## 2 Literature Review
However, they face scalability issues, time-consuming discovery, complex control requirements, and cumbersome maintenance. In contrast, GRPs rely on up-to-date location information to establish connections with moving vehicles, with optional data dissemination. GRPs excel in highly dynamic, large-scale networks due to their simplicity, low overhead, superior performance, and scalability. These protocols adjust routes based on precise vehicle coordinates [53; 54; 55; 56; 57]. Figure 2 depicts the hierarchical structure of routing protocols and their key components. [PERSON] et al. proposed vehicular communication resource allocation and power sharing [32]. High capacity for V2I connections and UR for V2V links were discussed. They suggested efficient resource allocation methods for power-sharing and resource allocation. [PERSON] et al. [33] suggested a feasible vehicular network model with anticipatory off-loading. Mobile edge computing was used to describe cloud-based vehicle networks in several dimensions. They discussed the mobility and calculation time of V2V and V2I communication modalities. [PERSON] et al. [34] discussed wireless network structure and standards. They investigated a cumulative smart grid model for vehicle mobility and wireless technology. They also covered wireless technology, ranges, and IoT security. [PERSON] et al. [35] suggested wireless infrared network architectures and communication channel measurements. They examined over 20 optical wireless communication models for various communication circumstances. [PERSON] et al. [36] discussed superhighway-linked car longitudinal safety evaluation. A linked car network and high-level control algorithm revealed their intelligent driver model. They suggested time-to-collision, rear-end crash risk index, and sideswipe crash risk for three joining categories: front, rear, and cut. [PERSON] et al. and [PERSON], [PERSON], and [PERSON] [42; 58] suggested VANET privacy-preserving communication. They combined identity-based encryption with elliptic curve cryptography. Server impersonation, replay, modification, and man-in-the-middle attacks were covered. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Ref No.** & **Key Contribution** & **V2V** & **V2X** \\ \hline
[48] & A novel self-adaptive Angular-based k-medoid Clustering Algorithm (SAACS) is created to generate flexible clusters. The network latency decrease, and clusters are built using informed predictions about route lengths and signal ranges. & \(\blacktriangledown\) & \(\blacktriangledown\) \\ \hline
[49] & This comprehensive review encompasses the many methods explored in current literature as prospective solutions for addressing the pervasive problem of traffic congestion. & \(\blacktriangledown\) & \(\bigstar\) \\ \hline
[50] & Scholars are now more responsible for safeguarding individuals’ private data and information and put forward the Key Agreement Protocol for Urbanized Block Chains (UB-KAP) & \(\blacktriangledown\) & \(\bigstar\) \\ \hline
[51] & An innovative REST web service for visualizing data is proposed, and also the Fundamental Safety Messages were put through their paces in a Big Data lab. The authors discussed proper behavior concerning packet loss, packet delivery, and communication latency was shown. & \(\blacktriangledown\) \\ \hline
[52] & For this reason, the AWCP EE-WOA model analysis includes a vehicular network at a predetermined velocity and location. & \(\blacktriangledown\) & \(\bigstar\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._[PERSON] et al. [59] recommended models for cluster-based routing in Vehicular AdHoc Networks (VANETs) and a performance measurement approach for security, specifically focused on stream position analysis. Additionally, their approach for detecting Distributed Denial of Service (DDoS) attacks incorporates elements that pose a potential risk to cluster-based routing. [PERSON], [PERSON], and [PERSON] [60] analyzed VANET's cluster-based routing technology in an actual geographic scenario.