Blockchain in internet of things: Challenges and Solutions (1608.05187v1)

Abstract: The Internet of Things IoT is experiencing exponential growth in research and industry, but it still suffers from privacy and security vulnerabilities. Conventional security and privacy approaches tend to be inapplicable for IoT, mainly due to its decentralized topology and the resource-constraints of the majority of its devices. BlockChain BC that underpin the crypto-currency Bitcoin have been recently used to provide security and privacy in peer-to-peer networks with similar topologies to IoT. However, BCs are computationally expensive and involve high bandwidth overhead and delays, which are not suitable for IoT devices. This position paper proposes a new secure, private, and lightweight architecture for IoT, based on BC technology that eliminates the overhead of BC while maintaining most of its security and privacy benefits. The described method is investigated on a smart home application as a representative case study for broader IoT applications. The proposed architecture is hierarchical, and consists of smart homes, an overlay network and cloud storages coordinating data transactions with BC to provide privacy and security. Our design uses different types of BCs depending on where in the network hierarchy a transaction occurs, and uses distributed trust methods to ensure a decentralized topology. Qualitative evaluation of the architecture under common threat models highlights its effectiveness in providing security and privacy for IoT applications.

Blockchain in Internet of Things: Challenges and Solutions

Overview

This paper addresses the pressing issues of privacy and security in the rapidly expanding field of the Internet of Things (IoT), proposing a blockchain-based architecture optimized for IoT applications. The unique computational and structural constraints of IoT networks, characterized by a decentralized topology and resource-limited devices, render traditional security measures inadequate. The authors propose a novel architecture that leverages the decentralization and security features of blockchain (BC) technology while mitigating its inherent overheads, such as computational expense and latency issues, unsuitable for IoT devices.

Architecture Description

The proposed architecture divides the IoT network into three tiers: smart homes, overlay networks, and cloud storage, each coordinated through blockchain to secure transactions while maintaining privacy. A remarkable feature of this system is its hierarchical structure, where different blockchain configurations adapt to various layers of the network. A qualitative investigation using a smart home as a case paper suggests that this BC-based architecture can provide enhanced security and privacy under typical threat models.

Key Components

1. Smart Home Layer: This includes all smart devices, a local blockchain for storing transactions securely by a dedicated resource-capable device (like a smart hub), and optional local storage.
2. Overlay Network: Mimicking Bitcoin's peer-to-peer nature, this layer facilitates inter-home communication, clustered for efficiency, and implements Tor for IP anonymity.
3. Cloud Storage: Essential for data storage and access by third-party service providers, using block numbers and data hashes for verification, ensuring secure data retrieval and management.

Evaluation of Security and Scalability

The proposed architecture is adept at managing common security threats in IoT, such as Denial of Service (DoS) attacks, modification attacks, and hacking attempts. Critical numerical evaluation sheds light on the architecture's ability to maintain constant performance overhead at best, with scalability hinging on the number of clusters—a factor influenced less by network node count, crucial for large IoT networks. The use of public/private key encryption and multisig transactions upholds data privacy and integrity.

Implications and Future Directions

This research presents a viable pathway to integrate blockchain technology in the IoT domain, preserving security and privacy while acknowledging IoT's inherent constraints. The hierarchical architecture tailors blockchain's benefits to specific IoT needs, thus contributing to more robust deployments of pervasive technologies such as smart cities and healthcare systems.

Future research could refine the architecture to further guard against distributed trust vulnerabilities, particularly the 51% attack, and enhance protections against sophisticated DoS and modification attacks. Given the decentralized and resource-limited nature of IoT, further exploration into lightweight yet resilient cryptographic solutions will be imperative. The infrastructure proposed here lays a solid foundation for such advancements, offering scalability and security without compromising the lightweight nature required for IoT's vast ecosystem.