ID-Based Threshold Unsigncryption Scheme from Pairings

摘要

An identity-based threshold unsigncryption scheme is proposed, which is the integration of the signcryption scheme, the (t,n) threshold scheme and zero knowledge proof for the equality of two discrete logarithms based on the bilinear map. In this scheme, a signcrypted message is decrypted only when more than t members join an unsigncryption protocol and the signature can be verified by any third party. A formal proof of security of this scheme is provided in the random oracle model, assuming the Decisional Bilinear Diffie-Hellman problem is computationally hard.