ZeroBlock: Timestamp-Free Prevention of Block-Withholding Attack in Bitcoin

TL;DR

ZeroBlock introduces a timestamp-free method to prevent block-withholding attacks in Bitcoin, enhancing security without relying on potentially forgeable timestamps, and remains effective despite network node churn.

Contribution

It presents a novel timestamp-free approach to prevent selfish mining in Bitcoin, addressing limitations of previous timestamp-dependent solutions.

Findings

ZeroBlock effectively prevents block-withholding attacks.

The solution is resilient to node churn in the network.

It does not rely on forgeable timestamps.

Abstract

Bitcoin was recently introduced as a peer-to-peer electronic currency in order to facilitate transactions outside the traditional financial system. The core of Bitcoin, the Blockchain, is the history of the transactions in the system maintained by all miners as a distributed shared register. New blocks in the Blockchain contain the last transactions in the system and are added by miners after a block mining process that consists in solving a resource consuming proof-of-work (cryptographic puzzle). The reward is a motivation for mining process but also could be an incentive for attacks such as selfish mining. In this paper we propose a solution for one of the major problems in Bitcoin : selfish mining or block-withholding attack. This attack is conducted by adversarial or selfish miners in order to either earn undue rewards or waste the computational power of honest miners. Contrary to recent solutions, our solution, ZeroBlock, prevents block-withholding using a technique free of timestamp that can be forged. Moreover, we show that our solution is compliant with nodes churn.