Method for tracing traitor receivers in a broadcast encryption system

The invention relates to a method for tracking receiver rebel a cryptographic broadcasting system. The method comprises represents one fake key coding system of subsets of receiver. The subsets with a subset of covering system promotes from a tree, the rebel receiver contacted with one or more end keys, the keys are obtained by a pirating receiver of latent simulation. With pirating of the receiver counterfeits machine, wherein a a a subset device, the rebel receiver state is determined that or pirate to a receiver counterfeited machine a it with key end a data.