A Novel Group Key Management Protocol Based on Secure Key Calculation Code

Abstract

This paper presents a novel group key management protocol based on secure key calculation code, which achieves the security requirements of forward security, backward security and collusion resistance. Compared with LKH (logical key hierarchy) and OFT (one-way function tree) protocol, the performance of our protocol is more efficient in crucial rekeying process when group members change dynamically. In fact, the required communication of rekeying is almost the same as that in the most efficient protocol CKC (code for key calculation), but we repair the security vulnerability found in CKC. In addition, we propose an encryption manner named “one message one key” by use of key evolution. It enables that every group member employs a distinct key when encrypting a new message, which improves the security level furthermore.