130 likes | 258 Views
Secure Local Data Aggregation and Delay Tolerant Dissemination in VANETs. Presented by Cesar Ghali Sky Faber Kyle Benson Quan Nguyen University of California, Irvine CS 234 – June, 2012. Introduction. Distributed event detection in Vehicular Adhoc NETworks
E N D
Secure Local Data Aggregation and Delay Tolerant Dissemination in VANETs Presented by Cesar Ghali Sky Faber Kyle Benson Quan Nguyen University of California, Irvine CS 234 – June, 2012
Introduction • Distributed event detection in Vehicular AdhocNETworks • Interested in detecting vehicle crash events • Collision will affect both nearby vehicles and vehicles approaching the site • Other vehicles may be present during such an event • May flood the wireless channel with crash data
Data Aggregation • Minimize the amount of power consumed by radio transmissions • Extend the battery life • Reduce communication overhead
Data Aggregation - Solutions • Minimum spanning trees (MST) • Maximize the degree • Maximize the number of hops • Leader election algorithm • Address the collision transmission problem in wireless networks • Time-constrained data transmission • Ensure that all data eventually reaches the sink
Data Aggregation - Solutions • Flow updating • Broadcast- and gossip-based • Exploit the symmetry of the network flows • Hierarchical aggregation • Based on the distance form the origin
Data Dissemination • Broadcast data to the local subsetnetwork • Locality • Quickly • Efficiently
Data Dissemination - Solutions • Flash dissemination • Broadcast as fast as possible • Not scalable • CREW • Gossip-based • Prevent receiving multiple copies of the same message • Scalable
Security Concerns • Jamming attack • Interfere the radio channel • Hidden vehicle • Adversary pretend to be in better position for broadcast • Results: stop broadcasting
Security Concerns • Wormhole attack • Tunneling message from area A to area B using fast external channel • Authentic messages sent • Trick vehicles in area B • Sybil attack • Multiple fake identities • Fake positions
Contributions • Design a protocol for event detection in VANETs • Initial event detection • Dissemination • Simulation on NS3
Algorithm and System Design • Authentication of original event data • Based on flash dissemination • Built on top of a graph topology • Multiple observers agreement • Data integrity • Non repudiation • Designed for quick dissemination for most likely affected vihecle