## 3 Blockchain Technologies for Maritime Applications/Use Cases
### Blockchain for Other Applications in Maritime Ecosystem: Maritime Blockchain Labs (MBL)  
The maritime shipping ecosystem is complex and varies significantly across different countries. Figure 7 shows the various elements of the maritime ecosystem. Due to the diverse interconnections among companies, nations, and environmental factors, defining a  
Figure 6: TradeLens Achievement Numbers (re-created with numbers from [61]).  
single, uniform ecosystem is challenging. Each stakeholder within this ecosystem fulfills a distinct role, which is heavily influenced by surrounding factors. Furthermore, stakeholders often take on multiple roles depending on the circumstances. The key components of the maritime ecosystem include policymakers, regulators, ports, shippers and shipping agents, ship owners and operators, shipbuilders, fuel providers, researchers, etc. These entities all play crucial roles--each of them contributes to the overall functionality and resilience of the maritime industry [69].  
Maritime Blockchain Labs (MBL) [70] was established to address challenges within the maritime shipping ecosystem by integrating blockchain technology. MBL focuses on enhancing efficiency, regulatory compliance, and safety management in the maritime industry through the development and testing of blockchain-based solutions. MBL collaborates with a wide range of stakeholders, including ship owners, operators, and regulatory bodies, to create blockchain solutions that can be broadly implemented across the industry. Currently, MBL pilot projects are being conducted in three areas: the Marine Fuels Assurance Pilot, the Crew Certificate Management Pilot, and the Misdeclaration of Dangerous Goods Pilot.  
The Marine Fuels Assurance Pilot focuses on ensuring the quality of marine fuel from the terminal to the vessel using blockchain technology. To achieve this, the MBL project developed a blockchain-based digital bunker delivery note specifically designed for the marine fuel supply chain. This tool allows stakeholders to enter and review details of fuel transactions and transfers between terminals, bunker barges, and receiving vessels. By enabling intuitive access to fuel-related information, the project enhanced the reliability of marine fuel quality. The Crew Certificate Management Pilot aims to create a blockchain platform that verifies the identity, training records, and certificate issuance, management, and clearance processes of all crew members. By collecting and reorganizing information according to the diverse requirements of various countries and companies, this platform offers a secure and trustworthy solution for certifying seafarers, significantly simplifying the previously complex verification process. The Misdeclaration of Dangerous Goods Pilot evaluates how blockchain technology can support the proper documentation and declaration of dangerous goods. This project standardized the inputs and outputs required  
Figure 7: Maritime Shipping Ecosystem (re-created with inspiration from [69]).  
for the safe end-to-end delivery of hazardous materials, thereby building trust in the custody chain. By leveraging blockchain, the project enabled the immediate handling of quality assurance inspections and data extraction at each stage without the need for traditional documentation. This prototype ultimately improved the safety of hazardous material transportation, reducing the risk of maritime accidents [71].  
However, MBL is facing challenges in collaboration with other consortium members, a persistent issue in every maritime blockchain project. Members of the blockchain consortium are often reluctant to share information on platform [70]. Despite these challenges, MBL remains significant in advancing the maritime ecosystem by offering a variety of services to the maritime industry through blockchain technology. MBL's innovative approach holds key importance in leading the efficiency and sustainability of the maritime industry.