“It simply works.”

FC1 is a symmetric key algorithm that offers an unprecedented grade of confidentiality. Based on the uniqueness of the modular multiplicative inverse of a positive integer a modulo n and on its computability in a polynomial time, this non-deterministic cipher can easily and quickly handle keys of millions or billions of bits that an attacker does not even know the length of.

The minimum recommended primary key length is 501 bits. The maximum length is instead not defined because it only depends on the limits of the system on which the algorithm is run. In our tests we went as far as keys of over one Gigabit, which means a length of over a billion bits.

Now, if by hypothesis the attacker knew the length of the key (but usualy he does not) for a brute-force attack he would have to try about  $2^{}$ different combinations!