pfs: Parallelized, flow-based network simulation

Simulation is a compelling option for evaluating Internet protocols, configurations and behaviors. While current simulation tools have been used effectively to consider questions in small-scale networks, they are incapable of evaluating large scale phenomena such as routing configurations, DDoS attacks and data center deployments. In this paper, we describe pfs, a parallelized version of the fs flow-level simulator [1] that offers the opportunity to conduct very large-scale simulations of networks. Our approach to parallelization is based on decomposing simulation configurations both spatially and temporally into independent chunks that can be run simultaneously on massively scalable, parallel processing infrastructures. We demonstrate the capabilities of pfs through a series of experiments that highlight both the speedup that can be achieved as well as the costs that are incurred in terms of the accuracy of the simulation results.