## 2 Literature Review
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Ref. No.** & **Key Contribution** & **V2V** & **V2X** \\ \hline
[31] & \multicolumn{2}{c}{AI transmission scheduling in cognitive vehicular communication and vehicular} \\  & & communication modes & \\ \hline
[32] & Resource allocation and power-sharing with several optimal resource allocation algorithms & \\ \hline
[33] & Mobile edge computing framework and a network paradigm with predictive off-loading & \\ \hline
[34] & Hierarchy of wireless networks and network standards, cumulative smart grid model, and IoT security analysis & \(\divide\) & \(\divide\) \\ \hline
[35] & Models and communication channel measurement metrics for wireless infrared networks & \(\divide\) & \(\divide\) \\ \hline
[36] & Longitudinal safety assessment of connected vehicles and intelligent driver model in a connected vehicle network & \(\divide\) & \(\divide\) \\ \hline
[37] & Survey on V2V-based vehicular sensor networks communications and discussion on issues and challenges in V2C communication & \(\divide\) & \(\divide\) \\ \hline
[38] & A physical layer perspective of vehicular communications & \(\divide\) & \(\divide\) \\ \hline
[39] & A short-range model for vehicle-to-vehicle communication on Vehicular AdHoc Networks & \(\divide\) & \(\divide\) \\  & through the showcase of Vehicle-to-Vehicle communication probability analysis & \(\divide\) & \(\divide\) \\ \hline
[40] & A hybrid clustering algorithm and simulation of the proposed algorithm on SUMO & \(\divide\) & \(\divide\) \\ \hline
[41] & A distributed cloud structure for urban traffic management through a cloud service & \(\divide\) & \(\divide\) \\  & handled message algorithm & \(\divide\) & \(\divide\) \\ \hline
[42] & Implementation of the Markov renewal process and classification of message passing & \(\divide\) & \(\divide\) \\  & between Road Side Units (RSU) and vehicles & \(\divide\) & \(\divide\) \\ \hline
[43] & Proposed a Cell Transmission Model for expressway traffic & \(\divide\) & \(\divide\) \\ \hline
[42] & Proposed a distributed cloud-based architecture for Vehicular AdHoc Networks & \(\divide\) & \(\divide\) \\  & performance and an additional mathematical model for solid communication of vehicles & \(\divide\) & \(\divide\) \\ \hline
[42] & A secure communication scheme for Vehicular AdHoc Networks & \(\divide\) & \(\divide\) \\ \hline
[44] & Highlighted the difficulties in implementing VANET systems due to traffic, communication, and safety concerns, and investigated how machine learning techniques may help address these challenges & \(\divide\) & \(\divide\) \\ \hline
[45] & Maximized global criteria while simultaneously boosting class longevity, information transmission speed, and lowering inter-class overload and provided an Efficient Key Management Scheme (KMSUNET) based on symmetric and asymmetric encryption to solve the performance and security issues of the UVANET environment & \(\divide\) \\ \hline
[46] & The suggested approach aims to establish reliable and steady clusters contributing to the network’s overall reliability & \(\divide\) & \(\divide\) \\ \hline
[47] & Over time, the percentage of malicious nodes in a vehicle AdHoc network may be reduced thanks to this scheme’s capability to identify and remove them & \(\divide\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Related Work Comparison. Table 3 compares related works on Vehicular Communication with paper reference, publishing year, and significant contribution attributes. (\(\blacktriangledown\)) indicates that the topic is covered completely, whereas (\(\blacktimes\)) means no discussion is present, and (\(\bigstar\)) conveys that the topic is covered partially. Routing protocols are crucial in vehicular AdHoc networks, facilitating message transmission between nodes and enabling various services. Two main categories of VANET routing protocols exist: Topological Routing Protocols (TRPs) and Geographic Routing Protocols (GRPs). TRPs focus on maintaining data links and disseminating topological data.