The growth in the number of blockchain platforms is booming. That is a good thing. Looking beyond a “one size fits all” platform sparks new possibilities and may lead to platform innovations we have yet to imagine. But the ecosystems developing around platforms must also interact for blockchain to achieve its full potential.
With the future state of interoperability as an end goal, last year Accenture announced that we developed and tested two solutions that allow two or more blockchain enabled ecosystems to integrate. Since then, we developed a new solution specifically created for permissioned blockchains that works without a central connector node. I am happy to announce that we open sourced this new solution as Blockchain Integration Framework, a Hyperledger Lab.
Blockchain Integration Framework defines a communication model that lets permissioned blockchain ecosystems exchange any on-chain data or custom assets, independent of the platform. Specifically, it introduces an “interoperability validator” overlay network for each of the blockchain networks for which you want to exchange assets. Interoperability validators are known or broadly discoverable by the ecosystem and typically participants already taking part in the governance or consensus.
Interoperability validators will collectively handle export requests from local nodes by verifying against their version of the ledger (steps 1 to 3). Each request is answered by a (configurable) minimum quorum of validator signatures (steps 4 and 5). The network can continue working even if some validators are down or not participating, assuming the minimum quorum can be guaranteed. Any secure off-chain communication system can deliver messages certified by a distributed ledger’s transfer validators (step 6). A proof coming from a foreign distributed ledger can be verified against the public keys of the transfer validators of that foreign distributed ledger either locally by the recipient or using on-chain logic – typically smart-contracts (step 7 and 8).
This tutorial demonstrates how to transfer a simple asset between a Hyperledger Fabric and a Quorum network. If you have a favorite DLT network, please consider contributing a connector. We encourage you to have a look at the source code and welcome any contributions no matter the size. Please reach out on the #blockchain-integration-framework chat channel with any questions.