Mr. Mell is recognized for technical advances in computer-network defense methods used in government and industrial systems. His insight and creativity led to vastly improved algorithms used in the field of intrusion detection and access control. Specifically, he (a) developed an improved network scan-detection algorithm that the U.S. Army Research Laboratory has deployed in an operational network; (b) conducted a novel analysis of network anomaly-detection leading to a new understanding of intrusion detection; and (c) developed improved algorithms for scalable access control. This work has provided both practical (fielded) advances in network intrusion detection, and advances in the science of network defense.