Friedman is Principal Investigator on NSF Grant to Study Complex Dynamics in the Internet

Like other systems that evolve over time - galaxies, climate, economies, even brains - the Internet can be analyzed as a dynamical system. Researchers in a wide variety of disciplines investigate the evolution, efficiency,and stability of such systems. Large systems such as the Internet pose particular problems, since the complexity at a granular level can be overwhelming while ignoring fine details to assure tractability risks neglecting features needed to resolve practical engineering issues. The National Science Foundation (NSF) has awarded ORIE Professor Eric Friedman and two Cornell colleagues a $1.5 million grant to apply novel analytical and computational techniques to the study of the Internet. With co-Principal Investigators Professor Steven Strogatz and Assistant Professor Ao Kevin Tang, Friedman will apply novel techniques combining computational and analytical approaches, using such methods as "equation-free modeling from chemical engineering and numerical renormalization from statistical physics" to achieve a happy medium between focus on details and tractability. The investigators will explore three problems: understanding the overall efficiency and stability of the Internet, developing methods to improve the functioning of large arrays of small sensors that can be used to monitor environmental changes, and developing incentives for individual users of large cooperative computing systems to behave in ways that benefit the whole. The team anticipates spin-offs applicable to other problems, such as routing on the internet, synchronization in neural networks, and stability in global financial networks. The grant proposal characterizes the approach as "radically interdisciplinary," in drawing on fields such as dynamical systems theory, mathematical physics and theoretical biology. The team itself is interdisciplinary in nature, with Friedman from ORIE, Strogatz from Theoretical and Applied Mechanics (TAM), and Tang from Electrical and Computer Engineering (ECE). 

As a Ph.D. candidate at Caltech, Tang already developed ties to operations research, having won, in 2006, the prestigious George B. Dantzig Dissertation Award from INFORMS, the Institute for Operations Research and the Management Sciences, for his paper on control of congestion in heterogeneous networks. The prospect of collaboration with other Cornell faculty to make similar contributions is what drew Tang here. In addition to colleagues in ECE, at Cornell "there's a strong computer science department and a strong operations research department, so I can reach out to these strong potential collaborators easily," said Tang. 

Friedman, who joined ORIE in 2001, has a multidisciplinary background. His undergraduate degree is in physics (from Princeton) and Masters and PhD degrees in Operations Research (from Berkeley). Prior to coming to Cornell he was at the Duke University Fuqua School of Business and the Rutgers University Department of Economics. His research interest is at the intersection of game theory, computer science, and operations research.  

Strogatz recently completed development of a DVD-based course on chaos theory (which pertains to dynamical systems) for the Teaching Company. With Duncan Watts, he is the co-author of one of the most highly cited papers on networks and the sixth most highly cited paper in physics in the past decade.  

The four year grant is one of the first awarded through the NSF's new Cyber-Enabled Discovery and Innovation (CDI) program, which received 1671 submissions in its first year and awarded a total of $52 million to only 2% of the proposers. The program is a five-year multidisciplinary initiative to "create revolutionary science and engineering research outcomes made possible by innovations and advances in computational thinking," according to the NSF. One of the three thematic areas emphasized by the CDI program in its solicitation for proposals is "Understanding Complexity in Natural, Built and Social Systems: deriving fundamental insights on systems comprising multiple interacting elements," which certainly describes the Internet as a system.   

The three collaborators are active in dissemination of knowledge and interaction with industry. In addition to developing a course for a broad audience Strogatz has written books for the general reader, including the soon-to-be released The Calculus of Friendship: What a Teacher and a Student Learned about Life while Corresponding about Math. Tang has been collaborating with Facebook, and Friedman has been working with eBay and IDT.

Friedman said "I'm looking forward to working with Kevin and Steve. This is a great opportunity to try some totally new approaches to important problems. Our main goal is to apply deep results from dynamical systems in a computational approach that will be able to solve significant problems that are currently intractable."