# A Terminal-Oriented Distributed Traffic Flow Splitting Strategy for Multi-Service of V2X Networks
## 5 Simulation Results
### Service Shunting Scheme Based on Queuing Theory  
In the heterogeneous network scenario, the performance of the adaptive shunting algorithm is simulated and analyzed for different characteristics of the vehicle network service, then compared with the load balancing algorithm [24] to verify the feasibility and effectiveness of the proposed TFSS algorithm. Figure 4 compares the service offload performance results when the load balancing and traffic flow splitting algorithm are applied to delay-sensitive services and cost-sensitive services, respectively. The delay-sensitive service assumes \(\eta_{1}=0.8\), \(\eta_{2}=0.2\). The cost-sensitive service assumes \(\eta_{1}=0.2\), \(\eta_{2}=0.8\). It is also assumed that there are three data links in the heterogeneous network, that is, \(n=3\), and their available resources are 2 Mb/s, 3 Mb/s, and 4 Mb/s, respectively. The network cost is 3, 2, and 1, respectively. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Service Scenario** & **Service Classification** & **V2X Service Mode** \\ \hline \multirow{8}{*}{IN-V} & Driving behavior data & V2B + V2R \\  & Paying behavior data & V2B + V2R \\  & Travel behavior data & V2B + V2R \\  & Vehicle info data & V2E (IN-V) + V2R \\  & In-vehicle monitoring data & V2E (IN-V) + V2R \\  & Vehicle real-time location data & V2B + V2R \\  & Vehicle operation data & V2B + V2R \\ \hline \multirow{4}{*}{OUT-V} & Vehicle to pedestrian & V2E (OUT-V) \\  & Vehicle to traffic fight & V2E (OUT-V) \\ \cline{1-1}  & Crowdsourcing road condition data & V2E (OUT-V) \\ \cline{1-1}  & Out-of-vehicle monitoring data & V2E (OUT-V) \\ \hline V2V & Vehicle to vehicle communication & V2V + V2R \\ \hline \multirow{4}{*}{User service} & In-vehicle information service (information, \multirow{2}{*}{V2R + V2 MT + V2B} \\  & games, internet video, etc.) & V2R + V2 MT + V2B \\ \cline{1-1}  & Pushing cloud information (V2T and user \multirow{2}{*}{V2R + V2 MT + V2B} \\  & terminals connected to V2T) & V2R + V2 MT + V2B \\ \hline \multirow{4}{*}{Road data service} & High resolution satellite images & V2E + V2R \\ \cline{1-1}  & Aerial photography data & V2E + V2R \\ \cline{1-1}  & Road infrastructure data & V2E + V2R \\ \hline \hline \end{tabular}
\end{table} 
Table 1: V2X-based service classification. In Figure 4, the smaller the value of the utility function, the better the shunt energy efficiency. The proposed adaptive shunting algorithm is feasible for both delay-sensitive and cost-sensitive services, and the service offload performance is better than the load balancing algorithm. Moreover, with the increase of the speed requirement of the V2X services, the value of the F-utility function value clearly increases. This indicates that as the data rate of the terminal service increases, the service demand is allocated to three wireless links, that is, the algorithm is effective and the terminal service is shunted. It can also be seen from Figure 4 that when the service rate demand of the terminal is low, the cost-sensitive service will achieve better system energy efficiency, i.e., will have a lower F-utility function value. When the value of the V2X service date is increased to about 2.5 Mbps, the system of the delay-sensitive service is more efficient than the cost-sensitive service. Therefore, we believe that when there are more service requirements in V2X heterogeneous networks, delay is a key factor in determining system energy efficiency compared to cost factors. The system delay comparison of the proposed adaptive service shunting algorithm in different scenarios of V2X service rate requirements is provided in Figure 5. The system delay of the adaptive shunting strategy is always lower than the load balancing algorithm. This is because the adaptive shunting algorithm accounts for the delay factor in the system, and the load balancing algorithm does not consider the service characteristics (assuming the system has the same transmission delay).