Stanford Networking Seminar

2:30PM, Monday November 8, 2010
Gates 104

Exact Temporal Characterization of 10 Gbps Optical Wide-Area Network

Daniel Freedman
Cornell University

About the talk:
We design and implement a novel class of highly precise network instrumentation and apply this tool to perform the first exact packet-timing measurements of a wide-area network, capturing 10 Gigabit Ethernet packets in flight on optical fiber. In doing so, we improve timing precision by two to six orders of magnitude over existing techniques. Our observations contest some common assumptions about behavior of wide-area networks and the relationship between their input and output traffic flows. Further, we identify and characterize emergent packet chains as a mechanism to explain previously observed anomalous packet loss on receiver endpoints of such networks.

About the speaker:
Daniel A. Freedman is a Post-Doctoral Research Associate in the Computer Science Department at Cornell University, where he works with Ken Birman on distributed systems and networking. Prior, he received his M.S. and Ph.D. in theoretical physics, also from Cornell, and his S.B. in physics from MIT. His earlier work in condensed-matter physics involved computational studies, both empirical and ab initio, of the growth of and defects in crystalline oxides. Reflecting his academic upbringing, Freedman's research agenda is interdisciplinary in nature, drawing upon approaches from physics to address problems in computer science. His experiments push the state-of-the-art in precision and reproducibility of network measurements. Freedman has also worked on projects with a more traditional distributed-systems focus: adaptive wide-area multicast overlays and edge mashups that integrate hosted content with peer-to-peer protocols.