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MD5 integrity control

Many online casino players often think that they are simply being lied to on the casino site. Most of the time, this happens when they lose all their money. However, many visitors do not even realise that there is such a thing as controlling the integrity of the casino in the industry of the online casino games. So what is it?

Integrity control is just a regular program that works according to a certain encryption algorithm, and it has one main task; in the roulette, for example, it ensures that the ball lands on each number with the same probability, which means that the casino cannot set the wheel to show a specific number all of a sudden. There are many programs like this, and one of them is MD5.

The MD5 is a hashing program. What is that? Hashing is an action that uses a hash function. But the hash function is a function that converts any data into a sequence of bits of a certain length, that is, into the same data but compressed to the desired size. So integrity control is a 128-bit hash value.

The MD5 algorithm was developed by Ronald Linn Rivest, a professor at the Massachusetts Institute of Technology. This algorithm creates traces of messages of different lengths. Each hash function of the MD5 algorithm is a 32-bit sequence represented in the hexadecimal system, which means that it is a sequence of numbers from 0 to 9 and Latin letters from A to F. From the definition of what the hash function is and the main idea of MD5, we can draw the conclusion that the final result will always be a 32-bit sequence, regardless of what the original size and the input data were.

So how does it control the integrity factor of the gambling establishments?

It’s simple. The fact is that the hash function is irreversible, which means that if the data has already been hashed, it is impossible to get it back in its original form. Therefore, it is impossible to do any modifications to it, and therefore it is impossible to crack it and find out the encrypted sequence.

What this means is that even if someone wants to change the sequence (for example, to cheat players in an online casino which uses the MD5), and even if they manage to get to it, the sequence will be in bit format, and they simply will not be able to decrypt and replace it, since every hash function is unique. This can easily be proven. MD5 uses a 128-bit algorithm. Each bit can be represented by sixteen different characters. Just imagine how many possible combinations you can get at the final result.

This is how the casino integrity control using the MD5 algorithm works: before the cards are distributed (the series of spins in roulette or a series of spins on slots starts, etc.), a random sequence of results is created and then it is encrypted by the MD5 algorithm together with some additional service information.

For example: 21-29-2-31-14-22-15-33-0-19-25-10-28-13-11-q5w225x6b. These are the numbers that the ball will land on in roulette, and at the end, there’s a special key (which is constantly changing) that makes it impossible to access and decrypt the hash.

To control the integrity of the casino, the player will receive a line encrypted in MD5 – 50c1554319b7e027593d5cd16dc51e07. The players themselves cannot see the line.

At the end of the game (at the end of the series), the player will be able to see the string, which was encrypted.

To control the integrity of the casino, it is necessary to encrypt the string with the results on any MD5 encryption service and compare it with what was given to the player before the game started.

If the results match, then there is no doubt that the integrity control works and the casino is honest.

What is the MD5 casino honesty control mechanism?


Almost all modern online casinos vehemently try to prove their honesty, and they expose the MD5 integrity control mechanism as a confirmation of that.

Description of the MD5 integrity control MD5 FairPlay fairness control

In order to provide players with the confidence that the results of the game in the casino are completely random and depend on nothing else but their decisions and actions taken during the game, we give them the ability to control the integrity of the online casino.

The MD5 FairPlay integrity control system is based on advanced cryptographic technologies and algorithms, and the functioning model of this system is based on the following fundamental conditions:

Before starting the game, the player has to prepare the game data independently (the casino game results) for one or more subsequent games (series), which record the game data – random numbers in roulette, random arrangement of cards in a deck, etc. in future games. This data is recorded as a text. 

The game data generated as plain text is digitally signed (hashed). The digital signature is generated using the publicly available MD5 cryptographic algorithm (RSA Data Security, Inc. MD5 Message-Digest Algorithm). After the data was digitally signed, making any changes to it during the game in the online casino becomes impossible. Game data becomes available to the player only after the games recorded in it have finished. 

The digital signature for game data is available before the start of the game, during and at the end of the game. This means that the player can control the invariance of the game data during their active game actions (choosing bets, cards, the place in the deck from which the game will start, etc.).

The casino does not have the ability to manipulate game data that is digitally signed and which is initially known to the player. This means that the casino cannot rearrange the cards in the deck, change one number for another in the sequence of falling numbers etc., since the game data will change as a result of such actions, and the changed game data will have a different digital signature. Such changes will be obvious and completely under the control of the player. This is how the casino’s integrity can be confirmed.

At the end of a game or a series of games, the casino player can check:

  1. a) that he had exactly the numbers, cards, etc., that were recorded in the casino game data. A simple comparison of the player’s results in a game that has already taken place with what they should have gotten will show if it was correct. This information becomes available immediately after the end of the game in the online casino and is strictly ordered.
  1. b) that the pre-prepared data was not altered during the game. This can be checked by comparing the digital signature, which was available to the player before the start of the game, and the digital verification signature. A verification signature is a new reproduction of the MD5 digital signature of the game data, which the players request independently. You can also get a verification signature by using independent sites, programs, etc. because the MD5 algorithm is publicly available. If both digital signatures match, that means that the game data did not change from the moment it was created until the end of the game.

How the MD5 mechanism works in an online casino


Before a casino game starts, a random sequence is generated using a random number generator, which is encrypted using the MD5 mechanism.

The player can receive this sequence in encrypted form and, immediately after the game, compare it with the sequence (digital signature) in the casino and see what was encrypted (a sequence of random numbers).

It is possible to decipher the sequence, but it will take about 10,000 years.

Gemma Heathcote
Gemma Heathcote.

Gemma Heathcote – Editor @ Superlenny

Gemma is the Editor of SuperLenny.com, where her main responsibility outside of editing and writing content is overseeing everything published online. She’s also ensures the day to day operations of SuperLenny are kept running smoothly, including keeping Josh and Matt in check!