ZeKSA: Zero-knowledge Secured Anonymous IoT Resource Sharing on Blockchain

Abstract

IoT devices constitute an important component of Industry 4.0 paradigm, but are greatly hindered by their inherent resource constraints. Resource sharing is therefore an essential operating requirement for these devices but lack of privacy and heavy reliance on centralized architectures pose a serious risk for stable functioning. Use of decentralized and high availability platforms like distributed ledgers can provide divergent and distributed networking conditions but leaves any inter-device interactions completely exposed to third party view. To resolve this, we utilize an innovative combination of smart contracts alongside a zero-knowledge proof generator, known as Tornado Cash, to align IoT devices on a distributed resource exchange platform with privacy guarantees. In concert with public-key cryptography, our solution provides a framework for resource constrained IoT machines to interact through the blockchain for resource exchange purposes with strong privacy guarantees for both devices. Absolute anonymity is ensured by the protocol’s inherent architecture, meaning that participant devices do not reveal any sensitive information and consequently it becomes nontrivial to breach the privacy of either participant. Performance evaluations performed by testing ZeKSA against a competing & comparatively vulnerable protocol yield promising outcomes in terms of blockchain metrics like gas usage & incurred transaction costs.