Homeland Security Bill is Overkill, Bitcoin Isn't Good For

Agreement with Satoshi – On the Formalization of Nakamoto Consensus

Cryptology ePrint Archive: Report 2018/400
Date: 2018-05-01
Author(s): Nicholas Stifter, Aljosha Judmayer, Philipp Schindler, Alexei Zamyatin, Edgar Weippl

Link to Paper

The term Nakamoto consensus is generally used to refer to Bitcoin's novel consensus mechanism, by which agreement on its underlying transaction ledger is reached. It is argued that this agreement protocol represents the core innovation behind Bitcoin, because it promises to facilitate the decentralization of trusted third parties. Specifically, Nakamoto consensus seeks to enable mutually distrusting entities with weak pseudonymous identities to reach eventual agreement while the set of participants may change over time. When the Bitcoin white paper was published in late 2008, it lacked a formal analysis of the protocol and the guarantees it claimed to provide. It would take the scientific community several years before first steps towards such a formalization of the Bitcoin protocol and Nakamoto consensus were presented. However, since then the number of works addressing this topic has grown substantially, providing many new and valuable insights. Herein, we present a coherent picture of advancements towards the formalization of Nakamoto consensus, as well as a contextualization in respect to previous research on the agreement problem and fault tolerant distributed computing. Thereby, we outline how Bitcoin's consensus mechanism sets itself apart from previous approaches and where it can provide new impulses and directions to the scientific community. Understanding the core properties and characteristics of Nakamoto consensus is of key importance, not only for assessing the security and reliability of various blockchain systems that are based on the fundamentals of this scheme, but also for designing future systems that aim to fulfill comparable goals.

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O Preço do Bitcoin pode chegar a 98500 dólares segundo analistas de Wall Street

O preço do bitcoin pode subir para até $ 98.500, de acordo com analistas da empresa de serviços financeiros e de investimentos Wedbush Securities.
Um relatório dos analistas Gil Luria e Aron Turner, que tem sido referenciado em StreetInsider.com, tem uma visão extremamente positiva do bitcoin, sugerindo que a moeda digital tem o potencial de sacudir o espaço de pagamentos atual.
Intitulado Bitcoin: O Valor Intrínseco Como Um Canal Para Rede de Tecnologia Disruptiva De Pagamento, o relatório afirma:
"Entre outras facetas, acreditamos que o bitcoin e a tecnologia associada à ele representam uma potencial ruptura que mudará o jogo para as nossas empresas de pagamento."
Os autores argumentam ainda cryptomoeda oferece uma "alternativa poderosa para redes de marca", devido ao seu processamento descentralizado, novas funcionalidades e utilização de taxas baseadas no mercado.
O preço do bitcoin tem sido um Hot Topic desde a semana passada, com a moeda digital aumentando para os vertiginosos US$ 1165 no sábado, de acordo com theCoinDesk BPI. Em Mt. Gox, o preço superou US$ 1242, ultrapassando o preço do ouro pela primeira vez (o ouro estava em 1241 dólares por onça).
Erik Voorhees, que vendeu o site de apostas SatoshiDice por 126.315 BTC este ano, disse que isto mostrou em que "trunfo respeitável" o bitcoin está se tornando.
"Claramente, o Bitcoin não é mais só uma moeda insignificante. Ele está jogando na grande liga - valendo mais do que uma parte do Google ou da Apple, e até mesmo mais do que uma onça de ouro", disse ele na época.
O valor tem flutuado nestes últimos dias, com o preço, no momento da escrita deste artigo, pairando em torno de US$ 1071.
Sobe ou desce?
Muitas pessoas têm afirmado que o valor alto atual é meramente um aumento temporário e que em breve cairá para o mesmo nível observado em setembro e outubro (cerca de US $ 120 - $ 150), ou talvez ainda mais baixos.
Luria e Turner discordam, acreditando que o valor vai continuar a aumentar nos próximos anos. Eles disseram:
"Acreditamos que a subida dos preços do bitcoin ajudou a construir a rede, e assim, consolidando o seu valor, especialmente vis-à-vis outras moedas alternativas. Com base neste quadro, nós postulamos que os preços atuais refletem um auge de 1% do total da demanda potencial do Bitcoin em 10 anos".
No mês passado, os gêmeos Winklevoss comentaram que eles previam um aumento de 100 vezes no preço do Bitcoin. Na época de seus comentários, o preço do bitcoin foi de US $ 343 de modo que o valor já aumentou mais de 211%.
Falando à CNBC na conferência Dealbook em Nova York, Tyler Winklevoss, que estava envolvido na criação do Facebook, disse: "Algumas pessoas definitivamente o veem [bitcoin] como um Ouro 2.0".
Os Milhões de Clamath
Ex-executivo do Facebook, Chamath Palihapitiya, também é muito otimista a respeito do bitcoin.
No final de outubro, ele revelou que possuía US$ 5 milhões no valor da moeda digital, mas disse que estava esperando para alcançar cerca de 10-15 milhões de dólares com ela. Em 29 de outubro, o preço do bitcoin foi ligeiramente inferior a US $ 200, por isso é provável que ele tinha cerca de 25.000 BTC. Essa quantidade de bitcoins agora vale mais de US $ 26 milhões, por isso parece que Palihapitiya conseguiu o que desejava e um pouco mais.
Em maio, ele escreveu um artigo para a Bloomberg afirmando que o Bitcoin pode se tornar uma "versão melhorada" do ouro, ou mesmo um substituto para o metal precioso. Com todo o ouro do mundo totalizando aproximadamente US $ 8 trilhões, Palihapitiya disse que se o bitcoin substituisse o ouro como reserva de valor cada bitcoin custaria quase $ 400.000, uma vez que todos os 21 milhões de bitcoins fossem minados (US $ 8 trilhões/21milhões BTC).
"Se o Bitcoin se tornar algo maior - uma moeda de reserva útil, então cuidado: Seu valor será muito superior $ 400.000", escreveu ele, acrescentando:
"Eu pessoalmente acho que o Bitcoin já é superior ao ouro. O seu papel como moeda ainda está para ser determinado, mas ao longo da próxima década, ser o Ouro 2.0 será suficiente, considerando que isso representaria um retorno de mais de 3.000 vezes".
O problema com a volatilidade
Enquanto muitas pessoas acreditam que, a longo prazo, o preço do bitcoin será consideravelmente maior do que é agora, a visão comum é que a sua volatilidade continuará no curto prazo.
Luria e Turner explicaram em seu relatório que esta volatilidade é o resultado de um "processo de descoberta de preço estendida". Acredita-se quanto maiores forem os ganhos líquidos do bitcoin e quanto mais ele for amplamente aprovado, maior a probabilidade de se estabilizar o seu preço.
Atualmente, a volatilidade da moeda é o fator que está fazendo com que um alto percentual de pessoas leve o bitcoin a sério.
Na Universidade da Califórnia em San Diego, a pesquisadora Sarah Meiklejohn, que escreveu um artigo chamado Um Punhado DE Bitcoins: Caracterizando Pagamentos Entre Homens Sem Nome, disse ao CoinDesk que a coisa que a deixa "mais nervosa" a respeito do bitcoin é a sua volatilidade .
"É um problema do tipo galinha ou ovo. Você precisa de mais pessoas adotando o bitcoin a fim de estabilizar isso, mas as pessoas estão se afastando porque elas o veem como volátil e como um investimento de risco", disse ela.
A solução para este problema ainda não está claro, mas a comunidade bitcoin e os negócios dentro dele continuam a trabalhar arduamente para tornar mais fácil para os comerciantes aceitar bitcoins e para os consumidores obtê-los e em seguida gastá-los.
Qual você acha que é a chave para a estabilidade do bitcoin?
Traduzido por Sarah Alexandre Original em: http://www.coindesk.com/bitcoin-price-reach-98500-say-wall-street-analysts/
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A Bitcoin-Style Currency for Central Banks: The Bank of England asked researchers to invent a digital currency with a more centralized design.

