CrowdLab: An architecture for volunteer mobile testbeds

Researchers investigating mobile and wireless systems can run experiments on many testbeds, but no existing option supports experimentation “in the wild“ without sacrificing features such as access to low-level wireless state and efficient scheduling of co-local guests. To fill this void, we present a new architecture for mobile testbeds called CrowdLab. CrowdLab allows researchers to run guest virtual machines on volunteer mobile nodes and ensures efficient use of testbed resources through a new dual-mode networking abstraction and a weakly-consistent, replicated state store called a site directory. We have implemented two CrowdLab prototypes, one for x86 laptops and one for ARM-based Nokia N810 Internet Tablets, and evaluated them using power measurements, micro-benchmarks, and trace-driven emulation. Our evaluation demonstrates that handheld users can contribute 2.5 hours per day to CrowdLab and still have over 12.5 hours of idle time remaining. In addition, emulated mobility-trace replays show that CrowdLab's fault-tolerance mechanisms allow experiments to run uninterrupted, even in the face of high churn rates.