Ad hoc routing protocols: emulation vs simulation

This paper presents an emulation platform obtained as extension of the simple ad hoc simulator (SAM) [P. Bergamo et al., Feb 2002] (where many routing protocols for ad hoc networks are implemented) and discusses the results obtained when the OLSR routing protocol is considered. Emulation can give a controlled, reproducible environment for running live code in a small, lab-environment network. Furthermore, the benefits of network emulation include the ability to expose experimental algorithms and protocols to live traffic loads, and to introduce real packet processing times. Finally, in many cases, a large number of hosts can be considered without impact on the final cost. With respect to a wireless live test, the emulator used in this paper works on hosts connected each other via wired links and the wireless channel is simulated. A direct comparison between simulation and emulation results is presented to underline the benefits of emulation.