Adaptive Chosen Ciphertext Secure Threshold Key Escrow Scheme from Pairing

This paper proposes a threshold key escrow scheme from pairing. It tolerates the passive adversary to access any internal data of corrupted key escrow agents and the active adversary that can make corrupted servers to deviate from the protocol. The scheme is secure against threshold adaptive chosen-ciphertext attack. The formal proof of security is presented in the random oracle model, assuming the decision Bilinear Diffie-Hellman problem is computationally hard.