中文摘要：

由于移动互联网络的快速发展，在不安全的移动通信环境中如何构造安全的密钥协商协议是一个富有挑战性的问题．2012年高海英设计并实现了一个在标准模型下的安全的认证密钥协商协议．通过对该协议的安全性分析，发现该协议在无会话密钥托管模式下并不满足PKG前向安全性．为了弥补该协议的不足，提出了一个安全的基于身份认证密钥协商协议．该协议能够抵抗未知密钥共享和密钥泄露伪装攻击，同时具有前向安全性和已知密钥安全等安全性质．方案的安全性分析表明，新的方案比高海英的协议具有更高的安全性．

英文摘要：

With the fast development of the Mobile Internet ,How to construct secure key agreement protocol is one of the most challenging in the unsafe mobile communications environment.In 2012,Gao Haiying proposed an efficient Identity Based authenticated key agreement protocol ,which is proved to be secure in the standard model.Gao’s protocol was analysed and showed that it didn＆#39;t provide PKG-forward secrecy in key escrowless mode.To solve this problem,a secure protocol was proposed.It also provided known-key security and forward secrecy resists key-compromise impersonation and unknown key share attacks.Results show that the protocol provides PKG-forward secrecy in escrowless mode .