Secret sharing system, distributed system, distributed management system, acquisition device, their processing methods, secret sharing method, a program

摘要

PROBLEM TO BE SOLVED: To generate key information according to a secure secret sharing scheme.;SOLUTION: Share information SH(α, h(α)) is generated by secret-sharing secret information independently for each subset SUB(α) and in a sharing management device PA(α, h(α)), a shared secret value DSH( α, h(α)) is generated by using common information including a shared value σ(α) that is shared for each subset SUB(α) and the share information SH(α, h(α)). In an acquisition device, a secret restoration value SUBSK(α) is generated by restoration processing for each subset SUB(α) while using a plurality of shared secret values DSH(α, h(α)) corresponding to the same subset SUB(α), and generation information SK that is key information is generated by using the secret restoration value SUBSK(α).;COPYRIGHT: (C)2013,JPO&INPIT