BitPaper


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2016-12-09

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2016-07-13

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Producing financial metrics for a virtual company, such as Bitcoin

2014-09-20

Bitcoin and many other virtual currencies exist. Here we argue that it is more accurate and useful to view Bitcoin and other services built on the blockchain as virtual companies rather than currencies. When analysing Bitcoin as a company we are able to calculate financial metrics which can be used to evaluate the company. These financial metrics were found to be useful for gaining an understanding of the financial health of Bitcoin.

The Mini-Blockchain Scheme

2014-07-01

Almost all P2P crypto-currencies prevent double spending and similar such attacks with a bulky "blockchain" scheme, and the ones which do not typically use some sort of pseudo-centralized solution to manage the transactions. Here I propose a purely P2P crypto-currency scheme with a finite blockchain, dubbed the "mini-blockchain". Each time a new block is solved the oldest block is trimmed from the end of the mini-blockchain so that it always has the same number of blocks. It is argued that the loss of security this trimming process incurs can be solved with a small "proof chain" and the loss of coin ownership data is solved with a database which holds the balance of all non-empty addresses, dubbed the "account tree". The proof chain secures the mini-blockchain and the mini-blockchain secures the account tree. This paper will describe the way in which these three mechanisms can work together to form a system which provides a high level of integrity and security, yet is much slimmer than all other purely P2P currencies. It also offers other potential benefits such as faster transactions and lower fees, quicker network synchronization, support for high levels of traffic, more block space for custom messages, and increased anonymity.

PoS Cryptocurrency wtih No Blockchain

2014-06-01

There are some alternative Cryptocurrency systems which claim that they are based on PoS are actually based on PoSTW which denotes the Proof of Stake(coin), Time(day) and Work(hashing), while the other pure PoS Cryptocurrency systems are actually centralized. In this paper we propose a new framework of Cryptocurrency system. The major parts what we have changed include, a fast transparent distribution solution which can avoid deceptions between the sponsor and the audience, removing the bloated history transactions from data synchronization, no mining, no blockchain, it's environmentally friendly, no checkpoint, no exchange hub needed, it's truly decentralized and purely based on proof of stake. The logic is very simple and intuitive, 51% of stakes talk. The highlight of this paper is a proposal of a new concise data synchronization mechanism named "Converged Consensus" which ensures the system reaches a consistent distributed consensus. We think the famous blockchain mechanism based on PoW is no longer an essential element of a Cryptocurrency system. In aspect of security, we propose TILP & SSS strategies to secure our system. At the end, we try to give an explicit definition of decentralization.

Nidaba: a distributed scalable PKI with a stable price for certificate operations

2014-05-03

A distributed PKI (naming system) would solve the problem of trusting the authorities in the key technologies behind the Internet. Its creation is a complex task, since the system has to be scalable, has to provide a stable price for certificate registration and has to prevent cyber squatting. Nidaba has all the mentioned properties, moreover it protects a blockchain from being forked behindhand and it has the same level of protection as Bitcoin does.

Nidaba: a distributed scalable PKI with a stable price for certificate operations

2014-05-03

A distributed PKI (naming system) would solve the problem of trusting the authorities in the key technologies behind the Internet. Its creation is a complex task, since the system has to be scalable, has to provide a stable price for certificate registration and has to prevent cyber squatting. Nidaba has all the mentioned properties, moreover it protects a blockchain from being forked behindhand and it has the same level of protection as Bitcoin does.

Thinking in Blockchains: Defining the Cryptoeconomic System

2014-04-03

This overly simplified whitepaper is intended to serve as an introduction to the mathematically demonstrable economic systems which exist within the cryptocurrency economy ('cryptoeconomy'). It makes no attempt to argue this point. With almost $1,000,000,000 invested in over 500 altcoins, the debate over the profitability or viability of the 'altmarket' (the market of cryptocurrencies other than Bitcoin) has ended.

Darkcoin: Peer­to­Peer Crypto­Currency with Anonymous Blockchain Transactions and an Improved Proof­of­Work System

2014-03-18

Darkcoin is the first privacy centric cryptographic currency based on Satoshi Nakamoto's Bitcoin. DarkSend, a technology for sending anonymous block transactions is incorporated directly into the client using extensions to the core protocol. An improved proof-of-work using a chain of hashing algorithms replaces the SHA256 algorithm and will result in a slower encroachment of more advanced mining technologies (such as ASIC devices). DarkGravityWave is implemented to provide quick response to large mining power fluctuations.

Bitshares X: Decentralized Bank & Exchange

2014-02-14

Crypto-currencies such as Bitcoin have opened the door to an economic revolution in the information age as significant as the industrial revolution before it. BitShares X is the first experiment in taking the ideas introduced by Bitcoin to the next level by producing trust-free digital assets that have the potential to track the price of anything. In this paper we share the details of how BitShares X is designed and functions

mananger of hexoproject

2014-01-01

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Colored Coins - BitcoinX

2013-11-26

Bitcoin is the world's first decentralized digital currency, allowing the easy storage and transfer of cryptographic tokens, using a peer-to-peer network to carry information, hashing as a synchronization signal to prevent double-spending, and a powerful scripting system to determine ownership of the tokens. There is a growing technology and business infrastructure supporting it. By the original design bitcoins are fungible, acting as a neutral medium of exchange. However, by carefully tracking the origin of a given bitcoin, it is possible to "color" a set of bitcoins to distinguish it from the rest. These bitcoins can then have special properties supported by either an issuing agent or by public agreement, and have value independent of the face value of the underlying bitcoins. Such colored bitcoins can be used for alternative currencies, commodity certificates, smart property, and other financial instruments such as stocks and bonds. Because colored coins make use of the existing Bitcoin infrastructure and can be stored and transferred without the need for a third party, and even be exchanged for one another in an atomic transaction, they can open the way for the decentralized exchange of things that are not possible by traditional methods. In this paper we will discuss the implementation details of colored coins and some of their use cases.

CryptoNote v 2.0

2013-10-07

"Bitcoin" [1] has been a successful implementation of the concept of p2p electronic cash. Both professionals and the general public have come to appreciate the convenient combination of public transactions and proof-of-work as a trust model. Today, the user base of electronic cash is growing at a steady pace; customers are attracted to low fees and the anonymity provided by electronic cash and merchants value its predicted and decentralized emission. Bitcoin has effectively proved that electronic cash can be as simple as paper money and as convenient as credit cards. Unfortunately, Bitcoin suffers from several deficiencies. For example, the system's distributed nature is inflexible, preventing the implementation of new features until almost all of the network users update their clients. Some critical flaws that cannot be fixed rapidly deter Bitcoin's widespread propagation. In such inflexible models, it is more efficient to roll-out a new project rather than perpetually fix the original project. In this paper, we study and propose solutions to the main deficiencies of Bitcoin. We believe that a system taking into account the solutions we propose will lead to a healthy competition among different electronic cash systems. We also propose our own electronic cash, "CryptoNote", a name emphasizing the next breakthrough in electronic cash.

PPCoin: Peer-to-Peer Crypto-Currency with Proof-of-Stake

2012-08-19

A peer-to-peer crypto-currency design derived from Satoshi Nakamoto's Bitcoin. Proof-of-stake replaces proof-of-work to provide most of the network security. Under this hybrid design proof-of-work mainly provides initial minting and is largely non-essential in the long run. Security level of the network is not dependent on energy consumption in the long term thus providing an efficient efficient and more cost-competitive peer-to-peer crypto-currency. Proof-of-stake is based on coin age and generated by each node via a hashing scheme bearing similarity to Bitcoin's but over limited search space. Block chain history and transaction settlement are further protected by a centrally broadcasted checkpoint mechanism.

Bitcoin: A Peer-to-Peer Electronic Cash System

2008-11-01

Abstract. A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without going through a financial institution. Digital signatures provide part of the solution, but the main benefits are lost if a trusted third party is still required to prevent double-spending. We propose a solution to the double-spending problem using a peer-to-peer network. The network timestamps transactions by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work. The longest chain not only serves as proof of the sequence of events witnessed, but proof that it came from the largest pool of CPU power. As long as a majority of CPU power is controlled by nodes that are not cooperating to attack the network, they'll generate the longest chain and outpace attackers. The network itself requires minimal structure. Messages are broadcast on a best effort basis, and nodes can leave and rejoin the network at will, accepting the longest proof-of-work chain as proof of what happened while they were gone.

Ripple: Ripple Gateways

A Ripple gateway is a business that provides onboard and offboard ramps to the Ripple network. Ripple is free open source software and no agreement with Ripple Labs is necessary. However, Ripple Labs would like to be of assistance in integration planning and implementation. This is a primer on considerations related to integration of the gateway service.

Ripple Market Makers

Ripple Labs is a technology company founded in 2012, financed by leading investors (Andreessen Horowitz, Google Ventures, IDG, etc.), and comprised of employees with experience in finance, payments, security, technology, and policy (Google, Goldman Sachs, Microsoft, E-Loan, Promontory Financial Group, US Federal Reserve, Square, Visa, etc.).

Ethereum White Paper: A NEXT GENERATION SMART CONTRACT & DECENTRALIZED APPLICATION PLATFORM

When Satoshi Nakamoto first set the Bitcoin blockchain into motion in January 2009, he was simultaneously introducing two radical and untested concepts. The first is the "bitcoin", a decentralized peer-to-peer online currency that maintains a value without any backing, intrinsic value or central issuer. So far, the "bitcoin" as a currency unit has taken up the bulk of the public attention, both in terms of the political aspects of a currency without a central bank and its extreme upward and downward volatility in price. However, there is also another, equally important, part to Satoshi's grand experiment: the concept of a proof of work-based blockchain to allow for public agreement on the order of transactions. Bitcoin as an application can be described as a first-to-file system: if one entity has 50 BTC, and simultaneously sends the same 50 BTC to A and to B, only the transaction that gets confirmed first will process. There is no intrinsic way of determining from two transactions which came earlier, and for decades this stymied the development of decentralized digital currency. Satoshi's blockchain was the first credible decentralized solution. And now, attention is rapidly starting to shift toward this second part of Bitcoin's technology, and how the blockchain concept can be used for more than just money. Commonly cited applications include using on-blockchain digital assets to represent custom currencies and financial instruments ("colored coins"), the ownership of an underlying physical device ("smart property"), non-fungible assets such as domain names ("Namecoin") as well as more advanced applications such as decentralized exchange, financial derivatives, peer-to-peer gambling and on-blockchain identity and reputation systems. Another important area of inquiry is "smart contracts" - systems which automatically move digital assets according to arbitrary pre-specified rules. For example, one might have a treasury contract of the form "A can withdraw up to X currency units per day, B can withdraw up to Y per day, A and B together can withdraw anything, and A can shut off B's ability to withdraw". The logical extension of this is decentralized autonomous organizations (DAOs) - long-term smart contracts that contain the assets and encode the bylaws of an entire organization. What Ethereum intends to provide is a blockchain with a built-in fully fledged Turing-complete programming language that can be used to create "contracts" that can be used to encode arbitrary state transition functions, allowing users to create any of the systems described above, as well as many others that we have not yet imagined, simply by writing up the logic in a few lines of code.

The ripple protocol: Executive summary for financial institutions

Ripple Labs is a technology company founded in 2012, financed by leading investors (Andreessen Horowitz, Google Ventures, IDG, etc.), and comprised of employees with experience in finance, payments, security, technology, and policy (Google, Goldman Sachs, Microsoft, E-Loan, Promontory Financial Group, US Federal Reserve, Square, Visa, etc.).

Ripple Gateways

A Ripple gateway is a business that provides onboard and offboard ramps to the Ripple network. Ripple is free open source software and no agreement with Ripple Labs is necessary. However, Ripple Labs would like to be of assistance in integration planning and implementation. This is a primer on considerations related to integration of the gateway service.

BlackCoin's Proof-of-Stake Protocol v2

The current Proof of Stake protocol has several potential security issues: coin age can be abused by malicious nodes to gain significant network weight to perform a successful double spend. Additionally, due to coin age, honest nodes can abuse the system by staking only on a periodical basis. This does not secure the network. Lastly: in the current system all components of a stake of proof are predictable enough to allow pre-computation of future proof-of-stakes. In this paper a system is proposed to solve said issues.

Zerocash: Decentralized Anonymous Payments from Bitcoin

Bitcoin is the first digital currency to see widespread adoption. While payments are conducted between pseudonyms, Bitcoin cannot offer strong privacy guarantees: payment transactions are recorded in a public decentralized ledger, from which much information can be deduced. Zerocoin(Miers et al., IEEE S&P 2013) tackles some of these privacy issues by unlinking transactions from the payment's origin. Yet, it still reveals payments' destinations and amounts, and is limited in functionality. In this paper, we construct a full-fledged ledger-based digital currency with strong privacy guarantees. Our results leverage recent advances in zero-knowledge Succinct Non-interactive ARguments of Knowledge (zk-SNARKs). First, we formulate and construct decentralized anonymous payment schemes (DAP schemes). A DAP scheme enables users to directly pay each other privately: the corresponding transaction hides the payment's origin, destination, and transferred amount. We provide formal definitions and proofs of the construction's security.Second, we build Zerocash, a practical instantiation of our DAP scheme construction. In Zerocash, transactions are less than 1 kB and take under 6 ms to verify -- orders of magnitude >more efficient than the less-anonymous Zerocoin and competitive with plain Bitcoin.

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Analysis of the Cryptocurrency Marketplace

This paper will go over the technical, economic, and social impact of cryptocurrencies such as Bitcoin and Litecoin. This document will go into a comprehensive level of detail about cryptocurrency technologies and protocols, as this is required to familiarize the reader with the principles behind the rapidly emerging open source economic ecosystem. Furthermore, emerging attack vectors of cryptocurrencies will be discussed, such as custom malware campaigns and targeted exploitation.

Zerocoin: Anonymous Distributed E-Cash from Bitcoin

Bitcoin is the first e-cash system to see widespread adoption. While Bitcoin offers the potential for new types of financial interaction, it has significant limitations regarding privacy. Specifically, because the Bitcoin transaction log is completely public, users’ privacy is protected only through the use of pseudonyms. In this paper we propose Zerocoin, a cryptographic extension to Bitcoin that augments the protocol to allow for fully anonymous currency transactions. Our system uses standard cryptographic assumptions and does not introduce new trusted parties or otherwise change the security model of Bitcoin. We detail Zerocoin’s cryptographic construction, its integration into Bitcoin, and examine its performance both in terms of computation and impact on the Bitcoin protocol.