LSB: A Lightweight Scalable BlockChain for IoT Security and Privacy (1712.02969v1)

Abstract: BlockChain (BC) has attracted tremendous attention due to its immutable nature and the associated security and privacy benefits. BC has the potential to overcome security and privacy challenges of Internet of Things (IoT). However, BC is computationally expensive, has limited scalability and incurs significant bandwidth overheads and delays which are not suited to the IoT context. We propose a tiered Lightweight Scalable BC (LSB) that is optimized for IoT requirements. We explore LSB in a smart home setting as a representative example for broader IoT applications. Low resource devices in a smart home benefit from a centralized manager that establishes shared keys for communication and processes all incoming and outgoing requests. LSB achieves decentralization by forming an overlay network where high resource devices jointly manage a public BC that ensures end-to-end privacy and security. The overlay is organized as distinct clusters to reduce overheads and the cluster heads are responsible for managing the public BC. LSB incorporates several optimizations which include algorithms for lightweight consensus, distributed trust and throughput management. Qualitative arguments demonstrate that LSB is resilient to several security attacks. Extensive simulations show that LSB decreases packet overhead and delay and increases BC scalability compared to relevant baselines.

Overview of "LSB: A Lightweight Scalable Blockchain for IoT Security and Privacy"

The paper "LSB: A Lightweight Scalable Blockchain for IoT Security and Privacy" proposes a novel framework designed to integrate blockchain technology effectively into the Internet of Things (IoT) ecosystem while addressing critical challenges associated with conventional blockchain implementations. The authors highlight that blockchain (BC), with its immutable, distributed ledger, offers intrinsic security and privacy benefits that can lend themselves to the needs of IoT environments. However, issues such as computational expense, scalability limitations, bandwidth overheads, and latency make established BC technologies unsuitable for direct deployment in IoT contexts. This paper introduces the Lightweight Scalable Blockchain (LSB), specifically optimized for IoT applications, with an emphasis on a smart home environment as a representative scenario.

Key Features and Contributions

The paper makes several critical contributions by presenting a hierarchical framework that partitions the architecture into two tiers: the smart home tier and the overlay tier. This architecture utilizes a local Block Manager (LBM) for device transactions within a smart home and introduces Overlay Block Managers (OBMs) which coordinate across a decentralized network of higher resource devices in the overlay network. These clusters minimize network overhead, as OBMs are responsible for maintaining public blockchain, thus ensuring that IoT transactions are efficiently handled within this framework.

Several optimizations are proposed to enhance transaction efficiency and system robustness:

• Lightweight Consensus Algorithm: LSB features a tailored consensus approach, abandoning resource-intensive methods like Proof of Work (PoW) or Proof of Stake (PoS) in favor of a time-based algorithm to accommodate the processing constraints of IoT devices.
• Distributed Trust and Throughput Management: LSB utilizes direct and indirect evidences to accumulate trust among OBMs, which dynamically reduces the number of transactions that need validation as trust bolsters. Additionally, a distributed throughput management strategy dynamically regulates transaction handling to accommodate network growth without loss of efficiency.

Security and Performance Evaluations

Qualitative analysis within the paper identifies LSB as being robust against a range of conventional cyber threats, including Denial of Service attacks, dropping attacks, and modification attacks among others, due to its decentralized security model and adaptive verification process. Quantitative simulations demonstrate LSB’s efficiency in reducing transaction overhead and latency compared to classical BC methods, such as Bitcoin.

For instance, comprehensive simulation outcomes depict the implications of proposed adjustments to consensus-period and utilization regulation on the performance of the LSB system under fluctuating network loads. Such regulatory mechanisms ensure that network utilization remains within desirable limits to provide self-scaling capabilities—a key requirement for IoT extensions of blockchain.

Future Implications and Research Directions

While this framework presents a viable path forward for hybrid blockchain and IoT solutions by significantly reducing latency and resource requirements, the paper opens up future avenues for enhancements in terms of implementing prototypes in real-world contexts and expanding the security model to consider the potential compromise of local block managers.

In conclusion, this body of work significantly advances the conversation on blockchain adaptability in IoT by crafting a resource-effective and scalable modality, with a strong focus on maintaining security and privacy integrity. This research portrays a promising trajectory for further exploration and potential application across varied IoT deployments such as smart grids and vehicular networks. The practical and theoretical implications underscore LSB’s potential role as a foundational framework in the evolving intersection of blockchain technology and IoT ecosystems.