Tamper-Evident Data and Model Provenance for IoT-Based Machine Learning Using Blockchain and Off-Chain Storage

Machine learning models increasingly rely on continuously generated sensor data for automated decision-making in Internet of Things (IoT) environments. The distributed and often insecure nature of IoT infrastructures introduces risks related to data manipulation, lack of traceability, and unverifiable model evolution. Existing solutions typically address isolated aspects such as data security or access control but do not provide end-to-end provenance across the machine learning lifecycle. This paper proposes a tamper-evident data and model provenance framework for IoT-based machine learning that integrates blockchain with off-chain storage. The framework records cryptographic hashes and metadata of data, preprocessing outputs, and trained models on-chain while maintaining large artifacts off-chain to ensure scalability. Smart contracts establish verifiable linkage among lifecycle artifacts and automate provenance registration. The framework is evaluated in a simulated IoT–ML pipeline under integrity attack scenarios including data manipulation, model tampering, and metadata modification. Experimental results demonstrate reliable detection of unauthorized modifications with low verification latency and constant on-chain storage per record under controlled conditions. These findings indicate the feasibility of hybrid blockchain architectures for tamper-evident provenance in IoT-based machine learning systems, while highlighting the need for further validation in real-world deployments.