# The Concept regarding Vehicular Communications Based on Visible Light Communication and the IoT
## 2 Methodology and Design Parameters
Summaries of all the RF techniques are provided in Table 1, where we show how they can be used under different traffic density conditions, and in Table 2, where other related work is addressed. The proposed solution could make major contributions to the emergency transmission of priority messages, the avoidance of road accidents, and the safety and security of data. In all these processes, it is extremely important to also consider the adoption of vehicular ad hoc network (VANET) technology, which can guarantee the safety of vehicles and transmits information through central roadside units (RSUs) or electronic control units (ECUs) that can pre-secure data with up to six encryption cycles [42]. With vehicular ad hoc networks (VANETs), it is possible to manage multiple vehicles that have on-board units or roadside units, as illustrated in Figure 2. Further measures at the security level could involve Euclidean distance calculation components, which can provide data on the distance between vehicles and RSUs or on the occurrence of adverse events at the edge of the road surface. Therefore, the protocols used to secure data could be based on event detection crawling and information filtering procedures, sending the data only through repetitive loops to the RSU-type units or concatenating the input data with the output data to encrypt them. If an accident is detected, the system sends the information to nearby vehicles and, through a filtering process that also uses an advanced driver-assistance system (ADAS), implements assistance processes, even providing traffic updates. Data are pre-swapped and routed through band-switching to ensure security and privacy, then initialized and keyed into the cloud. Any sudden change in the amount of data or any data modification result in a software trigger that processes each routine and compares it with the additional sets [43; 44]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Traffic Networks** & **RF Systems** & **Network Approaches** \\ \hline Low-density and sparse network & \
\begin{tabular}{c} Radio cognitive network \\ Short-range radio \\ Short-range radio \\ millimeter waves \\ \end{tabular} & Low \\ Vehicular network-type for densities &
\begin{tabular}{c} Short-range radio \\ millimeter waves \\ \end{tabular} & High \\ Use of high-density network & Network based on VLC radio & High \\ millimeter waves & Network based on 5G & High \\ Use of higher frequency bands (THZ) & Network based on 5G & High \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Network systems and approaches in relation to coverage. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**VLC Applicability** & \begin{tabular}{c} **VLC/Li-Fi Design** \\ **and Architecture** \\ \end{tabular} & \begin{tabular}{c} **VLC Approaches** \\ **and Proposals** \\ \end{tabular} & \begin{tabular}{c} **VLC IoT** \\ **Challenges** \\ \end{tabular} & \
\begin{tabular}{c} **Solution** \\ **Presented** \\ \end{tabular} &
\begin{tabular}{c} **Future** \\ **Perspectives** \\ \end{tabular} \\ \hline VLC systems [31] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline Vehicular systems [32] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline IoT [33] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline Safety systems [34] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline V2V and Li-Fi [35] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline IoT [36] & ✓ & ✓ & X & ✓ & ✓ \\ \hline OIoT [37] & ✓ & X & ✓ & X & X \\ \hline Industrial applications [38] & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline IoT [39] & ✓ & X & ✓ & ✓ & ✓ \\ \hline
5G and IoT [40] & ✓ & ✓ & ✓ & ✗ & ✓ \\ \hline
6G [41] & ✓ & ✓ & ✓ & X & ✓ \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Existing approaches and prospects for development.