Enabling large-scale simulations: Selective abstraction approach to the study of multicast protocols

Due to the complexity and scale of the current Internet, large-scale simulation is an increasingly important tool to evaluate network protocol design. Parallel and distributed simulation is one appropriate approach to the simulation scalability problem, but it can require expensive hardware and have high overhead We investigate a complimentary solution -simulation abstraction. Just as a custom simulator includes only details necessary for the task at hand, a general simulator can support configurable levels of detail for different simulations. We demonstrate two abstraction techniques in multicast simulations and show that they each help to gain one order of magnitude in performance. Although abstraction simulations are not identical to more detailed simulations, in many cases these differences are small and result in minimal changes in the conclusions drawn from simulations.