针对动态对等通信中的组密钥协商协议进行了分析和研究,指出王志伟等人提出的基于树结构和门限思想的组密钥协商协议(TTS)存在密钥控制和不等献性等缺陷,进而给出了一个改进的方案(I-TTS)。安全性分析表明,I-TTS协议不仅克服了TTS协议中的前向安全性和密钥控制缺陷,还满足等献性。
This work investigates the group key agreement protocols,and points out that Wang et al's key agreement protocol (Tree and Threshold Scheme,TST) is not only non-contributory,but also vulnerable to key control i.e.the sponsor of the key agreement can predetermine the group key.To over come the security flaws,this paper presents an improve scheme (I-TTS).Security analysis indicate that I-TTS scheme is contributory,and no one can predetermine the negotiated group key.Further more,the I-TTS scheme is perfect forward secrecy.