190 likes | 306 Views
V2VCOM 2006. A Data Intensive Reputation Management Scheme for Vehicular Ad Hoc Networks. Anand Patwardhan Doctoral Candidate Department of Computer Science and Electrical Engineering University of Maryland Baltimore County. Anand Patwardhan, Anupam Joshi, Tim Finin, and Yelena Yesha.
E N D
V2VCOM 2006 A Data Intensive Reputation Management Scheme for Vehicular Ad Hoc Networks Anand Patwardhan Doctoral Candidate Department of Computer Science and Electrical Engineering University of Maryland Baltimore County Anand Patwardhan, Anupam Joshi, Tim Finin, and Yelena Yesha
Outline • Data management in VANETs • Security perspective • Trust-based security • Distributed data-intensive reputation management • Algorithm for screening data • Simulation results
GPS satellite Localized and distributed Wireless Access points Hazard warnings, Detours, Inclement weather, Road conditions, Traveler info. Localized Info-Stream Services Various forms of connectivity Location & directions GSM, GPRS, EDGE, E-VDO WiMax GPS VANET connectivity Update propagation • Onboard Computer • with various sensors: • GPS location • Cameras • Engine Condition • Tire pressure etc. Situation Awareness allows Adaptation
Objectives • Objectives • Situation awareness for smart-vehicles • adapt to current conditions • optimal utilization of surface transport infrastructure • Provisioning context sensitive travel information locally and directly • a growing need to provide context-sensitive information to mobile handheld devices and car-computers with travel related information) • Distributed control and fault tolerance • ensure continued functioning in face of infrastructure failures arising from natural calamities or terrorist attacks • Prevalent Enabling Technologies • Smart cars with arrays of sensors (GPS, cameras, etc.) • Multimodal wireless communication (GSM, WiFi etc.) • Distributed sensor networks embedded in the transport infrastructure
Background • Highly dynamic conditions • Lack of centralized trust authority • Data and security guarantees • Information processing and decision making • Distributed collaborative processes • Softer security guarantees • Trust based security
Dynamic conditions • Network • Mobility of devices • Arbitrary topologies • Limited connectivity • Mobility • Time frames important (message transmission and surface velocity) • Radio ranges, interference, and obstructions • Environment • Road conditions, congestion, inclement weather, hazards etc.
Trust and Risk Management • Conventional PKI, variants, or Web-of-Trust (PGP) infeasible • Limited connectivity • I&A difficult • No guarantees of intent • Security properties • Confidentiality, integrity – cryptographic methods • Availability – multiple sources, epidemic updates • Reliability of source? • Malicious entities, selfish-interest, non-cooperative nodes?
VANET Security Perspective • Data • Authenticity, reliability (quality), and timeliness • Network • Reliable routes • Cooperative and trustworthy peers • Intrusion and fault resilience • Identification and Authentication • Unique persistent identifiers (e.g. SUCVs) • Decentralized reputation management
Examples of collaborative processes • Routing • On demand route setup • Maintenance • Data dissemination • Relay data packets for others • Caching • Intrusion detection • Reputation management • Service discovery
Stimulating collaboration • Cost of collaboration • Storage • Communication • Reputation management • Self-interest • What is the payoff? (incentives) • Higher availability (cooperation) • Improved response times • Reliability • Reciprocity (tit-for-tat) • Avenues for recourse
Data dissemination model • Anchored sources (trusted) carousel information updates • Mobile devices propagate these further via epidemic updates (collaboration) • Burden of collecting relevant information and verifying it is placed on the consumer devices • Validation of data is achieved either • Trusted source (trivial case) • Agreement • Post-validation by trusted source
Simulation setup • Glomosim v. 2.0.3 • Transmission range 100m • Simulated area: Dupont Circle, Washington DC • Geographic area of 700m by 900m • 802.11 • Mobility speeds 15 to 25 m/s • Pause times of 0 to 30 s • 38 anchored resources (trusted) • 50 to 200 mobile devices (vehicles) • Simulation time: 30 mins
Autonomous and Assisted Trusted sources only Trusted sources and assisted
Effect of malicious nodes 0% malicious 30% malicious 60% malicious
Ongoing and Future work • Distributed data-intensive reputation management • Trust relationships built using persistent identities for further trustworthy collaboration: • Basis for Distributed intrusion detection • Service discovery • Reciprocative/adaptive levels of cooperation • Contention management • Adaptive radio-ranges to increase throughput