Blockchain interoperability: the state of heterogenous blockchain‐to‐blockchain communication

Abstract

Blockchain technology has been increasingly adopted over the past few years since the introduction of Bitcoin, with several blockchain architectures and solutions being proposed. Most proposed solutions have been developed in isolation, without a standard protocol or cryptographic structure to work with. This has led to the problem of interoperability, where solutions running on different blockchain platforms are unable to communicate, limiting the scope of use. With blockchains being adopted in a variety of fields such as the Internet of Things, it is expected that the problem of interoperability if not addressed quickly, will stifle technology advancement. This paper presents the current state of interoperability solutions proposed for heterogenous blockchain systems. A look is taken at interoperability solutions, not only for cryptocurrencies, but also for general data‐based use cases. Current open issues in heterogenous blockchain interoperability are presented. Additionally, some possible research directions are presented to enhance and to extend the existing blockchain interoperability solutions. It was discovered that though there are a number of proposed solutions in literature, few have seen real‐world implementation. The lack of blockchain‐specific standards has slowed the progress of interoperability. It was also realized that most of the proposed solutions are developed targeting cryptocurrency‐based applications.

A Blockchain Oracle Interoperability Technique for Permissioned Blockchain

“…In this section we compare the Oracle-based interoperability method with the interoperability solutions described in the "Related work" section. The comparison is done using 6 features identified in a recent survey paper [5] to assess interoperability solutions for blockchain systems. We added a seventh feature, "Performance Evaluation", since it is essential to measure the technique's performance to ensure acceptable performance of the system and identify weaknesses and possible bottlenecks.…”

“…Interoperation between blockchain networks, whether homogeneous or heterogeneous, soon became an area of interest to many researchers in both academia and industry [5]. Techniques for achieving interoperation and supporting cross-network transactions varied based on the purpose of the interoperation and the type of blockchain network supported.…”

“…Consequently, diverse interoperability solutions have been developed to address the need for blockchain-based systems to communicate and expand the capabilities of blockchain systems. The majority of the developed techniques were designed to allow asset transfer and exchange between different blockchain platforms, mostly supporting public blockchains and had the disadvantage of increased transaction costs [5]. When it comes to arbitrary data exchange among private blockchain networks, there is noticeable lack in the interoperability techniques designed specifically to allow private blockchain networks perform cross-network transactions and exchange data.…”

ChainKeeper: A cross‐chain scheme for governing the chain by chain

“…In recent years, there have been many studies on cross‐chain interoperability. According to their use, they are divided into cross‐chain schemes for cryptocurrency transfer and cross‐chain schemes for data sharing [13].…”

Cross‐blockchain decentralized asset transfer protocol for public blockchains

“…Harris 14 has discussed decentralized exchanges and cross‐chain bridge solutions along with recent hacks targeting cross‐chain bridges. Kotey et al 15 have performed a systematic literature review of heterogeneous blockchain interoperability solutions. They have discussed 25 interoperability solutions along with their shortcomings and compared them based on their characteristics.…”