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“Tail Removal Block Validation: Implementation and Analysis”

Authors: Jan Kucera and Geir Hovland,
Affiliation: Bismuth Foundation and University of Agder
Reference: 2018, Vol 39, No 3, pp. 151-156.

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Keywords: Blockchain, block times, long tail removal, feedback control

Abstract: In this paper a solution for the removal of long tail blocktimes in a proof-of-work blockchain is proposed, implemented and analysed. Results from the mainnet of the Bismuth blockchain demonstrate that the variances in the key variables, difficulty level and blocktime, were approximately halved after the tail removal code was enabled. Low variances in difficulty and blocktimes are desirable for timely execution of transactions in the network as well as reduction of unwanted oscillations in the feedback control problem.

PDF PDF (496 Kb)        DOI: 10.4173/mic.2018.3.1

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  title={{Tail Removal Block Validation: Implementation and Analysis}},
  author={Kucera, Jan and Hovland, Geir},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}


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