Doctor, researcher, doctoral supervisor. He once worked in Tsinghua University Institute of Network Science and Cyberspace, director of Network and Information Security Laboratory, visiting scholar at University of California, Berkeley, and certified expert of International Information System Security (CISSP). Engaged in teaching, scientific research and operation management related to computer network security for a long time. He has undertaken two courses related to network security for undergraduates and postgraduates in Tsinghua University Computer Department, and undertaken many scientific research projects such as National 973, 863 and Natural Science Foundation, and was the leader of CCERT (Computer Network Emergency Team for Education and Scientific Research) in China. The research results have been published in many top academic conferences or journals related to network and security, which have had an important impact on the international industry.