Eecient and Accurate Ethernet Simulation

The Internet is increasingly being called upon to provide di erent levels of service to di erent applications and users. A practical problem in doing so is that although Ethernet is one of the hops for nearly all communication in the Internet, it does not provide any QoS guarantees. A natural question, therefore, is the effect of o ered load on Ethernet throughput and delay. In this paper, we present several techniques for accurately and e ciently modeling the behavior of a heavily loaded Ethernet link. We propose an e cient distributed simulation model, called Fast Ethernet Simulation, that empirically models an Ethernet link to quickly and accurately simulate it. By eliminating the implementation of CSMA/CD protocol, our approach reduces computational complexity drastically while still maintaining desirable accuracy. Performance results show that our techniques not only add very little overhead (less than 5% in our tests) to the basic cost of simulating an Ethernet link, but also closely match real-world measurements. We also present e cient techniques for compressing cumulative distributions using hyperbolic curves and for monitoring the load on a heavily loaded link. Finally, we show applications to illustrate the potential usage of the Fast Ethernet Simulation.