## 5 The COGNIFOG Project
### Use Cases
#### 5.4.1 Trial 1--Disaster Management in Urban Centers  
Centennial floods, which occur, on average, once every hundred years, can cause significant disruption to urban infrastructure such as those found in most major cities. These extreme events are often used for planning purposes as they overwhelm transportation, communication systems, and emergency services, making roads and railways impassable and isolating communities. Damaged communication networks further hinder emergency responses, underscoring the need for more resilient infrastructure and effective flood management strategies. Of late, these types of 'once-in-a-lifetime' floods are becoming increasingly frequent and so the need to ensure adequate planning is increasing. Our first real-world deployment is designed to test COGNIFOG in the city of Paris, focusing on planning for a centennial flood event. This trial is managed by the Thales group in collaboration with city partners. In flood emergencies, timely intervention by authorities is crucial, requiring effective synchronization between rescue teams. Current systems, however, face challenges due to the limitations of existing architecture, which is not designed to handle critical factors like network congestion, latency, and the automatic re-provisioning of applications during disruptions. This reliance on standard scheduling policies, such as CPU and RAM usage, leaves the system vulnerable during connectivity failures. Edge computing without intelligent workload placement exacerbates these issues, leading to inefficient resource use, higher latency, increased power consumption, and network congestion. The lack of dynamic adaptability in workload distribution reduces scalability, system reliability, and real-time processing capabilities. In flood scenarios, this inefficiency impacts low-latency applications, making the system more costly, less effective, and prone to failure. The requirements that a collaborative mission use case imposes on the COGNIFOG platform emphasize deployment automation across edge and far-edge environments to ensure consistency, scalability, and security. This enables organisations like rescue centres to swiftly deploy software and applications, responding more effectively to changing needs. Rapid infrastructure and device provisioning are essential during disasters, supporting real-time situational awareness. Fast cloud application deployments reduce downtime, enhance scalability, and improve cost efficiency. Time predictability and resiliency to hardware or connectivity failures ensure operational stability and continuity during emergencies. Additionally, energy consumption monitoring is important for reliability and sustainability, while single-touch orchestration allows seamless deployment and management of applications with minimal effort. Considering these requirements, the primary challenge in this use case is managing data stream processing chains with a diverse array of devices and computing resources. These environments impose stringent constraints on both energy efficiency and processing time. Effective management is crucial because, in such missions, every minute counts. Ensuring that the system operates efficiently under these demanding conditions requires careful coordination and optimisation of resources. This involves maintaining high performance and reliability and minimizing energy consumption to meet the rigorous operational standards necessary for mission-critical applications. In addition, in a rescue mission, many actors and pieces of equipment, such as vehicles and intervention forces on the ground, are mobile. This not only complicates the network but also imposes significant constraints on the dynamism of the application infrastructure. Returning to our key benefits table (Section 4.1), this use case has been designed to focus on three key aspects of the CEI continuum, i.e., improved reliability and operational continuity, enhanced scalability, and improved performance and responsiveness.