Routing and Network Coding on Lines, Stars, and Rings

SPEAKER: Dr. Gerhard Kramer, Bell Laboratories,
Alcatel-LucentABSTRACT: Network coding allows each node in a network to combine its input information instead of simply storing, copying, and forwarding data. We present several recent results. The first is a new upper bound on network coding rates that applies to wireline, wireless, and mixed wireline/wireless networks. The bound, called a progressive d-separating edge set (or PdE) bound, involves progressively removing edges from a network graph and checking whether certain strengthened d-separation conditions are satisfied. Second, we consider line networks that are elements of larger networks. We show that under both edge and node capacity constraints the optimal code is a combination of rate-splitting, copying, routing, and "butterfly" binary linear network coding. Third, we consider star and ring networks and develop related results.This work was done jointly with Sadegh Tabatabaei and Serap A. Savari.BIO: Gerhard Kramer received the B.Sc. and M.Sc. degrees in electrical engineering from the University of Manitoba, Winnipeg, MB, Canada, in1991 and 1992, respectively, and the Dr. sc. techn. (Doktor der Technischen Wissenschaften) degree from the Swiss Federal Institute of Technology (ETH), Zurich, Switzerland, in 1998. From July 1998 to March 2000, he was with Endora Tech AG, Basel, Switzerland, as a communications engineering consultant. Since May 2000 he has been with Bell Laboratories, Alcatel-Lucent, Murray Hill, NJ, USA.HOST: Prof. Giuseppe Caire, caire@usc.edu

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

Audiences: Everyone Is Invited

Contact: Mayumi Thrasher