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
Mini-Project 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
Mini-Project Problem statement – secure positioning in vehicular networks
Mini-Project 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
Mini-Project 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
Mini-Project State of the art Adaptive cruise control systems
Mini-Project Generation of the position key - ideal case
Mini-Project 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
Mini-Project Generation of the position key - final solution
Mini-Project Mutual neighbor authentication
Mini-Project Neighbor map broadcasting (DSRC)
Mini-Project Neighbor map sharing, world map assembly
Mini-Project Evaluation Necessary sensors with minimal precision Effect of precision on position key length Position error Effect of digital signature computation time
Mini-Project Environment sensors
Mini-Project Effect of precision on key length
Mini-Project Position error
Mini-Project Effect of digital signature computation time
Mini-Project 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
Mini-Project Back up slides
Mini-Project Problem statement – secure positioning in vehicular networks
Mini-Project
22 Synchronized positioning and authentication
Mini-Project Authentication without angle communication measurement
Mini-Project 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
Mini-Project 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
Mini-Project 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
Mini-Project 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
Mini-Project Generation of the position key - final solution