Fair blockchain-based delivery of digital assets

Online transactions are becoming increasingly popular, and the purchase and delivery of digital assets is a prominent example. In these transactions, buyers are hesitant to pay for an asset until they receive it, whereas sellers are reluctant to send the asset until they are paid. Unfortunately, actual solutions do not always meet all the requirements to conduct a secure exchange, with fairness being one of the requirements that needs more attention. Historically, solutions to this problem have relied on trusted third parties (TTPs) serving as trusted intermediaries among participants, but the advent of blockchain has enabled the reduction or elimination of TTP involvement in many cases. In this paper, we present a fair blockchain-based solution that does not require any TTP for the secure delivery of digital assets, proving its technical feasibility and cost-effectiveness through assessments on blockchains based on the Ethereum Virtual Machine.