Switching the Optical Divide: Fundamental Challenges for Hybrid Electrical/Optical Datacenter Networks
FuDiCo II: S.O.S. (Survivability: Obstacles and Solutions), 2nd Bertinoro Workshop on Future Directions in Distributed Computing, 23-25 June 2004, University of Bologna Residential Center, Bertinoro (Forlì), Italy.
Hamid Hajabdolali Bazzaz*, Malveeka Tewari*, Guohui Wang**, George Porter*, T. S. Eugene Ng**, David G. Andersen, Michael Kaminsky†, Michael A. Kozuch†, Amin Vahdat*
Dept. Electrical and Computer Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
*University of California, San Diego
Recent proposals to build hybrid electrical (packet-switched) and optical (circuit switched) data center interconnects promise to reduce the cost, complexity, and energy requirements of very large data center networks. Supporting realistic traffic patterns, however, exposes a number of unexpected and difficult challenges to actually deploying these systems "in the wild." In this paper, we explore several of these challenges, uncovered during a year of experience using hybrid interconnects. We discuss both the problems that must be addressed to make these interconnects truly useful, and the implications of these challenges on what solutions are likely to be ultimately feasible.
FULL PAPER: pdf