Equihash
Equihash is a memory-hard Proof-of-work algorithm introduced by the University of Luxembourg's Interdisciplinary Centre for Security, Reliability and Trust (SnT) at the 2016 Network and Distributed System Security Symposium. The algorithm is based on a generalization of the Birthday problem which finds colliding hash values. It has severe time-space trade-offs but concedes vulnerability to unforeseen parallel optimizations. It was designed such that parallel implementations are bottle-necked by memory bandwidth in an attempt to worsen the cost-performance trade-offs of designing custom ASIC implementations. ASIC resistance in Equihash is based on the assumption that commercially-sold hardware already has quite high memory bandwidth, so improvements made by custom hardware may not be worth the development cost. General Equihash was proposed by Alex Biryukov and Dmitry Khovratovich as part of the University of Luxembourg research group CryptoLUX. It was introduced at the Network and Di ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Dmitry Khovratovich
Dmitry Khovratovich is a cryptographer, currently a Lead Cryptographer for the Dusk Network, researcher for the Ethereum Foundation, and member of the International Association for Cryptologic Research. He developed, together with Alex Biryukov, the Equihash proof-of-work algorithm which is currently being used as consensus mechanism for the Zcash cryptocurrency, and the Argon2 key derivation function, which won the Password Hashing Competition in July 2015. He is the publisher of several cryptanalysis papers for a number of mainstream cyphers, such as the first cryptanalytic attack on full-round AES-192 and AES-256 which is faster than a brute-force attack, an attack on the RadioGatún cryptographic primitive, and also the current best cryptanalysis on Skein, a candidate for the SHA-3 competition. In 2014, he published a research about the deanonymisation of clients in the Bitcoin P2P network Selected publications * Egalitarian computing, USENIX 2016, with Alex Biryuk ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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BitcoinGold
Bitcoin Gold (BTG) is a cryptocurrency. It is a hard fork of Bitcoin, the open source cryptocurrency. It is an open source, decentralized digital currency without a central bank or intermediary that can be sent from user to user on the peer-to-peer Bitcoin Gold network. The stated purpose of the hard fork is to change the proof of work algorithm so that ASICs ( Application-Specific Integrated Circuits) which are used to mine Bitcoin cannot be used to mine the Bitcoin Gold blockchain in the hopes that enabling mining on commonly available graphics cards will democratize and decentralize the mining and distribution of the cryptocurrency. The project began as a community-driven effort with six co-founders, half of whom continue to serve on the project's Board (including Lead Developer, Hang Yin.) History Bitcoin Gold hard forked from the Bitcoin Bitcoin ( abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Proof-of-work
Proof of work (PoW) is a form of cryptographic proof in which one party (the ''prover'') proves to others (the ''verifiers'') that a certain amount of a specific computational effort has been expended. Verifiers can subsequently confirm this expenditure with minimal effort on their part. The concept was invented by Moni Naor and Cynthia Dwork in 1993 as a way to deter denial-of-service attacks and other service abuses such as spam on a network by requiring some work from a service requester, usually meaning processing time by a computer. The term "proof of work" was first coined and formalized in a 1999 paper by Markus Jakobsson and Ari Juels. Proof of work was later popularized by Bitcoin as a foundation for consensus in a permissionless decentralized network, in which miners compete to append blocks and mint new currency, each miner experiencing a success probability proportional to the computational effort expended. PoW and PoS (proof of stake) remain the two best known S ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Application-specific Integrated Circuit
An application-specific integrated circuit (ASIC ) is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use, such as a chip designed to run in a digital voice recorder or a high-efficiency video codec. Application-specific standard product (ASSP) chips are intermediate between ASICs and industry standard integrated circuits like the 7400 series or the 4000 series. ASIC chips are typically fabricated using metal-oxide-semiconductor (MOS) technology, as MOS integrated circuit chips. As feature sizes have shrunk and design tools improved over the years, the maximum complexity (and hence functionality) possible in an ASIC has grown from 5,000 logic gates to over 100 million. Modern ASICs often include entire microprocessors, memory blocks including ROM, RAM, EEPROM, flash memory and other large building blocks. Such an ASIC is often termed a SoC (system-on-chip). Designers of digital ASICs often use a hardware descrip ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Proof Of Stake
Proof-of-stake (PoS) protocols are a class of consensus mechanisms for blockchains that work by selecting validators in proportion to their quantity of holdings in the associated cryptocurrency. This is done to avoid the computational cost of proof-of-work schemes. The first functioning use of PoS for cryptocurrency was Peercoin in 2012. Description For a blockchain transaction to be recognized, it must be appended to the blockchain. In the proof of stake blockchain the appending entities are named ''minters'' or (in the proof of work blockchains this task is carried out by the miners); in most protocols, the validators receive a reward for doing so. For the blockchain to remain secure, it must have a mechanism to prevent a malicious user or group from taking over a majority of validation. PoS accomplishes this by requiring that validators have some quantity of blockchain tokens, requiring potential attackers to acquire a large fraction of the tokens on the blockchain to mou ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cryptographic Hash Function
