## 5 RC-LARR: RSU-Assisted Cloud-Based Location-Aware Hybrid Routing
### Route Discovery
This implies that the routing protocol is highly effective in adapting to these changes, ensuring reliable communication. In VANETs, the timely delivery of information is critical, especially for applications requiring real-time or near-real-time data, like traffic congestion alerts and cooperative driving. The result shows that EED was reduced as compared to the state-of-the-art protocols. The reduced EED can support time-sensitive applications more effectively, enhancing the overall safety

Figure 13:1 Load on RSUs and cloud vs. number of connections. Figure 13:2 Network reliability vs. speed. and efficiency of vehicular networks. The proposed architecture uses cloud computing and RSUs as an SDN control plane. These SDN control planes provide routing information to the node. The load on the RSUs and on the cloud significantly impacts the proposed routing protocol. The results conclude that the load on the RSUs and the cloud increased as the number of connections increased. The calculation of the time required for routing shows the efficiency and efficacy of the routing protocol. ## 9 Conclusions

In this study, a hybrid hierarchical architecture of SDN was proposed. The proposed architecture perfectly copes with problems like scalability and heterogeneity in VANETs. In this architecture, the control plane was divided into two parts: control plane layer 1 and control plane layer 2. Control plane layer 1 contains RSU-level information about the vehicle, while control plane layer 2 keeps information about the global network. To extend the network, the RSU was placed in the middle of the road, on a divider, to obtain maximum coverage. Further, cloud storage was used for control plane layer 2. A cloud-enabled RSU-based location-aware routing protocol, RC-LAHR, was proposed for the architecture in question. The time duration of the vehicle within the communication range was the selection criterion of the next hop in the route for the routing protocol. The proposed routing protocol, based on the proposed architecture, was compared with existing GPSR and OPBR protocols on different parameters like network reliability, traffic density, and route calculation time. The efficiency and efficacy of the proposed protocol were also tested on PDR and EED. The proposed routing protocol performed well as compared to GPSR and OPBR. The result shows that the EED was reduced to 20% and the PDR was increased to 30%. The network reliability also increased by up to 5% as compared to the OPBR and GPSR. ## 10 Limitations and Future Scope

Despite the promising outcomes of this study, it is important to acknowledge its limitations, which pave the way for future research directions. A major constraint of the research is the increasing load on the RSUs as connections increase. In high-density traffic conditions, this may cause bottlenecks and reduce network efficiency. Cloud storage for control plane layer 2 is advantageous for data processing; however, latency challenges arise when cloud servers are far from the RSUs. RSU load balancing methods should be improved in future studies. Real-time traffic data might be used to dynamically allocate resources or integrate edge computing to spread the processing burden. Energy constraints are a major challenge, especially for electric vehicles. Therefore, future research should also consider the energy efficiency of the network, especially focusing on the power consumption of the vehicle, RSUs, and cloud servers, aiming to develop more sustainable VANET architectures. Conceptualization, M.K. ; methodology, M.K. ; software, M.K. ; validation, M.K. ; formal analysis, M.K. ; investigation, M.K. ; resources, M.K. ; data curation, M.K. ; writing--original draft preparation, M.K. ; writing--review and editing, R.S.R. ; visualization, R.S.R. ; supervision, R.S.R. All authors have read and agreed to the published version of the manuscript. This research received no external funding. **Institutional Review Board Statement**: Not applicable. **Informed Consent Statement**: Not applicable.