Secure Data Provenance in Cloud-centric Internet of Things via Blockchain Smart Contracts

Mission-critical applications such as industrial control, smart grids, security and surveillance systems are highly dependent on cloud-centric IoT networks. In such networks, the diverse IoT devices harvest the data from the remote environments and relay it to multiple intermediate agents over the wireless links towards the cloud for storage, analysis and decision making. Such systems require highly trustworthy data to guarantee accurate and timely decisions. However, in most of the cases, the IoT data becomes dubious during the transmission towards the cloud. Ensuring data provenance in such a heterogeneous multi-layered system is a critical security issue. Therefore, in this paper, we propose a secure data provenance framework for cloud-centric IoT network by utilizing the immutable, deterministic and public nature of the blockchain smart contracts with the traditional cloud infrastructure. In the framework, the cryptographic hash of the device metadata is stored in the blockchain whereas actual data is stored off-chain i.e., in the cloud, making it highly scalable for a dense deployment of IoT devices in the network. Multiple smart contracts are stationed in the blockchain to guarantee the provenance receipt to the data stored in the cloud. The initial evaluation revealed that the proposed framework is highly acceptable in achieving the data provenance for large-scale cloud-centric IoT networks.