中文摘要：

现有的基于口令的群密钥交换协议大都借助分组密码算法和Hash函数确保协议的安全性.本文仅借助Hash函数,构造了一种高效、可证明安全的协议.该协议在随机预言模型下是语义安全的,并能对抗离线字典攻击.与相关工作比较,本文设计的协议具有更高的计算效率.

英文摘要：

Many existing password-based group key exchange protocols use the symmetric ciphers and Hash functions to maintain their security.An efficient and provably secure password-based group key exchange protocol,using only Hash function,is proposed.It is semantically secure against off-line dictionary attacks in the random oracle model and is more efficient than the related works.