240 likes | 414 Views
Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular ad-hoc Networks. 1 Jeng-Farn Lee, 1 Chang-Sheng Wang , 1 Ming-Chin Chunag 1 Department of Computer Science and Information Engineering National Chung Cheng University, Chia-Yi, Taiwan, R.O.C. WCNC 2010. Outline.
E N D
Fast and Reliable Emergency Message Dissemination Mechanism in Vehicular ad-hoc Networks 1Jeng-Farn Lee, 1Chang-Sheng Wang ,1Ming-Chin Chunag 1Department of Computer Science and Information Engineering National Chung Cheng University, Chia-Yi, Taiwan, R.O.C. WCNC 2010
Outline • Introduction • Fast and Reliable Emergency Message Dissemination Mechanism • Performance Analysis • Conclusions
Introduction • Advanced technologies • GPS • power-saving embedded computer • wireless communication system
Introduction • A. Message Forwarding • 1) Random Time Slot • 2) Adjacency Sectors • B. Reliability • 1) ACK Frame • 2) Repetition scheme
introduction • Goals • Low dissemination delay • High reliability • How • Fast and reliable emergency message dissemination mechanism (FR-EDM)
Fast and Reliable Emergency Message Dissemination Mechanism(FR-EDM) • Assume: • Freeway • GPS • Intelligent transportation system(ITS)
FR-EDM • When a car accident happened • 1)Is it a new message ? • 2)is the message delivered from vehicle in front of me?
FR-EDM • Fast Forwarding • GPS
FR-EDM Ox: length of block Oy: wide of block Area: size of transmission area
FR-EDM • The value of block size • 4m*4m,8m*8m,16m*16m
FR-EDM • The value of block size • 4m*4m,8m*8m,16m*16m
FR-EDM • The value of block size • 4m*4m,8m*8m,16m*16m
FR-EDM • Reliability mechanism • rebroadcast n :the number of vehicles in the transmission range P:channel loss ratio
FR-EDM • Reliability mechanism • rebroadcast
Conclusions • We propose a fast and reliable emergency message dissemination mechanism (FR-EDM) • In the simulation results, our protocol achieves the low disseminating delay and high reliability while disseminating the emergency message