He received his Ph.D. degree from Electrical and Computer Engineering department at the University of Massachusetts, Amherst, in May 2002. His current research directions include Peer-to-Peer systems, overlay networks, network measurement, online social networks, and recommender systems. He is a member of IEEE and ACM and is currently serving as an associate editor for IEEE/ACM Transactions on Networking, and Elsevier Computer Networks Journal. He is the winner of the Best Paper Award of ACM/USENIX Internet Measurement Conference (IMC) 2012, the National Science Foundation Career Award in 2010, the Best Paper Award of IEEE Conference on Computer Communications (INFOCOM) in 2009, and the IEEE Communication Society Multimedia Communications Best Paper Award in 2008.