Résumé: This paper proposes an efficient secret sharing scheme to simplify the secret construction in generalized group-oriented cryptography (GOC). In our secret sharing system, a secret can be reconstructed by a predetermined group of participants through authorized access. The generation of a shadow key for each designated participant in the group can be computed directly from the access tructure, without investigating the negative access structure, so that the secret may be revealed. Moreover, the security remains at the same level as the solving of a complicated factorization problem in the RSA assumption.

Langue: Anglais