associated with the cryptographic protocol in which the trusted entity 2 is involved in association with the signature entity 3 and that requires one or more bilinear pairings to be calculated furthermore in the presently described example it is assumed that it is the entity 2 that delegates calculating the bilinear pairing to the calculation server 4 in a variant and where appropriate the entity 3 could equally well delegate such a calculation and be an entity in accordance with the invention in particular if it does not have sufficient computation power to carry out the calculation the invention thus applies to various delegation configurations the entity 2 delegates a bilinear pairing calculation to the calculation server 4 or the entity 3 delegates such a calculation to the calculation server 4 or indeed both of the entities 2 and 3 delegate such a calculation to the calculation server 4 in accordance with the invention in the presently described embodiment the entity 2 incorporates a silicon chip 2 a and communication means 2 b for communicating with the signature entity 3 and the calculation server 4 the silicon chip 2 a includes transistors suitable for constituting logic gates of non programmable wired logic for executing steps of a method of obtaining a bilinear pairing value in accordance with the invention these steps are described below with reference to fig2 to 4 in various implementations this wired logic defines in corresponding manner functional modules of the entity 2 that are suitable for performing the steps of the obtaining method of the invention for obtaining a bilinear pairing value and in particular a module for selecting both public and secret elements a module for generating elements r 1 r 2 t 1 and t 2 as described below a.