A method of processing information to be confidentially transmitted from a first module to a second module provides that a first scalar multiplication may be carried out in order to obtain a first result [r]P. This first scalar multiplication comprises a plurality of generation steps of ordered factors from which a plurality of first partial sums are required to be built. The method also comprises the carrying out of a second scalar multiplication in order to obtain a second result. This second multiplication provides that a plurality of second partial sums may be built. A piece of encrypted information is obtained by processing the information based on the results of the scalar multiplications. The second partial sums of the second scalar multiplication use the same ordered factors obtained by the generation step of the first scalar multiplication.