Adapting Workflow Management Systems to BFT Blockchains – The YAWL Example

Blockchain technology provides an auditable and tamper-proof distributed infrastructure that can support distributed workflow management. Blockchains based on a Byzantine Fault Tolerance (BFT) ordering consensus protocol address many of the shortcomings of proof-of-work chains, such as latency and non-finality of consensus. They are a suitable technology to support workflow execution, in large part because applications do not need to be adapted to deal with eventual consistency and delayed consensus of proof-of-work blockchains. Moreover, in contrast to earlier work that has typically developed custom workflow engines using smart contracts, we port an existing, full-featured workflow engine, the YAWL workflow engine, to a blockchain-based workflow management system (WfMS) without smart contracts.