Low Bandwidth Self-Healing Key Distribution for Broadcast Encryption

We introduce a new self-healing key distribution scheme with revocation capability. The main improvement that our proposed construction achieves over previously suggested self-healing key distribution schemes is that our self-healing technique reduces communication overhead from O(tj) to O(t+j) without any additional increment in the storage cost as compared to the earlier approaches, where j is the current session number and t is the maximum number of compromised group members that may collude. We provide rigorous treatment of security of our scheme in an appropriate security framework and show that it is unconditionally secure with forward and backward secrecy.