The first and best known method of implementing an electronic cash system which meets all the assumptions presented above was firstly outlined in [3] and then proposed in [4] by David Chaum. This scheme has become the reference example for implementing an electronic cash exchange, presented e.g. in [7][10][15][16]. In this solution, the banknote is composed of a signed n element sequence of pairs Pi (i ∈ 1, 2,…, n) having the following structure: