RSA (Kryptosystem) - RSA (cryptosystem) -

An Analysis of Attacks on Blockchain Consensus

Date: 2016-11-20
Author(s): George Bissias, Brian Neil Levine, A. Pinar Ozisik, Gavin Andresen

Link to Paper

We present and validate a novel mathematical model of the blockchain mining process and use it to conduct an economic evaluation of the double-spend attack, which is fundamental to all blockchain systems. Our analysis focuses on the value of transactions that can be secured under a conventional double-spend attack, both with and without a concurrent eclipse attack. Our model quantifies the importance of several factors that determine the attack's success, including confirmation depth, attacker mining power, and any confirmation deadline set by the merchant. In general, the security of a transaction against a double-spend attack increases roughly logarithmically with the depth of the block, made easier by the increasing sum of coin turned-over (between individuals) in the blocks, but more difficult by the increasing proof of work required. In recent blockchain data, we observed a median block turnover value of 6 BTC. Based on this value, a merchant requiring a single confirmation is protected against only attackers that can increase the current mining power by 1% or less. However, similar analysis shows that a merchant that requires a much longer 72 confirmations (~12 hours) will eliminate all potential profit for any double-spend attacker adding mining power less than 40% of the current mining power.

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submitted by dj-gutz to myrXiv [link] [comments]

Why do I believe it was BCN destiny to be born in 2012?

Why do I believe it was BCN destiny to be born in 2012? Just look at this and see yourself:
1983 - Blind signatures were invented by David Chaum link 1997 - HashCash (proof of work system) was invented by Adam Back link
2001 - Ring signatures were invented by Ron Rivest, Adi Shamir, and Yael Tauman link
2003 - Mart n Abadi, Michael Burrows, and Ted Wobber presented "Moderately hard, memory-bound functions"link
2004 - Patrick P. Tsang and Victor K. Wei presented their paper "Short linkable ring signatures for e-voting, e-cash and attestation" link
2005 - Matthew Franklin and Haibin Zhang with "Unique Group Signatures" study link
2005 - Exponential memory-bound functions for proof of work protocols by Fabien Coelho link +2006 - "Traceable Ring Signature" by Fujisaki and Suzuki link
2008 - Bitcoin whitepaper by Satoshi Nakamoto link
2009 - Stronger key derivation via sequential memory-hard functions by Colin Percival link
2009 - First Bitcoin block was generated
2010 -2012 - Bitcoin Anonymity Problem Discussions link
2011 - An Analysis of Anonymity in the Bitcoin System, Fergal Reid and Martin Harrigwere link
5/15/2012 - Dorit Ron and Adi Shamir made Quantitative Analysis of the Full Bitcoin Transaction Graph link
6/8/2012 - Bytecoin Wiki started link
6/30/2012 - Bytecoin launch announcement link- first news
7/4/2012 - First BCN block was generated link
8/6/2012 - Destination Address Anonymization in Bitcoin (one-time addresses in BCN) link
10/19/2012 - Evaluating User Privacy in Bitcoin by Elli Androulaki, Ghassan O. Karame, Marc Roeschlin, Tobias Scherer, Srdjan Capkun. link
12/12/2012 -CryptoNote whitepaper v 1.0 link
12/13/2012 - Analysis of hashrate-based double-spending, Meni Rosenfeld link
10/17/2013 - CryptoNote whitepaper v 2.0 link
Here we see how the technology logically came to the advent of cryptocurrencies with ring signature and memory-bound function PoW implementation. Soon after Bitcoin's release the community started to raise concerns about its anonymity with multiple solutions and propositions. High concentration of theoretical papers on these topics in 2009-2011 most probably spurred the brightest minds to make attempts of practical e-cash with ring signatures realization. Therefore, BCN couldn't but appear in 2012.
Based on
submitted by joethejudge77 to BytecoinBCN [link] [comments]

How to create a wallet using Shamir Backup “Bitcoin Is ABOUT TO RECOVER In WAY NEVER SEEN For THIS REASON” TOM LEE Shares STARTLING New Secret Bitcoin Playground  Upgrading Trezor Firmware to Bitcoin Only What is Shamir Backup? Crypto Evangelist: Bitcoin - Like Every Asset - Is A Confidence Game  CNBC

RSA ( Rivest-Shamir-Adleman) ist eine der ersten Public-Key - Kryptosysteme und ist für die sichere Datenübertragung verwendet. In einem solchen Kryptosystem, die Verschlüsselungsschlüssel ist öffentlich und es unterscheidet sich von der Entschlüsselungsschlüssel, die (privat) geheim gehalten wird.In RSA wird diese Asymmetrie auf der praktischen Schwierigkeit der Basis Faktorisierung ... 2 Dorit Ron, Adi Shamir. record of this system 1, which consisted of about 180,000 HTML files. After . parsing and processing these files, we built a graph of all the Bitcoin addresses. and ... In Quantitative Analysis of the Full Bitcoin Transaction Graph by Dorit Ron and Adi Shamir the authors write: A very important feature of the Bitcoin network is that a transaction involving multiple sending addresses can only be carried out by the common owner of all those addresses, as it is demanded by the Bitcoin system that “Whoever sent this transaction owns all of these addresses ... These allegations were contested and Ron and Shamir later retracted their claim. Nakamoto’s involvement with bitcoin does not appear to extend past mid-2010. In April 2011, Nakamoto communicated with a bitcoin contributor, saying that he had “moved on to other things”. Bitcoin. Bitcoin ist die weltweit führende Kryptowährung auf Basis eines dezentral organisierten Buchungssystems. Zahlungen werden kryptographisch legitimiert und über ein Netz gleichberechtigter Rechner (peer-to-peer) abgewickelt.Anders als im klassischen Banksystem üblich, ist kein zentrales Clearing der Geldbewegungen notwendig. Eigentumsnachweise an Bitcoin werden in persönlichen ...

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How to create a wallet using Shamir Backup

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