Simpler methods for generating better Boolean functions with good cryptographic properties

We present two heuristic optimisation methods for generating N -variable boolean functions which exhibit particular cryptographic properties. Each method targets one or more properties and consistently produces a large number of N -variable boolean functions with those properties. The first method presented is shown to outperform any other heuristic technique previously reported, in terms of generating highly nonlinear, low autocorrelation balanced boolean functions. The second method discussed in this paper again outperforms any other existing heuristic technique used to generate resilient functions with high nonlinearity and algebraic degree maximising Siegenthaler’s inequality.