Optimizing Systemic Redundancy of Traffic Sensor Networks While Maintaining Resilience: New Evidence From Using Graph Learning

Abstract

The optimization of systemic redundancy by minimizing the sensor quantity can improve the efficiency of sensor networks and save costs. However, from the perspective of risk management, this redundancy reduction can also bring a significant loss in the overall network resilience because the less the systemic redundancy is, the fewer backup components in the network when shocks hit and, therefore, the less overall resilience. In this paper, we investigate this intractable dilemma and attempt to pinpoint the tradeoff point for a city-scale automatic number plate recognition (ANPR) system in Cambridge, UK. By developing a two-stage graph deep learning (GDL) model, we first optimize the layout of the ANPR system to reduce redundancy and find its efficiency profile. Next, we study what effects this redundancy reduction can bring to the overall resilience, as the overall observability drops with the reduction in the number of sensors and find an optimal balance. The results show that our approach can effectively optimize the system's redundancy by using only 47% of the original sensors to reconstruct the full picture with a mean absolute error (MAE) of only 11.18 and a root mean square error (RMSE) of 19.49; most importantly, the overall system resilience is maintained at 70% in the meantime. This paper provides an alternative perspective for dealing with the well-known 'efficiency-resilience' dilemma and offers new evidence to enable better decision and policy making for city managers and planners in local authorities.

The New Label Bit Repair Fast Reroute Mechanism

“…Detection and diagnosis of outages: Research work seeks to improve methods and tools for the detection and diagnosis of network outages, which is important for rapid repair and restoration of connectivity [16]- [18]. Backup and redundancy are looking for solutions so that in the event of a device or line failure, traffic is automatically redirected to backup devices [19], [20]. In current IP networks, the biggest problems occur in the form of -stability, availability, and performance, and the aforementioned areas are devoted to how to achieve higher stability, availability, and performance in modern IP networks, which is key to the effective functioning of current ICT.…”