Scarce and niche in the literature just a few years ago, the blockchain topic is now the main subject in conference papers and books. However, the hype generated by the technology and its potential implications for real-world applications is flawed by many misconceptions about how it works and how it is implemented, creating faulty thinking or overly optimistic expectations. Too often, characteristics such as immutability, transparency, and censorship resistance, which mainly belong to the bitcoin blockchain, are sought in regular blockchains, whose potential is barely comparable. Furthermore, critical aspects such as oracles and their role in smart contracts receive few literature contributions, leaving results and theoretical implications highly questionable. This literature review of the latest papers in the field aims to give clarity to the blockchain oracle problem by discussing its effects in some of the most promising real-world applications. The analysis supports the view that the more trusted a system is, the less the oracle problem impacts.

Decentralized Finance (DeFi) takes the promise of blockchain a step further and aims to transform traditional financial products into trustless and transparent protocols that run without involving intermediaries. Similar to how 2017 was the year of ICOs, 2020 was the year of DeFi, with more than fifteen billion dollars of total investments. The decentralized platforms utilize oracles to retrieve asset data from the external world, but their choice and management criteria are often unknown to the end-users. If oracles are poorly selected or managed, the funds of a rising number of investors are inevitably in danger. The issue, known as “the oracle problem”, which makes real-world applications controversial and debated due to the loss of decentralization, had recently drawn attention to DeFi, given the crescent number of related hacks that caused the loss of millions of dollars held in DeFi projects. Through a multivocal approach that considers academic papers, whitepapers, preprints, and opinion posts, this study aims to shed light on the pattern that identifies the oracle problem in DeFi and outline the most promising ways to overcome the related weaknesses. This research supports the view that the oracle problem in decentralized finance bears specific characteristics which require standardization and appropriate economic incentives to be addressed.

Purpose: This paper aims to examine and overcome the barriers to the widespread adoption of blockchain technology, introducing a novel concept of sustainability in the fashion supply chain.Design/methodology/approach: This work is an exploratory study of a well-known fashion company operating in the Veneto region (Italy). Data extracted from interviews and focus groups are coded using the (CAQDAS) software AQUAD. The outcome is then organized according to an adapted TOE view.Findings: This exploration study's findings support the idea that the blockchain solution could be a valuable add-on in sustainable supply chains. However, a high understanding of technology and extensive communication with clients is required for successful integration.Research limitations/implications: Being the outcome of qualitative analysis, the findings require further investigation to be inferable at a broader scale. As the project is still incomplete, some managerial choices are always subject to change.Practical implications: Focused on a practitioner approach, this paper should guide managers in the process of successfully implementing blockchain technology. Arguably, similar companies may opt for similar choices.Originality/value: To the best of the authors' knowledge, this is the first paper to contextualize and address the blockchain adoption barriers in the fashion supply chain. Furthermore, it offers an overview of how blockchain affects sustainable production.

Much of the excitement around blockchain is mainly due to promising applications in the financial sector. However, many also believe in the technology’s potential to disrupt non-financial sectors and applications, including supply chains, energy, e-voting, healthcare, and education. The application of blockchain within the education sector is expected to make improvements to academic transcripts, credentials, digital libraries, and student records. Research in this domain is rapidly increasing, and current reviews summarize the proposed improvements. On the other hand, the analysis undertaken has remained at a general level that lacks the depth required to cover diverging proposals that have emerged. This review focuses on the application of blockchain for academic transcripts. The aim is to find, among the proposed models, converging aspects that resolve common challenges and may lead to a universally accepted de-facto standard. Furthermore, since academic institutions will serve as oracles to the particular blockchain applications, a discussion on their trustworthiness will be outlined to explore if the proposed applications efficiently address the oracle problem. The outcome of this review highlights the need for a standardized approach built on a public blockchain to promote faster adoption and acceptance. Furthermore, oracles should be incentivized in order for the system to be sustainable, while their identities and activities should be known and identifiable.

Blockchain implications within the sustainability domain are rapidly arousing the interest of researchers and institutions. However, despite the avalanche of articles, papers, and recently published books, innovation in the blockchain domain is still heavily influenced by light literature, such as news, articles, opinion posts, and white papers. Lacking a homogeneous literature background, case studies often fall into storytelling, providing mere descriptions of the facts according to the writers’ impressions and opinions. We therefore investigate blockchain adoption for sustainable purposes through a case study while remaining firmly grounded in three main theoretical literature streams: knowledge management, knowledge infrastructure, and trust. Since blockchain interaction with the real world is managed by oracles, addressing the oracle problem is essential in order to evaluate the effectiveness of blockchain for sustainability issues. However, to the best of the authors’ knowledge, no other paper has efficiently addressed this subject or even mentioned it. Recognizing its scarce consideration in the literature, the oracle problem will be analyzed in both theoretical and practical terms, thereby providing a way to solve the issues related to non-fungible products in the supply chain. Choice over the selected case study was made in light of the divergence in motives for the adoption of blockchain (economic over social), which makes the results more inferable at a broader scale and offers an insight into how sustainable innovations can also be economically viable.

Whereas the use of distributed ledger technologies has previously been limited to cryptocurrencies, other sectors—such as healthcare, supply chain, and finance—can now benefit from them because of bitcoin scripts and smart contracts. However, these applications rely on oracles to fetch data from the real world, which cannot reproduce the trustless environment provided by blockchain networks. Despite their crucial role, academic research on blockchain oracles is still in its infancy, with few contributions and a heterogeneous approach. This study undertakes a bibliometric analysis by highlighting institutions and authors that are actively contributing to the oracle literature. Investigating blockchain oracle research state of the art, research themes, research directions, and converging studies will also be highlighted to discuss, on the one hand, current advancements in the field and, on the other hand, areas that require more investigation. The results also show that although worldwide collaboration is still lacking, various authors and institutions have been working in similar directions.