Section: New Results

Large scale simulation interfacing

Participants : Ahmed Soua, Jean-Marc Lasgouttes, Oyunchimeg Shagdar.

In order to efficiently design and validate a cooperative intelligent transportation system, a complete simulation environment handling both mobility and communication is required. We are interested here in a so-called system-level view, focusing on simulating all the components of the system (vehicle, infrastructure, management center, etc.) and its realities (roads, traffic conditions, risk of accidents, etc.). The objective is to validate the reference scenarios that take place on a geographic area where a large number of vehicles exchange messages using 802.11p protocol. This simulation tool is be done by coupling the SUMO microscopic simulator and the ns-3 network simulator thanks to the simulation platform iTETRIS.

We have focused in this part of the project on how to reduce the execution time of large scale simulations. To this end, we designed a new simulation technique called Restricted Simulation Zone which consists on defining a set of vehicles responsible of sending the message and an area of interest around them in which the vehicles receive the packets. In fact, the messages emitted by the vehicles located outside the interference zone are not useful for the simulation of the ego-vehicle, and therefore limiting the transmission area to a useful one reduces obviously the number of nodes involved in the transmission operation and thus reduces the processing time of messages. To corroborate the efficiency of our proposal, we compare it with an already existing simulation tool called COLOMBO. The simulation results have shown that our technique outperforms COLOMBO in terms of simulation execution time in the case of large scale simulations (when the number of vehicles exceeds 2400 nodes).