## 5 Conclusions  
The evaluation of throughput performance for different VANET routing protocols in city and highway scenarios reveals critical insights into the behavior of TOM and DEM profiles. Through this analysis, we observed that data throughput is a vital factor for ensuring reliable and efficient vehicle interconnection in Smart Cities. The throughput performance is influenced by key parameters such as traffic generation, packet sizes, mobility speeds, and pause times. Our numerical results show that AODV:DEM achieves a peak throughput of 3.4 Mbps in highway scenarios compared to 3.1 Mbps for AODV:TOM and 2.7 Mbps for traditional AODV. Similarly, in city scenarios, GPSR:TOM achieves a peak throughput of 3.2 Mbps, surpassing GPSR:DEM at 3.0 Mbps and the baseline GPSR at 2.8 Mbps. These values demonstrate that TOM and DEM profiles improve throughput by an average of 15% to 20% compared to traditional protocols, respectively. The results indicate that data throughput is essential for supporting critical Smart City applications such as traffic management, accident avoidance systems, and autonomous vehicle communication. High data throughput ensures real-time information exchange, reduces latency, and improves the overall performance of VANETs. For example, increasing packet sizes from 512 bytes to 1024 bytes results in a throughput improvement of approximately 12% for GPSR:TOM in city scenarios. Additionally, the throughput variation between city and highway for GPSR:TOM remains below 0.005 Mbps across various mobility speeds, indicating stable performance. In addition to protocol performance, the study shows that increasing packet sizes results in higher throughput, with GPSR:DEM achieving linear improvements. Specifically, GPSR:DEM throughput increases from 2.5 Mbps to 3.0 Mbps as packet sizes increase from 256 bytes to 1024 bytes, respectively. For different pause times, GPSR:DEM maintains a throughput of 3.1 Mbps for pause times up to 200 s, while GPSR:TOM shows steady improvements across all pause times with a minimal variation of 0.004 Mbps. Mobility speeds also impact throughput performance, with AODV:DEM showing a peak throughput of 3.4 Mbps at 100 km/h in highway scenarios, compared to 3.2 Mbps for GPSR:TOM. However, GPSR:TOM maintains more stable throughput variations across speeds, highlighting its robustness in dynamic environments. The observed throughput variation for AODV:DEM is around 0.003 Mbps at lower speeds and exceeds 0.004 Mbps for speeds above 100 km/h. In conclusion, optimizing throughput in VANETs is critical for achieving efficient vehicle interconnection in Smart Cities. The implementation of advanced routing protocols, such as TOM and DEM profiles, ensures reliable data transmission, which is essential for supporting real-time applications in intelligent transportation systems. Future research should focus on further enhancing protocol adaptability and exploring new methods to minimize throughput variations across different urban and highway scenarios. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/computers14020056/s1](https://www.mdpi.com/article/10.3390/computers14020056/s1)]([https://www.mdpi.com/article/10.3390/computers14020056/s1](https://www.mdpi.com/article/10.3390/computers14020056/s1)). Table S1: Evaluated protocols based on the experimental studies. A.K.Y.D., software, conceptualization; A.E.T.A., software, conceptualization; N.M.O.S.A., formal analysis, methodology; A.F., formal analysis, methodology; L.S.A., investigation; F.A.E.A., formal analysis, methodology; A.I.G.E., formal analysis, methodology; M.E.E., funding acquisition, validation; T.A., supervision, funding acquisition. All authors have read and agreed to the published version of the manuscript. The authors extend their appreciation to the Deanship of Research and Graduate Studies at King Khalid University for funding this research through a Large Research Project under grant number RGP2/212/45.