Simon Barber - Senior Software Engineer - Cisco Meraki ...

Today in History 02/08





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Estimation of Miner Hash Rates and Consensus on Blockchains

arXiv:1707.00082
Date: 2017-07-01
Author(s): A. Pinar Ozisik, George Bissias, Brian Levine

Link to Paper


Abstract
We make several contributions that quantify the real-time hash rate and therefore the consensus of a blockchain. We show that by using only the hash value of blocks, we can estimate and measure the hash rate of all miners or individual miners, with quanti able accuracy. We apply our techniques to the Ethereum and Bitcoin blockchains; our solution applies to any proof-of-work-based blockchain that relies on a numeric target for the validation of blocks. We also show that if miners regularly broadcast status reports of their partial proof-of- work, the hash rate estimates are signi cantly more accurate at a cost of slightly higher bandwidth. Whether using only the blockchain, or the additional information in status reports, merchants can use our techniques to quantify in real-time the threat of double-spend attacks.

References
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Rethinking Large-Scale Consensus

Cryptology ePrint Archive: Report 2018/302
Date: 2018-03-29
Author(s): Rafael Pass, Elaine Shi

Link to Paper


Abstract
In this position paper, we initiate a systematic treatment of reaching consensus in a permissionless network. We prove several simple but hopefully insightful lower bounds that demonstrate exactly why reaching consensus in a permissionless setting is fundamentally more difficult than the classical, permissioned setting. We then present a simplified proof of Nakamoto's blockchain which we recommend for pedagogical purposes. Finally, we survey recent results including how to avoid well-known painpoints in permissionless consensus, and how to apply core ideas behind blockchains to solve consensus in the classical, permissioned setting and meanwhile achieve new properties that are not attained by classical approaches.

References
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Cliffs Barber Corral - YouTube Interview with Oron Barber & Eilon Arad about Bitcoin Technology Piain Kom och ha lite god times - YouTube BARBER MAO’S

Bitter to Better — How to Make Bitcoin a Better Currency Simon Barber 1, Xavier Boyen , Elaine Shi 2?, and Ersin Uzun 1 Palo Alto Research Center 2 University of California, Berkeley Abstract. Bitcoin is a distributed digital currency which has attracted a substan- tial number of users. We perform an in-depth investigation to understand what made Bitcoin so successful, while decades of ... Bitter to Better : How to Make Bitcoin a Better Currency. By Simon Barber, Xavier Boyen, Elaine Shi, and Ersin Uzun. In Financial Cryptography (FC 2012), volume 7397 of Lecture Notes in Computer Science, pages 399-414. Springer, 2012. Abstract. Bitcoin is a distributed digital currency which has attracted a substantial number of users. We perform an in-depth investigation to understand what ... View Simon Barber’s profile on LinkedIn, the world's largest professional community. Simon has 13 jobs listed on their profile. See the complete profile on LinkedIn and discover Simon’s ... Bitter to Better — How to Make Bitcoin a Better Currency Simon Barber 1, Xavier Boyen , Elaine Shi 2, and Ersin Uzun 1 Palo Alto Research Center 2 University of California, Berkeley Abstract. Bitcoin is a distributed digital currency which has attracted a substan-tial number of users. We perform an in-depth investigation to understand what made Bitcoin so successful, while decades of ... Simon Barber Founder @devicescape, advisor @ozmo-devices. Technical editor of 802.11. Researcher @xerox-parc. Highly creative and innovative multidisciplinarian. Software Engineer Silicon Valley University of Cambridge. 71 Connections There was a problem loading your content. Log in or sign up to find connections to Simon. Experience Ozmo Devices. Advisor. Devicescape. Founder, CTO 2001 - 2008 ...

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Cliffs Barber Corral - YouTube

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. 12 Year Old Boy Humiliates Simon Cowell ... Barber belittled by CNN's Brooke Baldwin returns to 'Tucker Carlson Tonight' - Duration: 6:47. Fox News Recommended for you. New; 6:47. Life Is Good ... This crazy footage of what appears to be a meteor over south San Antonio today at 2:02AM. Hej!går live nu. This video is unavailable. Watch Queue Queue http://calvinayre.com - Oron Barber & Eilon Arad of BetcoinTech talks about Bitcoin, the technology behind it and how it can change and influence the payment...

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