An ID-Based Signcryption Scheme with Compartmented Secret Sharing for Unsigncryption

In Li, Xin, and Hu describe an ID-based signcryption scheme that uses a bi-linear map to accomplish (t; n) shared un-signcryption with the help of Shamir's secret sharing scheme. Here the authors describe a way to extend Li et. al.'s construction into a compartmented scheme. In this paper, the ID-based signcryption scheme of Li, Xin, and Hu is extended to a compartmented scheme. If an organization is partitioned into different compartments, this scheme allows any member of a specific compartment to participate in the un-signcryption; moreover, each member of a compartment has information unique to that individual. This construction is the first (to the authors' knowledge) to combine identity-based encryption, Shamir's threshold scheme, and signcryption into an implementable compartmented sharing scheme.