1. A method for implementing a system for authentication of an article based upon a signature generated from a set comprising groups of data points collected when a plurality of regions of an intrinsic surface structure of an article are sequentially subjected to coherent light and the light scattered by the intrinsic surface structure is collected, the method comprising, for a given system implementation: determining a set of parameters which influence the performance of the system; determining a definition of system performance which can be affected by the set of parameters; producing an initial population of parameter value sets, each parameter set including a value for each parameter to be used in achieving a desired system performance; determining for each parameter value set a fitness value in terms of the system performance definition; identifying mating pairs of the population in accordance with the determined fitnesses; producing a new population by crossing the mating pairs; repeating the determining of a fitness value for each parameter value set, the identifying of mating pairs and producing a new population until an end criterion is satisfied; and configuring the system in accordance with a selected one of the parameter sets from the final population; wherein the system comprises at least one record scanner operable to make a record signature for a known article, a database operable to store a record signature for a known article and a test scanner operable to make a signature for an article under test for comparison to one or more record signatures in the database.