1. Mini-Project 2006 Secure positioning in vehicular networks based on map sharing with radars Mini-Project IC-29 Self-Organized Wireless and Sensor Networks Csaba Árendás Tutors: Maxim Raya Prof. Jean-Pierre Hubaux

2. Mini-Project 2006 2 Motivation Positioning –Positioning without need for strong evidence –Navigation systems –GPS, GSM Secure positioning –To be sure that the position is correct –Military applications (smart bombs) Secure positioning in vehicular network –Collision warning –Life critical application

3. Mini-Project 2006 3 Problem statement – secure positioning in vehicular networks

4. Mini-Project 2006 4 Solution overview Precise distance measurement –ACC radars, relative positions Position authentication –Position keys ID authentication –Conventional cryptography –Public key cryptography Communication –Radar communication –DSRC broadcast radio communication

5. Mini-Project 2006 5 System model, assumptions Precise ACC radars –Precise distance measurement, –Radar communication –Vehicle's 360 degrees area is covered Broadcast radio communication device TPD for each vehicle –Contains Certificate, ID, public, private keys –Issued by CA at the police station –Given with the number plate registration –Hash, sign, verify a message, RND generation

6. Mini-Project 2006 6 State of the art Adaptive cruise control systems

7. Mini-Project 2006 7 Generation of the position key - ideal case

8. Mini-Project 2006 8 Generation of the position key - real case Since the other vehicle front side figure (or other side) is not a standard the distance measurements might differ from each other The key length in this way is limited by the maximal distance measurement difference

9. Mini-Project 2006 9 Generation of the position key - final solution

10. Mini-Project 200610 Mutual neighbor authentication

11. Mini-Project 200611 Neighbor map broadcasting (DSRC)

12. Mini-Project 200612 Neighbor map sharing, world map assembly

13. Mini-Project 200613 Evaluation Necessary sensors with minimal precision Effect of precision on position key length Position error Effect of digital signature computation time

14. Mini-Project 200614 Environment sensors

15. Mini-Project 200615 Effect of precision on key length

16. Mini-Project 200616 Position error

17. Mini-Project 200617 Effect of digital signature computation time

18. Mini-Project 200618 Conclusion Independent positioning from other systems, real ad hoc network –Precise positioning (not as distance bounding) –Scalable system Shared map –Containing IDs, distances, speed –Therefore location of a broadcasted emergency message is easy, collision avoidance is possible Strongly valuable against attacks –Position keys –Directional antennae

19. Mini-Project 200619 Back up slides

20. Mini-Project 200620 Problem statement – secure positioning in vehicular networks

21. Mini-Project 200621

22. 22 Synchronized positioning and authentication

23. Mini-Project 200623 Authentication without angle communication measurement

24. Mini-Project 200624 Distance measuring the radar and the measuring surface are on one axis (ideal case) Since both partners are measuring the same distance it is easy to use it as a key The length of the key is limited by the precision of used radars

25. Mini-Project 200625 Distance measuring problem The radar and the measuring surface are not on the same axes The radar`s position is not on the surface of the vehicle The radars are embedded in the front side of the vehicle –Exact position might differ from vehicle to vehicle –With factory calibration this problem is solvable

26. Mini-Project 200626 Distance measuring problem we might measure the different distance Since the other vehicle front side figure (or other side) is not a standard the distance measurements might differ from each other The key length in this way is limited by the maximal distance measurement difference

27. Mini-Project 200627 Distance measuring problem (solution one) closest point detection factory calibration is necessary Calibrating my most exterior point (factory calibration) –Not easy to do it precisely since sometimes the number plate is the exterior point Measuring neighbors closest point –Calculating the distance between my exterior point and between its closest point Theoretically works but –What if my exterior point is changed by a little accident –Or I use a new, different number plate

28. Mini-Project 200628 Generation of the position key - final solution