1. Connectivity-Aware Routing (CAR) in Vehicular Ad Hoc Networks Valery Naumov, Thomas R. Gross ETH Zurich, Switzerland IEEE INFOCOM 2007

2. Outline Introduction Connectivity-Aware Routing (CAR) Performance evaluation Conclusion

3. Introduction Ad hoc networks operate without a predefined fixed infrastructure. Vehicular ad hoc networks using 802.11-based WLAN technology have recently received considerable attention in many projects

4. Introduction - Related Work Geographic Routing (GR) –GPSR Non-GR –AODV

5. Introduction - AODV AODV (Ad-hoc On-demand Distance Vector) s d b a f e c Destination Node Source

6. Introduction - Motivation SE A B D

7. Introduction - Goal Present a novel position-based routing scheme –Find connected paths between source and destination pairs –Locate position of destination

8. Connectivity-Aware Routing (CAR) Neighbor tables and adaptive beaconing Destination location discovery Path maintenance Routing error recovery

9. Neighbor tables and adaptive beaconing all nodes include in the periodic HELLO beacons information about –moving directions –Speeds A B Neighbor Table B A

10. Neighbor tables and adaptive beaconing

11. Scenario S D

12. S D

13. Anchor Point A BB Anchor Hello Beacon

14. A Destination location discovery B C Neighbor Table B, C Source Node

15. Destination location discovery A Anchor

16. Path Maintenance S E A D

17. S E A D

18. If an end point node (Source or Destination) changes its direction End Point Node Standing Guards

19. Path Maintenance If an end point node (Source or Destination) changes its direction End Point Node Standing Guards

20. Path Maintenance If an end point node (Source or Destination) changes its direction End Point Node Standing Guards

21. Path Maintenance End Point Node Traveling Guards

22. Path Maintenance End Point Node Traveling Guards

23. Routing error recovery Gap

24. Routing error recovery Timeout Algorithm Gap AA Temporary Destination

25. Routing error recovery Timeout Algorithm AA Temporary Destination

26. Routing error recovery If an end point node (Source or Destination) changes its direction End Point Node

27. Routing error recovery End Point Node Anchor Node Walk-Around Error Recovery

28. Performance evaluation Simulatorns-2 Communication range - city scenarios Communication range - highway scenarios 400 meters 500 meters Vehicle Density less than 15, 30-40, more than 50 vehicles/km Data Rate 2 Mbps

29. Packet Delivery Ratio GPSR GPSR+AGF CAR CAR+WA Low (<15) Medium 30-40 High >50 Packet Delivery Ratio

30. GPSR GPSR+AGF CAR CAR+WA Low (<15) Medium 30-40 High >50 Packet Delivery Ratio

31. Average Data Packet Delay GPSR GPSR+AGF CAR CAR+WA Low (<15) Medium 30-40 High >50 Average Data Packet Delay (s)

32. Average Data Packet Delay GPSR GPSR+AGF CAR CAR+WA Low (<15) Medium 30-40 High >50 Average Data Packet Delay (s)

33. Routing Overhead GPSR CAR CAR+WA Low (<15) Medium 30-40 High >50 Routing Overhead in Packets

34. Routing Overhead GPSR CAR CAR+WA Low (<15) Medium 30-40 High >50 Routing Overhead in Packets

35. Conclusion A new Connectivity-Aware Routing protocol for VANETs –A scalable low overhead routing algorithm –Find connected paths between source and destination pairs –Locate position of destination

36. Thank You!!!