REALSecure: Random Number Encryption (RBD5411)
In this article JC Cruz will show you how to use a random number generator as the basis of a cipher system. We will also learn more about the LFSR generator, and how to make it non-linear. We will then build a basic Vernam cipher using the modified LFSR generator and REALbasic.
A great article on cryptography and ciphers.