Blockchain interoperability is emerging as one of the crucial features of blockchain technology, but the knowledge necessary for achieving it is fragmented. This fact makes it challenging for academics and the industry to seamlessly achieve interoperability among blockchains. Given the novelty and potential of this new domain, we conduct a literature review on blockchain interoperability, by collecting 262 papers, and 70 grey literature documents, constituting a corpus of 332 documents. From those 332 documents, we systematically analyzed and discussed 80 documents, including both peer-reviewed papers and grey literature. Our review classifies studies in three categories: Cryptocurrency-directed interoperability approaches, Blockchain Engines, and Blockchain Connectors. Each category is further divided into sub-categories based on defined criteria. We discuss not only studies within each category and subcategory but also across categories, providing a holistic overview of blockchain interoperability, paving the way for systematic research in this domain. Our findings show that blockchain interoperability has a much broader spectrum than cryptocurrencies. The present survey leverages an interesting approach: we systematically contacted the authors of grey literature papers and industry solutions to obtain an updated view of their work. Finally, this paper discusses supporting technologies, standards, use cases, open challenges, and provides several future research directions.
翻译:链链互操作性正在成为链链技术的关键特征之一,但实现这一技术所需的知识却支离破碎。这一事实使学术界和工业界难以无缝地实现链链之间的互操作性。鉴于这一新领域的新颖性和潜力,我们通过收集262份论文和70份灰色文献文件,对链链互操作性进行文献审查,这构成了一整套332份文件。从这332份文件中,我们系统地分析和讨论了80份文件,包括同行审查文件和灰色文献。我们的审查将研究分为三类:加密货币直接互操作性方法、链链引擎和链连通器。每个类别进一步分为基于确定标准的亚类。我们不仅讨论每个类别和亚类的研究,而且讨论跨类的研究,全面概述链互操作性,为这一领域系统研究铺平了道路。我们的调查结果显示,链互操作性的范围比加密的公开性要广得多。本次调查利用了一种有趣的方法:我们系统地联系了灰色文献的作者和行业解决办法的作者,以获得最新版本的指南。我们不仅讨论了各个类别和亚类的研究,而且还讨论了各种研究方向。