# Intelligence-Based Strategies with Vehicle-to-Everything Network: A Review
## 3 Artificial Intelligence
### Swarm Techniques (STs)  
The combined actions of autonomous and dispersed systems are known as swarm intelligence. In a VANET, this involves an ensemble of vehicles communicating with others and the outside world. Since there is no centralized system, cars follow fundamental standards like highway architecture, speed limits, and signals. Swarm cognitive abilities consist of ant behavior, bacteria germination, bird groups, fish schools, and microbial cognition. The swarm methods are described as follows, and the advantages and issues in vehicular networks are discussed in Table 7:  
1. Particle Swarm Optimization (PSO): It is a comprehensive optimization technique that may solve problems with an individual point or entire area in a space with n dimensions. It ensures each atom chooses its preferred prior location or goes towards another one based on velocity if the latest location is superior [106].
2. Ant Colony Optimization (ACO): Graph optimization challenges of all kinds are searched for the nearest possible optimum solutions by ACO. The ants within the algorithm strive to adhere to the shortest path, as described in reference [107].
3. Stochastic diffusion search (SDS): The method was initially developed for a population-based mapping tool. It utilizes immediate interaction methods to assess the identification and aggregating hypotheses of all potential routes, including collaborative behavior observed in insect societies [108].
4. Artificial Swarm Intelligence (ASI): This refers to the collective intelligence exhibited by a group of artificial agents working together in a coordinated manner. It is an on-demand network that connects integrated human participants in distant groups. It utilizes swarm intelligence (SI) and AI techniques to balance and analyze the network using natural swarms. AI-based ASI creates a collective intelligence of human participants, enabling groups to reach results with implications exceptionally pertinent to what humans can do independently [109].  
The vast majority of swarm intelligence techniques do not involve the formulation of hypotheses about issue optimization. Moreover, using swarm intelligence facilitates the identification of methods of higher standards through the integration of path optimization and the harnessing of innate knowledge. Furthermore, swarm intelligence is renowned for its simplicity and straightforward deployment compared to alternative AI methodologies. Swarm intelligence is frequently utilized to facilitate routing optimization, including tasks such as determining the shortest path, engaging in geocast routing, and implementing clustering methods [110].  
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Swarm Types** & **Advantages** & **Uses Areas in VANET** & **Issues** \\ \hline \multirow{3}{*}{**PSO**} & No assumptions are necessary for the optimization of the problem & Optimizing routing protocols, i.e., shortest path, geocast, and clustering & Insufficient coverage and inefficient allocation of resources caused by overlapping coverage in RSUs [111] \\ \cline{2-3}  & Gradient information is not necessary for problem efficiency & Identify and recognize nodes that are intended to cause harm & Efficient and reliable multi-hop relaying routes that operate in real time; challenging task of adjusting parameters due to their great complexity [112] \\ \hline \multirow{3}{*}{**SDS**} & Uses a combination of path discovery and AI for high-quality solutions & \multirow{3}{*}{Handles traffic congestion} & Signal reception and routing efficiency are hindered (confined mobility, irregular node distribution) [113] \\ \cline{2-3}  & Straightforward, and effortless to execute & \multirow{3}{*}{Assists in mitigating routing attacks; contributes to the optimization of routing} & Complex behaviours and interactions; congestion overhead \\ \cline{1-1} \cline{3-3}  & & & \\ \hline \hline \end{tabular}
\end{table}
Table 7: Swarm methods: primary advantages, issues, and uses in the VANET domain.