Robert Walls is a Postdoctoral Scholar in the Department of Computer Science and Electrical Engineering at The Pennsylvania State University. His research interests include systems security and digital forensics. He is currently studying the abuse of Internet infrastructure, including advertising networks and the Domain Name System (DNS). Previously, he worked with law enforcement to develop novel forensic techniques for investigating crimes. He received his Ph.D. in Computer Science from the University of Massachusetts Amherst in 2014. He is also a recipient of the Yahoo! Key Scientific Challenges Award.