The growing adoption of urban video surveillance and traffic monitoring increases demand for low‑latency, cost‑efficient, and privacy‑preserving analytics. Pure cloud offloading introduces network bottlenecks and unacceptable end‑to‑end delay for time‑critical use cases. We evaluate a hybrid edge–cloud architecture that performs preliminary inference at the edge and delegates aggregation, visualization, and archival tasks to the cloud. Using Raspberry Pi–class devices and a managed cloud back end, we benchmark latency, bandwidth consumption, CPU utilization, and accuracy on representative urban scenes (intersections, pedestrian zones, parking lots). Compared to cloud‑only processing, the proposed hybrid approach reduces median latency by 71% and bandwidth by 94%, while maintaining accuracy within 3–5% of full‑precision models. We discuss design trade‑offs, security and privacy considerations, and deployment guidance for city‑scale systems.

Edge computing; Cloud computing; Hybrid architecture; Smart cities; Real‑time video analytics; Object detection; MQTT; Latency; Bandwidth optimization; Privacy.

W. Shi, J. Cao, Q. Zhang, Y. Li, and L. Xu. 2016. Edge computing: Vision and challenges. IEEE Internet of Things Journal 3, 5, 637–646.

M. Satyanarayanan. 2017. The emergence of edge computing. Computer 50, 1, 30–39.

R. Deng, R. Lu, C. Lai, T. Luan, and H. Liang. 2016. Optimal workload allocation in fog‑cloud computing toward balanced delay and power. IEEE IoT J. 3, 6, 1171–1181.

B. Varghese and R. Buyya. 2018. Next generation cloud computing: New trends and research directions. Future Generation Computer Systems 79, 849–861.

J. Redmon and A. Farhadi. 2018. YOLOv3: An incremental improvement. arXiv:1804.02767.

A. Howard et al. 2017. MobileNets: Efficient CNNs for mobile vision applications. arXiv:1704.04861.

C. Zhang, Y. Zheng, and L. Qi. 2022. Edge‑cloud collaborative intelligence for real‑time video analytics. IEEE TII 18, 4, 2952–2961.

J. Liu, H. Shen, and Y. Yu. 2021. Bandwidth‑aware task offloading for smart surveillance. IEEE IoT J. 8, 7, 5473–5485.

J. Gubbi, R. Buyya, S. Marusic, and M. Palaniswami. 2013. Internet of Things (IoT): A vision... FGCS 29, 7, 1645–1660.

A. Bochkovskiy, C.‑Y. Wang, and H.‑Y. M. Liao. 2020. YOLOv4: Optimal speed and accuracy of object detection. arXiv:2004.10934.

C.‑Y. Wang et al. 2022. YOLOv7: Trainable bag‑of‑freebies... arXiv:2207.02696.

H. Xu et al. 2021. Edge video analytics for public safety: A survey. ACM Computing Surveys 54, 6, Article 129.

S. Raza, L. Wallgren, and T. Voigt. 2017. Security and privacy for the Internet of Things. In IoT Security.

T. Taleb et al. 2017. Edge cloud and industrial IoT: A review. IEEE Commun. Mag. 55, 4, 64–70.