Rethinking Blockchains in the Internet of Things Era from a Wireless Communication Perspective

TL;DR

This paper examines how wireless communication reliability impacts blockchain security in IoT networks, analyzing the tradeoffs between communication and computing power, and demonstrating how unreliable links can lower attack costs.

Contribution

It introduces a new perspective on blockchain security in IoT by considering wireless communication reliability and provides a lower bound on computing power needed for attacks under these conditions.

Findings

Adversarial nodes can tamper with blocks more easily when communication is unreliable.

Communication reliability significantly affects the security threshold of blockchain in IoT.

Simulation confirms that hindering block propagation reduces the attacker's required computing power.

Abstract

Due to the rapid development of Internet of Things (IoT), a massive number of devices are connected to the Internet. For these distributed devices in IoT networks, how to ensure their security and privacy becomes a significant challenge. The blockchain technology provides a promising solution to protect the data integrity, provenance, privacy, and consistency for IoT networks. In blockchains, communication is a prerequisite for participants, which are distributed in the system, to reach consensus. However, in IoT networks, most of the devices communicate through wireless links, which are not always reliable. Hence, the communication reliability of IoT devices influences the system security. In this article, we rethink the roles of communication and computing in blockchains by accounting for communication reliability. We analyze the tradeoff between communication reliability and computing power in blockchain security, and present a lower bound to the computing power that is needed to conduct an attack with a given communication reliability. Simulation results show that adversarial nodes can succeed in tampering a block with less computing power by hindering the propagation of blocks from other nodes.