Assessing interoperability solutions for distributed ledgers

Abstract Distributed ledgers (DLs), including blockchains, are gradually becoming an accepted technology. Almost all of these DLs are currently siloed and there is an increasing need for interaction. To fulfill this need, interoperability solutions have been proposed. However, DL interoperability has been scarcely researched and it is not always clear which properties these solutions have, nor which particular issues exist in such solutions. This paper describes a set of key properties with which interoperability solutions can be evaluated. Using these key properties, we systematically compare the two most common solutions and identify several issues, some of which cannot be solved by the solutions themselves. Finally, these properties can be used in practice to assess and compare interoperability solutions, and can be used to determine which kind of solution fits best.