# Integrating the IoT and Blockchain Technology for the Next Generation of Mining Inspection Systems
## 2 Related Works  
Mining activities that embrace the digital transformation will increase production, run more efficiently and effectively, and be more environmentally sustainable. In addition, they have the potential of setting new standards for workers' health and safety and contribute to reskilling through educational and training programs. As an example, the Syama mine is a site in Mali that is benefitting from digitalization [7]. Resolute Mining took over operations at Syama in 2015, transforming it into the world's first purpose-built automated mine. Employees use a fiber-optic network connected to aboveground control centers to manage and monitor all activities, from clearing the drill point to extraction, loading, and hauling. Another advance at Syama is Sandvik Automine for Trucks, officially released in December 2019, allowing the haul trucks to run autonomously underground using LiDAR and then switch to GPS when they reach the surface. Although the initial investment was steep, machines can now operate 22 h a day without time lost due to shift changes. Overall, the effects of digitization will cut mining costs by 30%, representing a true game-changer within the mining sector, especially for remote regions [8]. Currently, an increasing number of studies aim to cover the monitoring of machine or equipment parameters [9; 10] with online and offline processing to detect or predict future failures, the definition of risk-assessment algorithms [11] to estimate the risk associated with different aspects to the mines (e.g., cyberattacks to mining equipment [12], workers' safety [13], machine faults [14], etc. ), operation monitoring [15], and so on. Along this line, [PERSON] et al. introduced the term Mining 4.0 [16] as the declination of the Industry 4.0 concept in the mining domain. Similarly, [PERSON] et al. [17] proposed and discussed a novel technique to plan the movement of shovels and trucks by adopting a digitized approach. Regarding the maintenance of assets, [PERSON] et al. [10] used unmanned aerial vehicles (UAVs, i.e., drones) to inspect rollers in conveyor belts and detect possible failures using computer vision techniques. In recent years, there has been a growing interest in integrating blockchain technologies into IT systems for enabling trustless architectures [18] in several application domains. Blockchain provides a trusted repository of information, where data are secure and traceable, and the data source can be precisely identified [6]. Thus, blockchain has the potential to enhance data security, traceability, accountability, integrity, transparency, and trustworthiness [19]. One of the first domains adopting blockchain-based systems with enthusiasm was insurance. According to authors of [20], blockchain could positively affect different processes, such as improving the customer experience and reducing operating costs. In this case, the cryptography primitives of blockchain could reduce the overhead related to manual data entry and verification. Despite the focus, these benefits also apply to several other application domains. For instance, authors of [19] explored the potential of blockchain in the automotive industry [19] for identity management and tamper-proof data management. Likewise, authors of [21] discussed the benefits of blockchain in the oil and gas industry for tracking, compliance, and data storage. Recently, authors of [22] discussed the use of blockchain technology to improve built asset sustainability through a comprehensive and detailed material traceability method. More related to our work, authors of [23] presented a blockchain-based system to store aircraft maintenance records, with a focus on security. Similarly, authors of [24] presented a blockchain-based framework for the maintenance of military equipment. Together, these studies provide important insights into the potential of blockchain networks to enable trust among unknown stakeholders by providing a transparent record of information in a decentralized way, removing the need for a trusted intermediary.