## 3 Proposed Method
### Hybrid Protocol-Based Path Selection
The average one-hop propagation distance a is influenced by the chance that there are no automobiles in the zones from \(I_{0}\) to \(I_{i}\), as represented by this equation:  
\[D_{B}=(1-h_{r}((x_{0}=0))\cdot\sum_{M=i}^{n-1}I_{M}+\sum_{i=1}^{n-1}(((1-h_{r}(x _{i}=0))\prod_{j=0}^{i-1}h_{r}(x_{j}=0))\cdot\sum_{M=i}^{n-1}I_{M}. \tag{9}\]  
And the propagation speed is as follows:  
\[P_{N}=\left(\frac{D_{B}}{B\;\frac{D}{H-D}}\right) \tag{10}\]  
In the context of a bi-directional broadcast, the emergency message is disseminated in two opposing directions, resulting in the propagation speed being influenced, as follows:  
\[P_{O}=\frac{2D_{B}}{B\;\frac{O}{H-D}} \tag{11}\]  
In a multi-directional broadcast, where each direction on an intersecting road is covered up to a length of \(I_{R}\), the average per-hop distance in one direction can be calculated as follows:  
Figure 2:0 Figure 2:1  
Multi-directionally broadcasting the propagation speed is as follows:  
Figure 2:2  
The message propagation speed for each broadcast is finally determined. 4. Best forwarder selection. In this section, we introduce an effective approach for the best forwarder selection in VANETs. The forwarding node choice takes into account the priority assigned to the packets in its transmission queue. The primary goal is to reduce delay for EM transmission while also minimizing the routing overhead cost function that guides the selection of forwarding networks. This function considers two key metrics: delay and stability, as elaborated upon in the subsequent subsection. Delay: The end-to-end delay (E2E) of a packet denotes the total time it takes for a packet to travel from its source to its destination, which in this case is node X. To calculate the link delay between two nodes, labeled as \(N_{i}\) and \(N_{j}\), and represented as \(ID_{ij}\) for the link (i,j), we consider the following factors: transmission delay \((F_{td})\), queuing delay \((Q_{d})\), and hopping delay \((H_{d})\). In essence, the link delay \(ID_{i,j}\) for the link between nodes \(N_{i}\) and \(N_{j}\) can be expressed as the sum of these individual delays:  
Figure 2:3  
This calculation helps in understanding the total delay experienced by a packet as it travels through the network between the specific pair of nodes, \(N_{i}\) and \(N_{j}\), where \(F_{td}(i)=\frac{C_{i}}{D_{B}}\) and \(Q_{d}(i)=\frac{C_{i}}{D_{R}-C_{i}}\), with \(D_{R}\) denoting the data rate and \(C_{i}\) illustrating the current buffer occupancy of \(N_{i}\) to X, denoted by \(D_{i}\), and written as follows:  
Figure 2:4  
\(path_{i}\) illustrates the routing path from \(N_{i}\) to X. Stability: To determine the connection security between two adjacent devices in VANETs, our approach uses a random waypoint model to introduce movement patterns in VANETs. In this VANET environment, each vehicle maintains a forum that records the distance measurement history of other neighboring vehicles in the time interval [0, t]. Using this historical information, the vehicle calculates the link stability at the current time, taking into account the distance traveled to all neighboring vehicles. The stability of the link between two nodes labeled \(N_{i}\) and \(N_{j}\) can be expressed as \(s_{i,j}\), given as follows:  
Figure 2:5  
\(D_{i,j}\): Distance between two nodes;  
\(N_{i}\) and \(N_{j}\): Nodes at the current time;  
\(mean(T)\): The mean of M-previous distances between \(N_{i}\) and \(N_{j}\), which is defined as follows:  
Figure 2:6  
The parameter \(s_{i,j}\) in Equation (16) represents the standard deviation, which is an indicator of the coefficient of variation. It provides a standard measure of how data points are distributed in terms of probability. When the value of \(s_{i,j}\) is close to 0, it means that the connection between two nodes is stable, and we can consider j as a stable neighbor of i. On the contrary, if \(D_{i,j}(T)\) tends to 1, it means that the distance distribution is unstable and the connection between nodes is unstable.