Inter Blockchain Communication

Blockchain technology is growing massively where the number of blockchain platforms and decentralized applications are increasing rapidly in the last years. However, most of the existing blockchain networks are operating in a standalone environment isolated from each other, which increases scalability and connectivity issues in the current blockchain platforms as well as limiting the blockchain adoption in industry ecosystems. In the current phase, different blockchain networks don't have mutual trust where they cannot interact with each other and their capacity level has only reached a level similar to LAN. Due to the high barriers between the independent isolated blockchain platforms, researchers have started to focus on the concept of Blockchain interoperability. Blockchain interoperability is the ability of connecting multiple blockchain networks together, which significantly increases and solves scalability and connectivity issues in the blockchain platforms. Given the potential of blockchain interoperability and cross blockchain communication, many researchers are working on finding the optimal cross blockchain communication solution. As blockchain interoperability is emerging as an essential blockchain feature, the number of proposed blockchain interoperability solutions have been increasing within the last few years. In this paper, a survey of all the available cross blockchain communication solutions are discussed with a comparison of the proposed architectures.