Verifying Safety Messages Using Relative-Time and Zone Priority in Vehicular Ad Hoc Networks.

Sam Banani,Steven Gordon,Surapa Thiemjarus,Somsak Kittipiyakul

doi:10.3390/s18041195

Abstract

In high-density road networks, with each vehicle broadcasting multiple messages per second, the arrival rate of safety messages can easily exceed the rate at which digital signatures can be verified. Since not all messages can be verified, algorithms for selecting which messages to verify are required to ensure that each vehicle receives appropriate awareness about neighbouring vehicles. This paper presents a novel scheme to select important safety messages for verification in vehicular ad hoc networks (VANETs). The proposed scheme uses location and direction of the sender, as well as proximity and relative-time between vehicles, to reduce the number of irrelevant messages verified (i.e., messages from vehicles that are unlikely to cause an accident). Compared with other existing schemes, the analysis results show that the proposed scheme can verify messages from nearby vehicles with lower inter-message delay and reduced packet loss and thus provides high level of awareness of the nearby vehicles.

Highlights

Vehicular ad hoc networks (VANETs) aim to improve road safety and traffic efficiency by providing communications among vehicles and between vehicles and infrastructure
With a signature verification time of an average of 5 ms [5,6] or equivalently 200 messages per second, about 95% of the time the verification rate is too low to verify all messages. This figure confirms that message prioritization is required
Note that the 5 ms verification time is the number in 2009–2013, today’s number might be 2 ms, which gives 500 messages verified per second

Summary

Introduction

Vehicular ad hoc networks (VANETs) aim to improve road safety and traffic efficiency by providing communications among vehicles and between vehicles and infrastructure. In order to exchange messages about traffic conditions, an important requirement is to verify that messages are from valid sources. One application requiring safety messages is cooperative safety driving. The application needs to be aware of the statuses of other vehicles (e.g., position, velocity and direction) in order to warn the driver about possible safety incidents. Many proposed standards require vehicles to periodically broadcast safety or awareness messages, for example, Basic Safety Message (BSM) in Wireless Access in Vehicular Environment (WAVE) standard [3], or Cooperative Awareness Messages (CAMs) in European Telecommunications Standards Institute (ETSI) standard [4]

Methods

Results

Conclusion