"For over 50 years the dominant model of computer security has been logical, meaning that a system is secure or insecure in the sense that a proposition is true or false. Given the reality of today's software and network environments, with their enormous complexity as systems and the diversity of user requirements and behavior, this model is hopeless. The talk will present some conceptual frameworks which may prove more promising for modeling security, and further, providing answers to compelling needs such as quantitative metrics for security."

Jonathan M. Smith is the Olga and Alberico Pompa Professor of Engineering and Applied Science at the University of Pennsylvania. He has recently returned from almost three years as a Program Manager at the Defense Advanced Research Projects Agency (DARPA), where he managed programs in areas ranging from network protocols and network security to quantum information science. Smith's current research interests range from programmable network infrastructures and cognitive radios to architectures for computer augmented immune response. He is an IEEE Fellow and serves on the President's Council of Advisors on Science and Technology (PCAST) Network and Information Technology Technical Advisory Group.