INFORMATION GENERATING DEVICE, INFORMATION GENERATING METHOD, AND INFORMATION GENERATING PROGRAM AND STORAGE MEDIUM THEREOF

摘要

Hierarchical cryptography expressed in a general semiordered structure other than a tree structure is implemented. In information generation, random numbers à v and (à vj ) jˆˆw(v) ˆˆ Z q are generated; main information k v = à v £ i ˆˆ {1, ..., N - 1} / w(v) v i b i * + b N * is calculated; and derivation information k vj = à vj £ i ˆˆ {1, ..., N - 1} / w(v) v i b i * + b j * is calculated for each j ˆˆ w(v) . In information derivation, random numbers à u and (à uj ) jˆˆw(u) ˆˆ Z q are generated; main information k u = à u £ i ˆˆ w(v)= / w(u) u i k vi + k v is calculated; and derivation information k uj = à uj £ i ˆˆ w(v) / w(u)ui k vi + k vj is calculated for each j ˆˆ w(v).