US Patent 10396984 Apparatus and system having multi-party cryptographic authentication

An electronic device includes one or more processors that perform at least one secure multiparty cryptographic process using a plurality of modules that jointly generate authentication data based on input data. Each of the modules performs that module's part of the secure multiparty cryptographic process using secure data that is not shared outside that module. The processors update the respective secure data of at least two of the modules. The respective secure data of a first module of the at least two of the modules is updated using a modification value, and the respective secure data of a second module of the at least two of the module is updated using the modification value. The updated secure data is arranged so that, for each possible value of the operation data, performance of the secure multiparty computation using the updated secure data generates the same authentication data as performance of the secure multiparty computation using the secure data prior to the step of updating. The device further includes an output interface that transmits to a terminal the generated authentication data. The authentication data is suitable for authorizing the mobile electronic device.