An efficient and robust conference key distribution protocol

A computationally secure and robust conference key distribution scheme is presented, which requires only the authenticated and encrypted point-to-point channels between each server and each user. By using it, every honest user of a conference can get a common key after running of the protocol, even if some minority of the servers malfunction or misbehave. Analysis shows that a passive adversary gets zero knowledge about the conference key, and the active adversary cannot impersonate successfully. Because this scheme is noninteractive, both operation and communication overhead are reduced, this make it very efficient.