Decentralised and Collaborative Auditing of Workflows

Abstract

Workflows involve actions and decision making at the level of each participant. Trusted generation, collection and storage of evidence is fundamental for these systems to assert accountability in case of disputes. Ensuring the security of audit systems requires reliable protection of evidence in order to cope with its confidentiality, its integrity at generation and storage phases, as well as its availability. Collusion with an audit authority is a threat that can affect all these security aspects, and there is room for improvement in existent approaches that target this problem. This work presents an approach for workflow auditing which targets security challenges of collusion-related threats, covers different trust and confidentiality requirements, and offers flexible levels of scrutiny for reported events. It relies on participants verifying each other's reported audit data, and introduces a secure mechanism to share encrypted audit trails with participants while protecting their confidentiality. We discuss the adequacy of our audit approach to produce reliable evidence despite possible collusion to destroy, tamper with, or hide evidence.

Towards Blockchain-Based Auditing of Data Exchanges

“…If no companies admit the error, and all parties produce their own internal records showing no fault, one can only assume some of them intentionally modified the existing records in their system to prevent truthful auditing. Having a robust audit system with immutable audit trail is vital to assure non-repudiation and assign accountability for malpractice [2]. Blockchain is a decentralized distributed ledger that contains an ordered list of records in a chain [3].…”