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Abstract and Figures

Blockchain technology enables the execution of collaborative business processes involving untrusted parties without requiring a central authority. Specifically, a process model comprising tasks performed by multiple parties can be coordinated via smart contracts operating on the blockchain. The consensus mechanism governing the blockchain thereby guarantees that the process model is followed by each party. However, the cost required for blockchain use is highly dependent on the volume of data recorded and the frequency of data updates by smart contracts. This paper proposes an optimized method for executing business processes on top of commodity blockchain technology. Our optimization targets three areas specifically: initialization cost for process instances, task execution cost by means of a space-optimized data structure, and improved runtime components for maximized throughput. The method is empirically compared to a previously proposed baseline by replaying execution logs and measuring resource consumption and throughput.
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{luciano.garcia, marlon.dumas}@ut.ee
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{alex.ponomarev, ingo.weber}@data61.csiro.au
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... Thereby, system states and transitions between these are modeled with a formalized diagrammatic notation. Applications of Petri Nets in the context of blockchain technology include, for example, the formalization of ontologies (e.g., [78]), smart contract simulation and verification (e.g., [277]) and the encoding of business processes for execution engines (e.g., [102]). ...
... Centered on process and workflow models, most publications apply BPMN on the Ethereum blockchain and concern run-time aspects. Especially monitoring and execution are addressed by Weber et al. [263], following optimizations [102], and systems implementing execution such as Caterpillar [41,159,160] and further approaches focused on workflows, e.g., by Sturm et al. [231,232] or based on annotations by Bagozi et al. [20]. For these execution approaches, BPMN is transformed to representations used for execution with a smart contract. ...
... Oftentimes, BPMN is transformed into an intermediate model closer to execution and then used as input for a generator program resulting in one or more smart contracts. The intermediate model has the role of specifying well-defined execution semantics, often relying on Petri Nets such as in [102,163]. ...
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