Secure and efficient broadcast communication system in vehicle ad-hoc networks

Vehicle ad-hoc networks (VANETs) have gained importance in recent times due to the advent of the Internet of Things (IoT), which emphasise the connectivity of physical devices in the human world. Services, such as traffic congestion and accident alerts, are just two of the most important applications introduced by VANETs. These applications required a specific type of communication called broadcasting. Broadcast Communication (BC) is established by dissemination of information to all the vehicles in a network to achieve Network Coverage (NC). The BC in VANETs face many different challenges, including security and efficiency of packing transmission in multi-hop BC highway and urban scenarios.
On-Board Units (OBUs) with a maximum communication range of 1000 metres are used in vehicles to establish communication. Due to the limited range of OBUs, a single transmission from a vehicle is unable to achieve NC. In order to achieve NC, the vehicle named the Source Vehicle (SV), requires help from other vehicles called Relay Vehicles (RV), to retransmit the same packet. An environment where a packet has to be retransmitted by other nodes falls under the category of a multi-hop environment. The important issue faced by retransmission in BC is known as the Broadcast Storm Problem (BSP), which creates network congestion leading to delays in the propagation of packets. The BSP is caused by blind retransmission by RVs to achieve NC.
There are two options to avoid BSP in VANET BC multi-hop environments No-Retransmissions (NoR) and Efficient BC System (EBCS). The NoR option consists of stopping retransmission, which effectively kills multi-hop BC. On the other hand, the EBCS proposes the concept of an Optimised RV Selection (ORVS) mechanism to avoid the BSP without compromising NC. To develop EBCS, this study investigates algorithms and techniques to produce ORVS mechanisms for both highway and urban topologies. The limitations of the available mechanisms proposed in the literature have also been analysed during this research. Two different techniques/algorithms the Multi-Objective Genetic Algorithm (MOGA) and Evolutionary Game (EG) are proposed in this thesis to produce ORVS mechanisms. The MOGA and EG are comprised of novel fitness functions for the purpose of selecting the best suited ORVS mechanism to achieve the development of EBCS.
Finally, security related to packet transmission in BC systems have been investigated by establishing a secure BC system. To establish a secure BC system, a secure layer-based architecture is proposed to secure transmitted packets. In this thesis, the secure layer-based architecture is combined with ORVS mechanisms to create a secure and efficient BC system in VANETs.