Speeding Up the Evaluation of a Mathematical Model for VANETs Using OpenMP - Simulation and Modeling Methodologies, Technologies and Application - page 20

Speeding Up the Evaluation of a Mathematical Model
for VANETs Using OpenMP

Carolina Garcıa-Costa, Juan Bautista Tomas-Gabarr on, Esteban Egea-L opez, and
Joan Garcıa-Haro

Department of Information and Communications Technologies,
Universidad Politecnica de Cartagena (UPCT), Plaza del Hospital 1, Cartagena, Spain
{ carolina.garcia,juanba.tomas,esteban.egea,joang.haro } @upct.es

Abstract. Vehicular Ad-hoc Networks (VANETs) are having a significant im-
pact on Intelligent Transportation Systems, specially on the improvement of road
safety. Cooperative/Chain Collision Avoidance (CCA) application comes up as a
solution for decreasing accidents on the road, therefore it is highly convenient to
study how the system of vehicles in a platoon will behave at different stages of
technology deployment until full penetration in the market. In the present paper
we describe an analytical model to compute the average number of accidents in
a chain of vehicles. The use of this model when the CCA technology penetra-
tion rate is not 100% leads to a vast increase in the number of operations. Using
the OpenMP directives for parallel processing with shared memory we achieve a
significant reduction in the computation time consumed by our analytical model.

Keywords: OpenMP, VANET, Supercomputing, Cooperative/Chain Collision
Avoidance application.

1 Introduction

Vehicular networks, also known as VANETs, are defined as ad-hoc mobile networks
with two main communication features. On the one hand, VANETs are in charge of
transmitting information among vehicles (V2V communications). In this first case, cars
carry out the information interchange without any infrastructure support for regulating
the access. On the other hand, an intercommunication among vehicles and infrastruc-
tures also exists (V2I communications), making possible a connection through cars and
a backbone network, reaching in this way those vehicular entities allocated out of the
direct communication range.
One of the aims of vehicular networks development is the improvement of road
safety. The main goal of these innovative systems is to provide drivers a better knowl-
edge about road conditions, decreasing the number of accidents and their severity, and
simultaneously aiding to a more comfortable and fluent driving. Other vehicular ap-
plications are also considered, such as Internet access, driving cooperation and public
information services support.
A Cooperative/Chain Collision Avoidance (CCA) application [1] uses VANET com-
munications for warning drivers and decreasing the number of traffic accidents. CCA