Effects of VANET´s attributes on network performance

A simple flooding mechanism for broadcasting messages over vehicular ad-hoc networks causes massive message redundancy, contention and collision known as the broadcast storm problem. Most available solutions to broadcast storm are normally based on the selection of the rebroadcast nodes depending on a given single attribute such as: sender-to-receiver distance, node density, vehicle´s speed, movement direction, or number of message duplicates received. As the settings of any given attributes may remarkably impact the network performance, comparisons of such settings are therefore, an important research topic. In this paper, we suggest a simple but effective solution to the VANET broadcast storm problem through comparison of various attribute settings and select the rebroadcasting nodes based on a combination of multi- network and node attributes. To the best of our knowledge, most of the solutions to the broadcast-storm problem make use of only single-attribute schemes and do not consider on employing two or more attributes for broadcast suppression. The scheme suggested throughout this paper is valuable for two reasons: First, it is considered as a guide to select proper methods/attributes for a specific network application´s goal, e.g. maximum reachability with a reduced redundancy and/or with minimum message delay at specific network densities. Second, it sets a basis for future studies that employ multiple attributes on mitigating broadcast-storm through machine-learning-based approach. The simulation results of this proposed scheme show that a proper combination of attributes may outperform the performance of the best single-attribute-based schemes. A combined broadcast scheme which implements both distance and duplicate attributes provides a remarkable reduction on message redundancy by 41% compared to the best single distance-based attribute broadcast.