DNEmu: Design and Implementation of Distributed Network Emulation for Smooth Experimentation Control

Conducting a realistic network experiment involving globally distributed physical nodes under heterogeneous environment introduces a requirement of experimentation control between the real world network and emulated/simulated networks. However, there is a gap between them to deploy network experiments. In this paper, we propose the Distributed Network Emulator (DNEmu) to fill the gap for the requirements of a planetary-scale network experiment. DNEmu addresses the issue of real-time execution with message synchronization through distributed processes, and enables us to evaluate protocols with actual background traffic using a fully controlled distributed environment. Through evaluation with micro-benchmarks, we find that our DNEmu prototype implementation is similar in terms of packet delivery delay and throughput to the existing non-virtualized environment. We also present a use-case of our proposed architecture for a large distributed virtual machine service in a simple control scenario involving actual background traffic on the global Internet. DNEmu will contribute to research in protocol evaluation and operation in a huge network experiment without interfering with the existing infrastructure.