# Edge Computing Architecture for the Management of Underwater Cultural Heritage
## 2 Related Work
Although LoRa is recognised for its long-range communication capabilities, reaching distances of approximately 10 km in direct line of sight, many maritime points of interest are located far beyond this range [34]. The lack of repeaters and gateway stations to extend the coverage over such vast distances significantly limits its ability to connect remote IoT systems to the global internet. As a result, LoRa is not a viable option for establishing real-time, large-scale data transmission from remote areas to cloud-based services or centralised networks. However, LoRa can still be effectively employed for localised communication between surface nodes within its operational range. In rural environments, where there are fewer obstacles, the range can be extended up to 35 km using the narrowband internet of things (NB-IoT) technology. The signal strength in open areas allows the NB-IoT to achieve greater coverage, making it well suited for remote or sparsely populated regions, such as ocean environments [35]. Significant advancements in satellite communication technologies have addressed this limitation in the past decade, particularly with low Earth orbit (LEO) satellites. Companies such as Telesat, OneWeb, SpaceX, and Amazon have developed LEO satellite constellations that offer near-global broadband coverage, significantly enhancing connectivity for remote IoT systems [36]. NTNs, including satellites, drones, and high-altitude platforms, are emerging as robust solutions for integrating IoT networks with space-air-sea systems, enabling seamless data transfer and the real-time monitoring of maritime environments [37]. Integrating the IoT with NTNs has proven to be particularly transformative in fields such as maritime surveillance, environmental monitoring, and disaster response, where real-time data from remote sensors are essential [38]. This convergence of the IoT and NTNs is paving the way for more resilient and efficient marine IoT applications. Web-based platforms provide a comprehensive solution for conserving UCH. These platforms enable centralised storage and remote access to large UCH datasets from any location. Field data, including images, videos, and environmental parameters, can be uploaded in real time to the cloud, allowing for seamless access and processing. Cloud technology also facilitates photogrammetry and 3D modelling, which can be performed remotely, eliminating the need for specialised hardware and software during field surveys. Notable examples in the literature showcase the effectiveness of these platforms. For instance, the Lab4 Dive system [6] is an innovative product designed for surveying, documenting, and preserving UCH in the Mediterranean Sea. This system comprises an underwater tablet to assist divers, a docking station that acquires and exchanges data from various environmental sensors and a high-resolution camera, and a remote server hosting the cloud database and performing 3D reconstruction using photos captured during the survey. Another notable platform is VIRTUALDiver [7], which leverages virtual reality (VR) and augmented reality (AR) technologies to design and manage interactive tourism experiences. In the Republic of Mauritius, UCH data are uploaded to an online platform called the E-platform, which stores a wide range of information, including archaeological articles, legislation, reports, field data, and remote services [39]. The MACHU project utilises the MACHU GIS system [40] as its central online platform, which is a web-based application integrating essential information for managing UCH, such as heritage details, environmental data, legislation, and historical maps. Innovative architectures, such as satellite edge computing, enhance data processing efficiency, enabling faster response times and reducing bandwidth usage through localised computing [41]. Edge computing significantly reduces latency by offloading resource-intensive tasks to nearby nodes, optimising resource use, and improving user experience.