Xing Li is a Professor in the Electronic Engineering Department at Tsinghua University, Beijing, China. He received his B. S. degree in radio electronics from Tsinghua University, Beijing in 1982, and his M.S. and Ph. D. degrees in electrical engineering from Drexel University, USA in 1985 and 1989, respectively. His research activities and interests include computing networks, multimedia communication and statistical signal processing. He is deputy director of China Education and Research Network (CERNET) Center and current Chair of Internet Sub Chapter of Computer Society of China. He was a member of IAB (Internet Architecture Board), co-chair of CCIRN (Coordinating Committee for Intercontinental Research Networking), Chair of APNG (Asia Pacific Network Group) and a member of APNIC Executive Council. He is co-author of 11 IETF RFCs, including the IPv4/IPv6 transition specifications (RFC4925, RFC6052, RFC6145, RFC7599, etc).