Dr. Walls' interests lie at the intersection of security and digital forensics. In part, he seeks to analyze and secure the large-scale, complex, inter-connected systems underpinning critical internet services. His past efforts have focused on multiple aspects of this problem, including the development of novel data collection methodologies, the analysis of partially structured data, and the transition of research results into practical tools and techniques. Before joining WPI, Dr. Walls worked as a postdoctoral scholar at Penn State University. While there, his research focused on developing a science of systems security. Previously, he attended the College of Information and Computer Sciences at the University of Massachusetts. In 2011, he received the Yahoo Key Scientific Challenges Award for his work in Security & Privacy.