This is an automatic summary, original reduced by 70%.
Now researchers have invented a Bitcoin-like system that could make digital cash more practical by allowing a central bank such as the Federal Reserve to control it.
The system, RSCoin, was designed by researchers Sarah Meiklejohn and George Danezis at University College London, at the suggestion of the U.K.'s central bank, the Bank of England.
RSCoin's ledger is solely in the hands of the central bank, which would also retain a special encryption key that could be used to control the money supply-for example, to take actions like the quantitative easing programs the Federal Reserve and other central banks put in place after the 2008 financial crisis.
A small collection of third-party organizations would be chosen by the central bank to process new transactions and submit them for inclusion in the central ledger.
Bhagwan Chowdhry, a professor of finance at UCLA, says that by adopting a system like RSCoin, central banks could enable the financial system to serve people much better.
One reason a central bank might like a digital currency is that its ledger provides a very detailed record of financial activity.
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One America News Investigates: Biden’s Bribe Tapes - PART 2 MONUMENTAL BITCOIN CHART NOBODY IS WATCHING RIGHT NOW (btc crypto live market news analysis today ta Todays Message: See from a higher perspective 07-10-20_Sarah_Mike Shannon_Zoey_wait heel come and place command Panel: Technical Challenges: Blockchain Scalability and Others - Blockchain Workshops - Sydney 2015

Sarah Meiklejohn, a computer scientist at University College London, said that when Bitcoin first emerged, law enforcement officials were terrified. However, as forensic technologies have caught up, the means to track criminals now exist. NewsBTC is a news service that covers bitcoin news, technical analysis & forecasts for bitcoin and With academic research on Bitcoin and cryptocurrencies still in its infancy, Sarah Meiklejohn's track record of publications in the area stands out. The UCL computer science professor has explored topics ranging from anonymity in Bitcoin to how a central bank could go about issuing a cryptocurrency. Topics covered included: What techniques can be used to deanonymize Bitcoin users How Bitcoin's That’s according to Sarah Meiklejohn, a computer scientist at University College London. What Meiklejohn said is that the introduction of bitcoin initially sprouted fear within the law University of California, San Diego researcher Sarah Meiklejohn recently completed a paper that traced the movements of bitcoin in April using heuristics, a specific problem-solving technique that I asked Sarah Meiklejohn, a computer scientist at the University of California, San Diego, for her thoughts. Meiklejohn says that that 194,993-bitcoin transaction was probably done by Bitstamp

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One America News Investigates: Biden’s Bribe Tapes - PART 2

BITCOIN HALVING IS ABOUT TO SHAKE THE CRYPTO MARKET (btc crypto live price analysis news today 2020 - Duration: 54:56. Crypto Crew University 33,405 views 54:56 Support the show, consider donating: 1MjytrKGNVYkqPfmBKrm3MJzm36vH6m8ZR (http://bit.ly/2bNodUa) With academic research on Bitcoin and cryptocurrencies still ... CNBC's Bob Pisani reports on where bitcoin could go from its recent new high. » Subscribe to CNBC: http://cnb.cx/SubscribeCNBC About CNBC: From 'Wall Street'... Please LIKE - SHARE - COMMENT - SUBSCRIBE - SUPPORT thank you, namaste Please consider supporting this page so that I can continue to bring these and all the other free messages through to ... Seminar with Sarah Meiklejohn at University College London 16th October 2014 Link to Research Paper: A Fistful of Bitcoins: Characterizing Payments Among

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