1. Adaptive Routing Protocol for VANETs in City Environments using Real-Time Traffic Information 指導教授：許子衡 教授 報告學生：董藝興 學生 作者： Arzil, S.A. ; Aghdam,.H. ; Jamali, M.A.J. ; 出處： Information Networking and Automation (ICINA), 2010 International Conference on

2. Introduction The inter-vehicle communication (lVC) is ad hoc and vehicle-to-roadside communication (VRC) is through access points (roadside units). Both FleetNet and CarT ALK used multi-hop communication techniques, but while FleetNet was supported by a partial fixed infrastructure, CarT ALK used no existing infrastructure.

3. Introduction Therefore data dissemination in these projects does not perform well, due to the dynamic nature of mobile nodes in VANETs and lack of continuous end-to-end connectivity. In other words, continuous end-to-end connectivity is sporadic.

4. Introduction In such networks where end-to-end connectivity might not exist, the store-carry and forward (SCF) paradigm can be employed.

5. ARBR Protocol Assumptions – We assume that every vehicle knows its geographical position and direction through global positioning system (GPS). – Vehicles periodically send beacons reporting their positions to their neighbors. – We also assume that vehicles are equipped with digital maps to determine which road segment or intersection they are in.

6. ARBR Protocol Overview The ARBR protocol uses two mechanisms to increase delivery ratio and lower delay of delivered packets. These mechanisms consist of the following: – Discovery of high quality routing path between route-requesting vehicle and base station node and data packet forwarding along the discovered path.

7. ARBR Protocol Overview Path maintenance by updating routing information of route reply packet in intermediate nodes.

8. ARBR Protocol Overview

11. Simulation Settings Simulation area6000m X 4000m Number of intersections15 Number of vehicles40-200 Average velocity5-40 mls Simulation time10,000 s Transmission range250 m Data packet size512 Byte Data rate1 Mbps

12. Simulation Result