中文摘要：

Liu Jiafen, born in 1980. She has been working for the doctorate in Computer Science Department of University of Electronic Science and Technology of China since 2003. She received her B.S. degree from Civil Aviation University of China in 2001, and M.S. degree from University of Electronic Science and Technology of China in 2003. Her research interests cover information security, security protocols analysis and cryptography. To whom correspondence should be addressed. E-mail： ljfwhy@sohu.com