Blockchain Interoperability: a Feature-based Classification Framework and Challenges Ahead

Abstract

Blockchain is one of the most recent disrupting technologies. Since Bitcoin emerged as its initial application, many blockchain projects arose offering different features for general and domain specific scenarios. In turn, Blockchain platforms were designed as isolated environments where interoperability was not a native feature. During the last years,
academic and industry efforts worked to improve interoperability between blockchain platforms and provided many solutions to solve this problem. However, there is not consensus in the literature on how to classify certain type of solutions and the classification of some of them is not straightforward, which hinders the understanding of the work in the area. In order to organize existing work, this paper provides a feature-based classification framework based on fourteen key interoperability features, that enabled the classification of sixty-two academic papers in three categories and six subcategories. The results show that nowadays research is focused on public interoperability, while private and public-to-private interoperability are still on their first steps. Based on these results, this work also discusses nowadays blockchain interoperability landscape, identifies challenges, and suggests future research directions.