outcome. Since the server seed is established beforehand and kept under wraps, the casino can't manipulate the result, and players cannot tamper with it before the game concludes.

Steps to Self-Verify Game Outcomes

The process of verification is straightforward and requires no programming skills, utilizing web-based tools. Here’s how to confirm a result step by step:

  • Before you place a wager, access the fairness panel of the game and save the hashed server seed, which will serve as your reference.
  • Input your own client seed in the same panel, ensuring the casino cannot pre-calculate outcomes.
  • Make your bet and take note of the nonce associated with the specific result you intend to verify.
  • Reveal the server seed by rotating the seed pair, exposing the original server seed in plain text and ending that session.
  • Use an independent tool to hash the revealed seed with SHA-256, and confirm it aligns with the commitment you documented.
  • Apply HMAC-SHA256 to the server seed, client seed, and nonce, then utilize the game’s published formula to verify the outcome matches what you observed.

Throughout this process, one critical recommendation is to use a verification tool separate from the casino, as running checks through the operator's tool introduces a risk of misplaced trust.

It’s important to note that not all games in web3 casinos may have provably fair systems in place. Players should ensure they are participating in games with this transparent verification method.