Optimized Throwbox Deployment for Enhancing Delivery Ratio and Overhead Cost Performance in VDTN

The lack of sufficient contact opportunities in sparse vehicular delay tolerant networks results in poor performance. The network performance can be enhanced by deploying additional small wireless devices called throwbox. Nonetheless, the deployment of throwboxes with distinct placement strategies results in diverse outcomes in terms of metrics such as delivery ratio (DR), delay, and overhead cost (OC). In this paper, the throwbox deployment problem has been presented as an optimization problem. A customized binary differential evolution (CBDE)-based iterative optimization method is employed to improve the DR. Furthermore, depending upon a specific application, it might be desired to have a balanced performance that optimizes the trade-off between different metrics. Therefore, the employment of a multi-objective CBDE (MOCBDE) technique is proposed to optimize the trade-off between DR and OC metrics. The proposed approaches are implemented using Matlab and opportunistic network environment simulator. The experimental results presented in the paper validates the superiority of the proposed CBDE approach over existing methods of throwbox deployment. In addition, the MOCBDE approach provides a set of non-dominated (also called pareto-optimal) solutions with an exhaustive view of desirable results. Consequently, depending on the application requirements, the method allows selecting suitable locations for throwbox deployment.