Threshold Signature in Off-Chain Components to Manage Inter-chain Transactions

Blockchain is now a widespread technology. However, achieving mass adoption for specific applications requires overcoming several challenges inherent to the use of distributed algorithms and cryptographic primitives, which are central to blockchain technology. One of the main obstacles is interoperability between different blockchains, as each blockchain acts as an isolated environment. To address the interoperability problem, it is essential to use off-chain processes capable of interconnecting the blockchains in question. If the interconnected blockchains are private or consortium-based, attention must be paid to both the confidentiality of the data exchanged and the authority of those authorised to operate on them. We propose a novel approach in which each blockchain implements its own off-chain component. Each off-chain component does not communicate with the others and uses a threshold digital signature scheme as cryptographic proof aimed at improving the control and management of inter-chain transactions, alongside computational complexity reductions.