Enabling Auditing of Smart Contracts Through Process Mining

The auditing sector is acquiring a strong interest in the diffusion of blockchain technologies. Such technologies guarantee the persistence, and authenticity of transactions related to the execution of a contract, and then enable auditing activities. In particular, they make possible to check if observed sequences of transactions are in line with the possibly expected ones. In other words, auditing blockchain transactions allow users to check if the smart contract fits the expectation of the designers, that for instance could check if a given activity is performed or if it satisfies a given set of properties. In such a setting we propose a methodology that exploits process mining techniques to evaluate smart contracts, and to support the work of the auditor. Models resulting from the mining can be used to diagnose if the deployed application works as expected, and possibly to continuously improve them. We illustrate the use of our approach using a small, but real, case study.