18th Workshop on Parallel and Distributed Simulation, 2004. PADS 2004. (2004)
May 16, 2004 to May 19, 2004
Jason Liu , University of Illinois at Urbana-Champaign
Yougu Yuan , University of Illinois at Urbana-Champaign
David M. Nicol , University of Illinois at Urbana-Champaign
Robert S. Gray , Dartmouth College
Calvin C. Newport , Dartmouth College
David Kotz , Dartmouth College
Luiz Felipe Perrone , Bucknell University,
Computer simulation is the most common approach to studying wireless ad-hoc routing algorithms. The results, however, are only as good as the models the simulation uses. One should not underestimate the importance of validation, as inaccurate models can lead to wrong conclusions. In this paper, we use direct-execution simulation to validate radio models used by ad-hoc routing protocols, against real-world experiments. This paper documents a common testbed that supports direct execution of a set of ad-hoc routing protocol implementations in a wireless network simulator. The testbed reads traces generated from real experiments, and uses them to drive direct-execution implementations of the routing protocols. Doing so we reproduce the same network conditions as in real experiments. By comparing routing behavior measured in real experiments with behavior computed by the simulation, we are able to validate the models of radio behavior upon which protocol behavior depends. We conclude that it is possible to have fairly accurate results using a simple radio model, but the routing behavior is quite sensitive to one of this model?s parameters. The implication is that one should i) use a more complex radio model that explicitly models point-to-point path loss, or ii) use measurements from an environment typical of the one of interest, or iii) study behavior over a range of environments to identify sensitivities.
C. C. Newport et al., "Simulation Validation Using Direct Execution of Wireless Ad-Hoc Routing Protocols," 18th Workshop on Parallel and Distributed Simulation, 2004. PADS 2004.(PADS), Kufstein, Austria, 2004, pp. 7-16.