Abstract:

Tô et al. presented a bilinear-map-based traitor tracing scheme with revocation, but it is a symmetric scheme because it does not provide non-repudiation. An improved Tô scheme was proposed using oblivious polynomial evaluation (OPE) protocol and service parameters. Under the precondition of general sameness capabilities of both Tô’s and improved Tô’s scheme, the new scheme adds some advantages such as providing multi-service capability, user’s non-repudiation and data provider’s no-framing innocent users. Furthermore, it is also proved to be semantically secure under the decisional bilinear Diffie-Hellman problem (DBDH) assumption.

Key words: bilinear map, traitor tracing, multi-service, asymmetry