# The Cloud-to-Edge-to-IoT Continuum as an Enabler for Search and Rescue Operations
## 4 Nephele Project as Enabler for SAR Operations
### The Search and Rescue Use Case in NEPHELe  
For the specific use case discussed in this paper, we foresee a service provider which defines the logic of a SAR application to be deployed and executed over the NEPHELE platform. The application logic is represented as an HDA graph which will be available on the NEPHELE HDA repository (see Figure 2). The application logic will define the high-level goal and the key performance indicator (KPI) requirements for the application. To run and deploy the HDA represented by the graph, some input parameters will be given, such as the time, zone, and area to be covered. The application graph will foresee the use of one or more VOs as representative of IoT devices such as robots or sensors and one or more generic functions to support the application (see Figure 3). This latter will support the SAR operations with movement, sensing and mapping capabilities and may be  
Figure 2: NEPHELé’s high-level architecture. Three layers are foreseen: a physical devices layer, with all the IoT devices (e.g., robots, drones, and sensors) connected over a wireless network to the platform; a virtual objects layer at the edge, with the virtual representation of the physical devices as a VO; edge-to-cloud continuum with a set of logic blocks for cloud and networking resource management and the orchestration of the application components. provided through the service mesh approach that enables managed, observable and secure communication across the involved microservices. The VO description required by the SAR HDA graph to be deployed at the edge of the infrastructure will also be available on the NEPHELE repository. In Figure 3, we also see highlighted the different levels of the VOStack and their matching to the SAR application components/microservices. We foresee a service consumer (e.g., a firefighter brigade) owning a set of physical devices (robots, drones and sensors). These devices are ready to be used with some basic software components running and connected to a local network, e.g., a 5G access point. As for the software components already deployed on the robots, we foresee the ROS environment correctly set up, with some basic ROS components already running. The sensors can be either pre-deployed in the area or carried by firefighter personnel. When a SAR mission is started, the Service Consumer connects to the NEPHELE HDA repository and looks for the HDA to deploy and provides the input data that are required. Then, the following operations will have to be initiated by the NEPHELE platform (see Figure 2 for reference of the building blocks):  
1. The synergetic meta-orchestrator (SMO) receives the HDA graph, the set of parameters for the specific instance of the SAR application, the VO descriptors needed for the application and a descriptor of the supportive functions to be deployed in the continuum. The supportive functions are provided by the VOStack and can be, for instance, risk assessments, mission control with task prioritization and optimized planning, health monitoring based on AI and computer vision, predictions of dangerous events, the localization and identification of victims, and so on. The SMO will interact with the federated resources manager and the compute continuum network manager to deploy the networking, computing and storage resource over the continuum according to the requirements derived from the HDA graph, the VO descriptors and the input parameters given by the service consumer;
2. The federated resources manager (FRM) orchestrator will ensure that the application components will be deployed either on the edge or on the cloud based on the computational and storage resources needed for the application components  
Figure 3: VOStack mapping to SAR application scenarios. Hyperdistributed applications are formed of multiple components that are either use-case specific or generic or reconfigurable. These components are placed on different levels of the IoT-to-edge-to-cloud continuum and based on their functionalities are part of the different layers of the VOStack.