## 5 Discussion  
The system's initial implementation focuses on the vaccine supply chain, demonstrating its potential benefits in addressing the challenges observed in real-world vaccine supply chains, particularly during the COVID-19 pandemic [38]. However, the system's flexibility allows it to adapt to various supply chain scenarios, including cold-chain logistics for sensitive products like medicines and food. The system's transparency and traceability are key features, enabling end-users, such as patients, to access the complete history of a product using a unique identifier or QR code. This transparent record, stored on a distributed ledger, enhances trust and confidence in the product's authenticity and quality. Moreover, the proposed system addresses trust issues among participating parties in the supply chain by providing a trustless trust mechanism. It ensures timely and accurate  
Figure 21: Truffle config. Figure 22: Contract testnet deployment. payments, reducing potential disputes and enhancing collaboration among parties. The system's transparency also facilitates the early detection of faulty products, preventing them from causing disruptions and additional costs within the supply chain. Despite its potential advantages, implementing this system in real-world supply chains poses challenges due to supply chain operations' complexity, variability, and dynamic nature. Each supply chain may require a customized version of the system, adapted to its specific variables, parties, and sub-flows. Furthermore, not all supply chains require the same level of transparency, and financial considerations, such as batch payments, may differ. Partner selections within supply chains are dynamic, adding further complexity. The implementation of smart contracts in supply chain management varies significantly with territorial application due to differences in technological infrastructure [39], legal environments, and business practices. For instance, in developed countries with advanced IT infrastructure and widespread Internet connectivity, deploying smart contracts for supply chain operations may be relatively straightforward. These countries typically have more robust digital frameworks, which facilitate the quicker integration and acceptance of blockchain technologies. Conversely, in developing nations, challenges such as limited technological penetration and unstable Internet access can hinder the effectiveness of smart contracts. These territories might require additional investments in digital infrastructure and localized training programs to ensure that all participants in the supply chain can engage effectively with the new systems. However, this lack of a robust digital framework can also be beneficial to the implementation of disruptive technologies since the resistance to new technologies will be lower. In fact, the African continent, which includes many developing countries, is a contender in the world for the highest adoption rate of blockchain and cryptocurrencies [40]. Furthermore, the design of smart contracts must be sensitive to local business customs and practices, which can vary widely and may impact the acceptance and successful operation of these contracts. Incorporating an international perspective, the deployment of smart contracts for supply chain management on the Ethereum network must consider regulatory and operational differences across countries. For example, varying legal frameworks concerning digital transactions and data privacy could influence how smart contracts are written and enforced. Countries that are located in the European Union, such as Germany, which has stringent data protection laws under the GDPR (General Data Protection Regulation), may require modifications to smart contract protocols to ensure compliance. Additionally, international trade involves cross-border transactions that might be subject to tariffs and import/export regulations, necessitating smart contracts that can dynamically adapt to these legal complexities.