Dr. Dietrich researches computer and network security, anonymity, cryptographic protocols, and cryptography. His previous work has included a formal analysis of the secure sockets layer protocol (SSL), intrusion detection, analysis of distributed denial-of-service tools, and the security of IP communications in space. His publications include the book Internet Denial of Service: Attack and Defense Mechanisms (Prentice Hall, 2004), as well as recent articles on botnets.

His involvement with the Center for the Advancement of Secure Systems and Information Assurance (CASSIA) has been integral in Stevens Institute of Technology attaining designation as a National Center of Academic Excellence in Information Assurance Research.

He formerly served as Senior Member of the Technical Staff at CERT Research at Carnegie Mellon University and also held an appointment at the Carnegie Mellon University CyLab, a university-wide cybersecurity research and education initiative.

As one of the pioneers in computer and network security, Dr. Dietrich observed and analyzed the first distributed denial-of-service attacks against the University of Minnesota while working as a senior security architect at the NASA Goddard Space Flight Center.