ns+SDL -: The network simulator for SDL systems

Today, simulators for the performance evaluation of networked systems are seldom integrated with tool environments used for system development and maintenance. This requires the system developer to establish and maintain separate code bases for simulation and production purposes, a tedious and error-prone task. In this paper, we present ns+SDL, an extension of the network simulator ns-2 to combine SDL design specifications with ns-2 network models. ns+SDL enables the developer to use SDL design specifications as a common base for the generation of simulation and production code. Furthermore, the same SDL-to-C code generator is used to generate this code. Both measures increase confidence that the results of the performance evaluation hold for the networked system in operation. Another important aspect is the composition of SDL systems and existing ns-2 simulation components, in particular, components implementing detailed timed models of existing communication technologies. We illustrate the application of ns+SDL by a simulation of DSDV, the Destination-Sequenced Distance-Vector routing protocol, over WLAN.