Xiongfei Zhao

Xiongfei Zhao, Yain-Whar Si

Nowadays, academic certificates are still widely issued in paper format. Traditional certificate verification is a lengthy, manually intensive, and sometimes expensive process. In this paper, we propose a novel NFT-based certificate framework called NFTCert, which enables the establishment of links between a legitimate certificate and its owner through a Blockchain. In this paper, we describe the implementation of the NFTCert framework, including schema definition, minting, verification, and revocation of NFT-based certificates. We also introduce a payment gateway into the minting process, which enables NFTCert to be used by a wider audience. Therefore, participants of NFTCerts do not need to rely on cryptocurrency for transactions. All in all, the proposed framework is designed to achieve usability, authenticity, confidentiality, transparency, and availability properties when it is compared to existing Blockchain-based systems.

Xiongfei Zhao, Yain-Whar Si

As the core technology behind Bitcoin, Blockchain's decentralized, tamper-proof, and traceable features make it the preferred platform for organizational innovation. In current Bitcoin, block reward is halved every four years, and transaction fees are expected to become the majority of miner revenues around 2140. When transaction fee dominates mining rewards, strategic deviations such as Selfish Mining, Undercutting, and Mining Gap could threaten the integrity and security of the Blockchain. This paper proposes a set of Dynamic Transaction Storage (DTS) strategies for maintaining a sustainable Blockchain under the transaction-fee regime. We demonstrate that block incentive volatility can be reduced through systematic simulation by applying DTS strategies and avoiding strategic deviations. With DTS, public Blockchains such as Bitcoin become sustainable when the mining reward is solely based on the transaction fee.