BROADCASTING SECRETS IN COMMUNICATION-NETWORKS

One property of a broadcast channel is that a single message broadcast ed from an originator may be received simultaneously by several recipi ents in communication links. Based on the Chinese remainder theorem (C RT), we propose a new secure broadcasting scheme to distribute differe nt secrets in one single broadcasting transaction such that each of th e secrets is dedicated to different authorized recipients. On receivin g the ciphertext broadcasted by the originator, only authorized recipi ents can obtain and authenticate their dedicated secrets individually, while no secret is revealed to unauthorized recipients. In a single b roadcasting transaction, each authorized recipient cannot know who are the other intended recipients for this transaction. Furthermore, the processes for decryption and authentication of the dedicated secret ar e performed through simple arithmetic computation, i.e., modular opera tions, hence it is suitable for the applications that the recipient ha s less computing power. We also show that the proposed scheme can with stand the attack on replaying a previously intercepted broadcasting me ssage.