Blockchain-based traceability of the wine supply chain

Abstract

Supply chain systems, organisations which handle the flow and transformation of goods, have been around since the inception of commercialization. Through time, the management of these chains has been an increasing focus for companies to get the needed information to help maintain and improve the performance of workers and the efficiency of production. Additionally, via analysis and tweaks on the supply chain, a goal of supply chain management is for the system to be modified to have more transparent, flexible, and robust properties. In this project, the managerial process in the industry of wine distribution is taken into account. Problems that still arise from this industry added to those found in regular supply chains include examples such as the fraudulency of wine. Thus properties of the problems in the system which were required to be addressed were the concentration of authority and the traceability of the commodities. The objectives of this project are to explore the design options of this supply chain management in a smart contract view and identify properties that can be formally verified. The design of how the wine distribution supply chain operates was taught through the use of other papers that dealt with the same industry. The entities and their relationship with other entities were defined. The phases of the wine supply chain are split into the vineyard, which produces the grapes, the manufacturer, which handles the winemaking process, and finally, the market, which distributes from the winemakers to the public. The flow and transformation of the items are considered through all the entities from the vignerons to the consumers. Blockchain technology makes use of a digital distributed ledger of transactions accessible by shared nodes on a network in a peer-to-peer and decentralized manner. The transactions are immutable, secure, and trusted. With the use of smart contracts, self-executing programs given a set of requirements run functionalities which can include transferring monetary values from one address to another, the implementation of the wine supply chain system is built. The smart contracts in this project are under the Ethereum platform using the Solidity language. The inclusion of the technologies mentioned help overcome the downfalls of centralised systems, reduce points in the system with heavy trust as well as having a system with more transparency and traceability included. A type of formal verification, an evaluation process where specifications are checked if they satisfy well-formed requirements, and expected properties are upheld, which is called runtime verification. Runtime verification is the testing of properties whilst the system is still executing. In this scenario, the properties are defined by the expected behaviour of the smart contract. Proving the behaviour shows that the smart contract satisfies the intended goals. The tool of Contract- Larva is used to generate an updated safe smart contract by providing the initial smart contract and the properties of the smart contract, which are expressed in Dynamic Event Automata. Through comparing the gas cost to execute the initial smart contract with the modified one, it is determined which runtime verification tests are important enough to still be included in the system.