A Cost-efficient IoT Forensics Framework with Blockchain

IoT devices have been adopted widely in the last decade which enabled collection of various data from different environments. Data storage poses challenges since the data may be compromised during the storage and the integrity might be violated without being noticed. In such cases, integrity and data provenance are required in order to be able to detect the source of any incident and prove it in legal cases. To address these issues, blockchain provides excellent opportunities since it can protect the integrity of the data thanks to its distributed structure. However, it comes with certain costs as storing huge amount of data in a public blockchain will come with significant transaction fees. In this paper, we propose a highly cost effective and reliable digital forensics framework by exploiting multiple inexpensive blockchain networks as a temporary storage before the data is committed to Ethereum. To reduce Ethereum costs, we utilize Merkle trees which hierarchically stores hashes of the collected event data from IoT devices. We evaluated the approach on popular blockchains such as EOS, Stellar, and Ethereum by presenting a cost and security analysis. The results indicate that we can achieve significant cost savings without compromising the integrity of the data.

I. Introduction

The advancement in communication technologies, sensing items, and affordable computing devices has led us to the age of internet of things (IoT) which enables collecting diverse ambient data and communicate it to remote locations [1]. IoT is becoming the de facto technology in many domains including transportation, energy, healthcare, agriculture, hospitality, etc. [2]. In these applications, the data collected from various IoT devices are used to conduct extensive analytics to make informed decisions and take actions. In some scenarios, however, the data is very crucial to run critical infrastructure (i.e., power systems, transportation) and understand failures when they occur. In particular, if there are failures due to human errors or deliberate attacks, it is utmost important to be able to detect the cause of these failures and hold involved parties responsible. Therefore, the secure transmission and storage of IoT data is critical for such purposes.