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Statistical detection of selfish mining in proof-of-work blockchain systems.

Sheng-Nan Li^1,2, Carlo Campajola^1,2,3,4, Claudio J Tessone^5,6

¹Blockchain and Distributed Ledger Technologies, Faculty of Business, Economics and Informatics, University of Zurich, 8050, Zurich, Switzerland.

Scientific Reports

|March 16, 2024

Summary

This study reveals strategic mining behaviors in cryptocurrencies like Monacoin and Bitcoin Cash. Researchers developed a statistical test to detect selfish mining attacks, finding evidence of such practices and even mining cartels.

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Area of Science:

* Cryptocurrency security and blockchain network analysis.
* Applied cryptography and distributed systems.

Background:

* Proof-of-work (PoW) is the core of many cryptocurrency validation networks, relying on miners to solve complex problems.
* Miners are incentivized to act honestly, but strategic behaviors like selfish mining pose a security concern.
* Selfish mining involves withholding newly discovered blocks to gain an unfair advantage.

Purpose of the Study:

* To empirically investigate the occurrence of strategic mining behaviors in popular cryptocurrencies.
* To develop and apply a statistical method for detecting selfish mining attacks.
* To identify evidence of coordinated selfish mining activities.

Main Methods:

* Developed a statistical test analyzing successive block discovery times for anomalies.
* Applied heuristics-based address clustering to enhance detection accuracy.
* Analyzed data from Bitcoin, Litecoin, Monacoin, Ethereum, and Bitcoin Cash.

Main Results:

* Detected a significant presence of abnormal mining behavior in Monacoin and Bitcoin Cash.
* Observed a lesser extent of abnormal behavior in Ethereum.
* Identified potential mining cartels engaged in coordinated selfish mining in Monacoin.

Conclusions:

* Strategic mining behaviors, including selfish mining, are present in real-world cryptocurrency networks.
* The proposed statistical method effectively detects these illicit activities.
* Empirical evidence supports the vulnerability of PoW systems to strategic miner manipulation.