Revisiting Difficulty Control for Blockchain Systems
- The Bitcoin whitepaper states that security of the system is guaranteed as long as honest miners control more than half of the current total computational power. The whitepaper assumes a static difficulty, thus it is equally hard to solve a cryptographic proof-of-work puzzle for any given moment of the system history. However, the real Bitcoin network is using an adaptive difficulty adjustment mechanism. In this paper we introduce and analyze a new kind of attack on a mining difficulty retargeting function used in Bitcoin. A malicious miner is increasing his mining profits from the attack, named coin-hopping attack, and, as a side effect, an average delay between blocks is increasing. We propose an alternative difficulty adjustment algorithm in order to reduce an incentive to perform coin-hopping, and also to improve stability of inter-block delays. Finally, we evaluate the presented approach and show that the novel algorithm performs better than the original algorithm of Bitcoin.
Author: | Dmitry Meshkov, Alexander Chepurnoy, Marc Jansen |
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URL: | https://eprint.iacr.org/2017/731.pdf |
Document Type: | Article |
Language: | English |
Year of Completion: | 2017 |
Release Date: | 2019/04/30 |
Institutes: | Fachbereich 1 - Institut Informatik |
DDC class: | 000 Allgemeines, Informatik, Informationswissenschaft / 004 Informatik |
Licence (German): | No Creative Commons |