Abstract
Blockchain is a distributed ledger technology (DLT) to manage data in a
decentralised way. During the last years, interoperability has become
one of the main challenges within blockchain research as blockchains
increasingly require integration between each other. Indeed, blockchains
work by design in silos of information as interoperability is not a
native feature. The main efforts in the field are focused on
blockchains, such as Bitcoin and Ethereum. However, interoperability in
DLT remains as an almost untouched area of work as they introduce
additional requirements focusing on privacy and identity. Although there
are some interoperability solutions for DLT, they are either high-level
design proposals not providing concrete implementations or focus on
interoperability issues between business applications and blockchain
platforms. In this paper we propose a gateway-based platform-to-platform
interoperability solution for DLT, which comprises a detailed solution
design and a reference implementation. The proposal was assessed through
the development of a social security case scenario and the evaluation
through two interoperability frameworks. A reference implementation was
built using two DLT: Hyperledger Fabric and Corda. The experimental
results shows that it is possible to achieve technical interoperability
between two heterogeneous DLT platforms using a gateway-based
interoperability solution, relaxing decentralisation, data privacy,
identity and authorisation management properties.