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In a network of mining pools that secure Bitcoin-like blockchains, it is known that a self-interested mining pool can dishonestly siphon off another pool’s mining rewards by executing a block withholding (BWH) attack. In this paper, we show that a BWH attack is always unprofitable for an initial startup period which is at least one difficulty retarget interval (approximately 14 days for Bitcoin). Furthermore, we prove that the payback period to recoup this initial startup cost is always at least as long as the initial unprofitable startup interval, and we show numerically that it can be substantially longer. Thus, the decision of whether or not to execute a BWH attack is not a dominant strategy, and the so called Miner’s Dilemma is not in fact a dilemma.
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Response to Comment on “The lower Cambrian lobopodian Cardiodictyon resolves the origin of euarthropod brains”
Budd et al. challenge the identity of neural traces reported for the Cambrian lobopodian Cardiodictyon catenulum. Their argumentation is unsupported, as are objections with reference to living Onychophora that misinterpret established genomic, genetic, developmental, and neuroanatomical evidence. Instead, phylogenetic data corroborate the finding that the ancestral panarthropod head and brain is unsegmented, as in C. catenulum.
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- Award ID(s):
- 1754798
- PAR ID:
- 10491838
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science Magazine
- ISSN:
- 2776-8716
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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