A cryptographic hash function (CHF) is a hash algorithm (a map of an arbitrary binary string to a binary string with fixed size of n bits) that has special properties desirable for cryptography: * the probability of a particular n-bit output result (hash value) for a random input string ("message") is 2^ (like for any good hash), so the hash value can be used as a representative of the message; * finding an input string that matches a given hash value (a ''pre-image'') is unfeasible, unless the value is selected from a known pre-calculated dictionary (" rainbow table"). The ''resistance'' to such search is quantified as security strength, a cryptographic hash with n bits of hash value is expected to have a ''preimage resistance'' strength of n bits. A ''second preimage'' resistance strength, with the same expectations, refers to a similar problem of finding a second message that matches the given hash value when one message is already known; * finding any pair of different messa ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bitmain
Bitmain Technologies Ltd., is a privately owned company headquartered in Beijing, China, that designs application-specific integrated circuit (ASIC) chips for bitcoin mining. History It was founded by Micree Zhan and Jihan Wu in 2013. Prior to founding Bitmain, Zhan was running DivaIP, a startup that allowed users to stream television to a computer screen via a set-top box, and Wu was a financial analyst and private equity fund manager. By 2018 it had become the world's largest designer of application-specific integrated circuit (ASIC) chips for bitcoin mining. The company also operates BTC.com and Antpool, historically two of the largest mining pools for bitcoin. In an effort to boost Bitcoin Cash (BCH) prices, Antpool "burned" 12% of the BCH they mined by sending them to irrecoverable addresses. Bitmain was reportedly profitable in early 2018, with a net profit of $742.7 million in the first half of 2018, and negative operating cash flow. TechCrunch reported that unsold inv ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pirate Chain
Piracy is an act of robbery or criminal violence by ship or boat-borne attackers upon another ship or a coastal area, typically with the goal of stealing cargo and other valuable goods. Those who conduct acts of piracy are called pirates, vessels used for piracy are pirate ships. The earliest documented instances of piracy were in the 14th century BC, when the Sea Peoples, a group of ocean raiders, attacked the ships of the Aegean and Mediterranean civilisations. Narrow channels which funnel shipping into predictable routes have long created opportunities for piracy, as well as for privateering and commerce raiding. Historic examples include the waters of Gibraltar, the Strait of Malacca, Madagascar, the Gulf of Aden, and the English Channel, whose geographic structures facilitated pirate attacks. The term ''piracy'' generally refers to maritime piracy, although the term has been generalized to refer to acts committed on land, in the air, on computer networks, and (i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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University Of Luxembourg
The University of Luxembourg ( French: ''Université du Luxembourg''; German: ''Universität Luxemburg''; Luxembourgish: ''Universitéit Lëtzebuerg'') is a public research university in Luxembourg. History The University of Luxembourg was founded in 2003 by combining four existing education and research institutes: the Centre universitaire, Institut supérieur d'études et de recherches pédagogiques, Institut supérieur de technologie, and Institut d'études éducatives et sociales. The university is the only public university in Luxembourg. Description The university has three campuses: the Belval Campus, the Kirchberg Campus, and the Limpertsberg Campus. The university is governed by a board of governors, a rector, and a university council. The current rector of the University of Luxembourg is Stéphane Pallage. Academics The university offers fourteen bachelor's degrees, forty-two master's degrees, and doctorates. Bachelor's degrees require a semester abroad. The u ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Blockchain
A blockchain is a type of distributed ledger technology (DLT) that consists of growing lists of records, called ''blocks'', that are securely linked together using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree, where data nodes are represented by leaves). The timestamp proves that the transaction data existed when the block was created. Since each block contains information about the previous block, they effectively form a ''chain'' (compare linked list data structure), with each additional block linking to the ones before it. Consequently, blockchain transactions are irreversible in that, once they are recorded, the data in any given block cannot be altered retroactively without altering all subsequent blocks. Blockchains are typically managed by a peer-to-peer, peer-to-peer (P2P) computer network for use as a public distributed ledger, where nodes collectively adhere to ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |