A Method for Resolving Blockchain State Conflicts in IoT—Using Customized Smart Contract Variables

Smart contracts are essential tools for enabling interaction between blockchain and Internet of Things (IoT) systems. For example, in cold chain logistics, the blockchain can obtain the states of the logistics system through smart contracts. However, direct interactions between smart contracts and these systems introduce uncertainties, potentially leading to network forks or state inconsistencies, which can compromise the security and reliability of the blockchain. To address these challenges, a novel smart contract variable, ExState, is proposed, specifically designed to track and store the dynamic states of IoT systems. Additionally, a corresponding operational logic is defined to organize these states into sequential records, ensuring that the state sequences obtained by each node remain consistent, effectively mitigating state conflicts. In addition, a formal model is developed, accompanied by a theoretical analysis of its determinacy. Experimental results demonstrate that, in cross-chain scenarios, this method achieves a performance improvement of up to 50.41% compared to the traditional Oracle method.