Professor Larry Wittie
Computer Science, Room 1426
LW@cs.usb.edu 632-8456 / 271-5162

(1-2 students)

The student(s) will be asked to help Prof. Wittie in his simulation studies of ultra-fast computer networks, built with cryoelectronic superconducting switching elements and links. Over the last three years, over 1200 networks for 4,096 computers have been studied to a find a few capable of routing 0.5 to 7 petabytes per second (PB/s) of low latency (<20 nanosecond end-to-end) single word data packets using low-temperature superconducting (LTS) switches capable of routing two packets every 30 picoseconds. A petabyte is 1 million gigabytes. A picosecond (ps) is 1/1000^th of a nanosecond (ns), and 1 millionth of a microsecond. In a planned 7 PB/s switch running in 0.5 cubic meters of liquid helium, 80% of the 20 ns cross-network latency comes from signal flight delays, because of the finite speed of light (0.3 m/ns) and superconducted current signals (0.13 to 0.20 m/ns, and only 4 to 6 cm/switching-cycle-of-30ps).

Two previous students have combined projects to trace the distribution of randomly destined packets issued by one or a few selected nodes and to visualize 3 to 10 dimensional mesh networks in 3 dimensions (3D). The result is a tool for studying distribution of packet traffic in 5D mesh networks as wired in actual 3D space. The hope is to find optimal placement of 4,096 computer packet sources in a 7 PB/s network, so that packet traffic is uniformly distributed over all links, without congestion hot spots. Another student has started modeling a 12-stage banyan switching network, using the same simulation engine, to validate results obtained with another simulation system.

Work on this project can be done by one or two students working directly with Prof. Wittie, who codes, maintains, and heavily uses the main production version of the simulation system.