1. Realistic Mobility Models for Vehicular Ad hoc Network (VANET) Simulations
Kun-chan Lan and Chien-Ming Chou
National Cheng Kung University
Speaker：潘逸峻
Adviser：許子衡 老師

2. Outline Introduction Effects of details of mobility models
Important simulation parameters
Simulation tools (MOVE)
Experimental Background
Effects of details of mobility models
Existence of traffic lights
Driver route choice
Overtaking behavior
Conclusion and Future work

3. Introduction
VANET
Enable quick and cost-efficient distribution of data for the passengers.
Simulation tools
Test and evaluate network protocols.
EX：ns-2 , OPNET and Qualnet.

4. Important simulation parameters
Node mobility model
consist a realistic topological map:
different densities of roads and different categories of streets with various speed limits.
Deceleration and acceleration model.
Turning model : decide a turning direction at the intersection.

5. Mobility model generator for Vehicular networks(MOVE)
Rapidly generate realistic mobility models for VANET simulations.
Built on top of an open source micro-traffic simulator SUMO.

6. Map Editor
Create the road topology.
Three ways to create the road map
1. Created by the user.
2. Generated automatically.
3. Imported from existing real world maps.

7. Vehicle Movement Editor
Specify the trips of vehicles and the route .
Three methods to define the vehicle movements
1. Created by the user.
2. Generated automatically.
3. Specified based on a bus time table to
simulate the movements of public transport.

8. Experimental Background
Nodes location, density, and direction etc.
affect VANET performance directly.
Mobility models generated : MOVE
Road topology generated : TIGER database
Node : MAC operating at 2Mbps
Transmission range : 250m

9. Effects of details of mobility models
Three case studies
Traffic lights.
Driver route choice.
Car overtaking.
Number of nodes : 300.
Simulation time lasts : 1000 seconds.
Roads created : two lanes.

10. Existence of traffic lights
Clustering effect
a traffic light have a higher node density.
improve the network connectivity
higher chance for packet collision
The distance between two traffic lights

11. A larger number of neighboring nodes typically suggests a better network connectivity

12. Packet delivery ratio decrease when there are
more traffic sources.

13. Two adjacent clusters which significant
degrades the network performance.

14. traffic light cycle can also have a significant
impact on the network performance.

15. Driver route choice Different choices of route directions can
significantly change the simulation results.

16. Overtaking behavior
when overtaking behavior is not allowed, it usually results in a chain-like topology and a shorter and uniform inter-vehicle distance

17. Conclusion and Future work
In this paper, we show that the details of a mobility model can have a significant impact on the simulation results
Build an interface to tightly integrate SUMO and ns-2 , vehicle state information (such as location, speed, direction, etc.) can be fed into ns-2 in real time.