How Do You Make A Bet So That The Bookie Can’t Tell How Much You Have Won?

I have created a demo here of the method used, and is just a simple example that illustrates how we can multiply cipher values with RSA.

Homomorphic encryption

Too much of our data world gives away sensitive information, and we thus need to move to a world where we can process data without revealing its actual information. In this way we can process data within systems and even though someone is looking at the data processing, they cannot determine the actual values being used. This is the dream of homomorphic encryption.

Some of the proposed schemes are defined as partially homomorphic — where they can support a number of mathematical operations on encrypted values — and others as fully homomorphic. In this case, I’ll use a simple RSA method to multiply two ciphered values, and gain the result of a multiplication when we decipher them.

Multiplying cipher values with RSA

So with RSA we cipher with:

Cipher = Mᵉ mod N

and where e is the encryption key, and N is the multiplication of two prime numbers (p and q). The difficulty in this is factorizing N to get two prime numbers. To decrypt, we find the decryption key (d) and then…