Simulator integration: Vissim (Environment simulator) + NS2 (Telecom simulator) = RuBeNS Rural & UrBan e-Travelling Network Simulator Péter Laborczi Sándor Kardos Attila Török Lóránt Vajda

Main goal  Integrate environment simulator with telecommunications simulator to evaluate protocols for specific scenarios 1.Pile-up avoidance scenario (accident prevention) 2.Road traffic information scenario (traffic jam avoidance) 3.Ad hoc tempomat scenario (driving comfort)

Example  Floating Car Data: Vehicle act as moving sensors -GPS -Weather sensors -Radar  Distributed  Centralized

Emergency signalling implementation  Purpose: Test the effects of wireless emergency warning signalling  Why? If legal restrictions forbid intervention (breaking), only signalling is possible  Implemented signalling Vehicle detecting accidents broadcasts warning message Messages are forwarded up to 1000m by cars Equipped car drivers are notified when the message is received Cars with no warning device notice the problem 1.5 seconds after the supposed reception

Ad hoc traffic information sending/handling  Purpose: To avoid traffic jams without central infrastructure  Why? Reduce travel times without a single point of failure and maintainance costs  Implemented signalling Equipped cars send travel time information They receive information for all neighboring streets Based on this information they reroute when necessary

GPS module  Purpose: Realistic modelling of GPS errors  Why? Crucial to prevent bump-ins  Error sources and modelled error [m]: Error sourceGPSDGPS Satellite Clocks1.50 Orbit errors2.50 Ionosphere50.4 Troposhere Receiver noise0.3 Multipath0.6

Graph representation of road network  Purpose: To have a mathematically tractable model of the map  Why? To be able to find shortest path (Dijkstra) between locations and be able to select relevant messages  Implementation of an online ”converter” from Vissim road network format to our (Boost library based) graph format

Realworld map converter  Purpose: Convert XML format map file to VISSIM format  Why? To be able to simulate traffic in real cities  Part of Budapest (BUTE surroundings) can now be examined within RuBeNS Danube Kalvin sqare BUTE surroundings

XML based traffic matrix handling  Purpose: To have an easily usable traffic description  Why? To be able to examine different traffic conditions  Implementation is based on xmlwrapp library

Vehicular communication systems - Software Modules VISSIM Road traffic simulator VISSIM interface TCP/IP Socket NS-2 TCP/IP Socket PHY Communication Protocol Application / Group comm. interface WindowsLinux

Four Scenarios 1.Traditionalsee the DEMO No equipped vehicles 2.Centralized FCD 3.Distributed FCDsee the DEMO Ad-hoc route guidance 4.Cooperative route guidancesee the DEMO

Average Travel Time Traditional scenario Centralized FCDDistributed FCD Cooperative Route Guidance Average travel time386.5 sec164.2 sec156.8 sec114.2 sec Route travel times

Lookout  Simulation environment RUBeNS implemented to simulate: Road network & vehicle traffic Infocommunication network & data traffic  Different FCD approaches and communications simulated  More applications are under development: Ad-hoc tempomat (ACC) pile-up avoidance Intelligent flooding protocol  Study of the communication network: Load Latency Reliability