Flux Research Group / School of Computing

Flexlab: A Realistic, Controlled, and Friendly Environment for Evaluating Networked Systems

Jonathon Duerig, Robert Ricci, Junxing Zhang, Daniel Gebhardt, Sneha Kumar Kasera, and Jay Lepreau

Proceedings of the Fifth Workshop on Hot Topics in Networking (HotNets) 2006.

Networking, Testbeds


Research prototypes of networked systems are often evaluated on overlay testbeds and emulation testbeds. Most of the strengths and weaknesses of these two types of testbeds are complementary. We outline the motivation, design, implementation, and sample results of an environment that seeks to provides the best of each type. Flexlab couples an emulation testbed with arbitrary network models. We also present a novel modeling technique tuned for this environment, application-centric Internet modeling. The key idea is to monitor the application’s offered network load within the emulation testbed, replicate that load on the overlay testbed, measure the path’s characteristics through analysis of the traffic, and use those to shape the emulated network.