Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular ad-hoc Networks

Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular ad-hoc Networks

11Jeng-Farn Lee, Jeng-Farn Lee, 11Chang-Sheng Wang ,Chang-Sheng Wang ,11Ming-Chin Ming-Chin ChunagChunag11Department of Computer Science and Information EngineeringDepartment of Computer Science and Information Engineering

National Chung Cheng University, Chia-Yi, Taiwan, R.O.C.National Chung Cheng University, Chia-Yi, Taiwan, R.O.C.

WCNC 2010WCNC 2010

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OutlineOutline IntroductionIntroduction Fast and Reliable Emergency Message Dissemination Fast and Reliable Emergency Message Dissemination

MechanismMechanism Performance AnalysisPerformance Analysis ConclusionsConclusions

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IntroductionIntroduction Advanced technologiesAdvanced technologies

GPS GPS power-saving embedded computerpower-saving embedded computer wireless communication systemwireless communication system

introductionintroduction

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IntroductionIntroduction A. Message ForwardingA. Message Forwarding

1) Random Time Slot1) Random Time Slot 2) Adjacency Sectors2) Adjacency Sectors

B. Reliability B. Reliability 1) ACK Frame1) ACK Frame 2) Repetition scheme2) Repetition scheme

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introductionintroduction GoalsGoals

Low dissemination delayLow dissemination delay High reliabilityHigh reliability

HowHow Fast and reliable emergency message Fast and reliable emergency message

dissemination mechanism (FR-EDM)dissemination mechanism (FR-EDM)

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Fast and Reliable Emergency Message Fast and Reliable Emergency Message Dissemination Mechanism(FR-EDM)Dissemination Mechanism(FR-EDM)

Assume:Assume: FreewayFreeway GPSGPS Intelligent transportation system(ITS)Intelligent transportation system(ITS)

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When a car accident happenedWhen a car accident happened 1)Is it a new message ?1)Is it a new message ? 2)is the message delivered from vehicle in 2)is the message delivered from vehicle in

front of me?front of me?

FR-EDMFR-EDM

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Fast ForwardingFast Forwarding GPSGPS

FR-EDMFR-EDM

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FR-EDMFR-EDM

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Ox: length of blockOy: wide of blockArea: size of transmission area

FR-EDMFR-EDM The value of block sizeThe value of block size

4m*4m,8m*8m,16m*16m4m*4m,8m*8m,16m*16m

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FR-EDMFR-EDM The value of block sizeThe value of block size

4m*4m,8m*8m,16m*16m4m*4m,8m*8m,16m*16m

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FR-EDMFR-EDM The value of block sizeThe value of block size

4m*4m,8m*8m,16m*16m4m*4m,8m*8m,16m*16m

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FR-EDMFR-EDM

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FR-EDMFR-EDM

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FR-EDMFR-EDM Reliability mechanismReliability mechanism

rebroadcastrebroadcast

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n :the number of vehicles in the transmission rangeP:channel loss ratio

FR-EDMFR-EDM Reliability mechanismReliability mechanism

rebroadcastrebroadcast

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Performance AnalysisPerformance Analysis

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Performance AnalysisPerformance Analysis

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Performance AnalysisPerformance Analysis

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Performance AnalysisPerformance Analysis

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ConclusionsConclusions We propose a fast and reliable emergency We propose a fast and reliable emergency

message dissemination mechanism (FR-EDM)message dissemination mechanism (FR-EDM) In the simulation results, our protocol achieves In the simulation results, our protocol achieves

the low disseminating delay and high reliability the low disseminating delay and high reliability while disseminating the emergency messagewhile disseminating the emergency message

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