Cryptocurrency

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A crypto currency (or cryptocurrency) is a medium of exchange using cryptography to secure the transactions and to control the creation of new units.[1] The first crypto currency to be created was Bitcoin in 2009. Since then, numerous crypto currencies have been created.

Overview[edit]

Crypto currency is produced by the entire crypto currency system collectively, at a rate which is prior defined and publicly known. In centralized banking and economic systems such as the Federal Reserve System, governments control the value of currency by printing units of fiat money or demanding additions to digital banking ledgers. However, governments cannot produce units of crypto currency and as such, governments cannot provide backing for firms, banks or corporate entities which hold asset value measured in a decentralized crypto currency. The underlying technical system upon which all crypto currencies are now based was created by the group or individual known as Satoshi Nakamoto.[2][3][4]

Hundreds of crypto currency specifications now exist; most are similar to and derived from the first fully implemented crypto currency, Bitcoin.[5][6] Similar protocols include Proof-of-stake, a common authentication protocol forked from the Proof-of-work authentication protocol used by Bitcoin. Within crypto currency systems the safety, integrity and balance of all ledgers is maintained by a community of mutually distrustful parties referred to as miners: members of the general public who allow their idle computers to help validate and process transactions.[citation needed]

The underlying security of crypto currency systems comes from the difficulty of finding hash set intersections a task which generally takes a computer O(2^n/2) number of iterations to complete where n is the hash functions output size in bits. Bitcoins hashing function, 'SHA-2' has an output size of 512 bits, therefore a collision would take O(2^256) iterations to find -- a little less than one thousandth the number of atoms in the observable universe (~2^266). A type of crypto currency security subversion far more likely to succeed is the so-called "51%" attack; in this scenario an extremely powerful attacker attempts to take control of the global block-chain ledger by generating an alternate block-chain faster than the honest-one being produced by all other miners, this attack is very expensive and ineffective as payee wallet-nodes are not going to accept references to invalid transactions as payment, and honest Mining-nodes will never accept a block containing them, An attacker using the "51%" technique can only hope to undo one of his own transactions.[7]

Most crypto currencies are designed to gradually decrease production of currency, placing an ultimate cap on the total amount of currency that will ever be in circulation. This can mimic the scarcity (and value) of precious metals and avoid hyperinflation.[1][8] Compared with ordinary currencies held by financial institutions or kept as cash on hand, crypto currencies are less susceptible to seizure by law enforcement.[1][9][not in citation given] Existing crypto currencies are all pseudo-anonymous, though additions such as Zerocoin and its distributed laundry[10] feature have been suggested, which would allow for anonymity.[11][12][13]

History[edit]

The first crypto currency, Bitcoin, was created in 2009 by pseudonymous developer Satoshi Nakamoto. It used SHA-256, a cryptographic hash function, as its proof-of-work scheme.[14][15][16] In April 2011, Namecoin was created as an attempt at forming a decentralized DNS, which would make internet censorship very difficult. Soon after, in October 2011, Litecoin was released. It was the first successful cryptocurrency to use scrypt as its hash function instead of SHA-256. Another notable crypto currency, Peercoin was the first to use a proof-of-work/proof-of-stake hybrid.[17] Many other crypto currencies have been created though few have been successful, as they have brought little in the way of technical innovation. On 6 August 2014, the UK announced its Treasury had been commissioned to do a study of crypto currencies, and what role, if any, they can play in the UK economy. The study was also to report on whether regulation should be considered.[18]

Publicity[edit]

Central bank representatives have stated that the adoption of crypto currencies such as Bitcoin pose a significant challenge to central banks' ability to influence the price of credit for the whole economy, they've also stated that as trade using Crypto currencies become more popular, there is bound to be a loss of consumer confidence in fiat currencies. Gareth Murphy, a senior central banking officer has stated "widespread use [of crypto currency] would also make it more difficult for statistical agencies to gather data on economic activity, which are used by governments to steer the economy". He cautioned that virtual currencies pose a new challenge to central banks' control over the important functions of monetary and exchange rate policy.[19]

Jordan Kelley, founder of Robocoin launched the first Bitcoin ATM in the United States on February 20, 2014. The kiosk installed in Austin, Texas is similar to bank ATMs but has scanners to read government-issued identification such as a driver's license or a passport to confirm users' identities.[20]

The Dogecoin Foundation, a charitable organization centered around Dogecoin and co-founded by Dogecoin co-creator Jackson Palmer, donated more than $30,000 worth of Dogecoin to help fund the Jamaican bobsled team's trip to the 2014 Olympic games in Sochi, Russia.[21] The growing community around Dogecoin is looking to cement its charitable credentials by raising funds to sponsor service dogs for children with special needs.[22]

Legality[edit]

Crypto currencies are legal in all countries except Iceland, due primarily to Iceland's freeze on foreign exchange.[23] Controversy over the misuse of crypto currency has also led to restrictions in certain countries – regulators in China banned the handling of Bitcoins by financial institutions during an extremely fast adoption period in early 2014.[24] In Russia, though crypto currencies are perfectly legal, it is illegal to actually purchase goods with any currency other than the Russian ruble.[25]

On March 25, 2014 the IRS ruled that Bitcoin will be treated as property for tax purposes as opposed to currency. This means Bitcoin will be subject to capital gains tax. One benefit of this ruling is that it clarifies the legality of Bitcoin. No longer do investors need to worry that investments in or profit made from Bitcoins are illegal or how to report them to the IRS.[26]

Some crypto currency have legal issues such as Coinye, an altcoin that used, without permission, rapper Kanye West as its logo. This altcoin has been compared to the popular Dogecoin. Upon hearing of the release of Coinye, originally called Coinye West, attorneys for Kanye West sent a cease and desist letter to the email operator of Coinye, whose name remains unknown. The letter stated that Coinye was willful trademark infringement, unfair competition, cyberpiracy, and dilution and instructed Coinye to stop using the likeness and name of Kanye West.[27]

Arrests[edit]

There have been very few arrests in the United States related to Bitcoin. This is primarily due to the difficulty of tracking Bitcoin payments. The arrests that have been made are all on charges of using Bitcoin to launder money. The most notable case was the arrest of Charlie Shrem, the CEO of BitInstant, a Bitcoin exchange backed by the Winklevoss twins.[28]

Florida has taken a firm stance against money laundering through Bitcoin with its recent arrest of three money launderers. The launderers were purportedly using the website localbitcoins.com to launder hundreds of thousands of dollars worth in Bitcoin. They were apprehended after an undercover agent asked to purchase Bitcoin with the intent of buying stolen credit cards online.[29]

Though not directly related to crypto currency, Ross Ulbricht was arrested in October 2013 for running an illegal drug trafficking website, The Silk Road, that used Bitcoin as the only payment option. Ross William Ulbricht was arrested on charges of alleged murder-for-hire and narcotics trafficking violations and identified as the founder and chief operator "Dread Pirate Roberts." Bitcoins are the only currency accepted on the site, because they are traded electronically and are difficult to trace to individuals. But Bitcoin accounts also lack protections that most bank accounts have, including government-backed insurance.[30][31]

Fraud[edit]

On August 6, 2013 Magistrate Judge Amos Mazzant of the Eastern District of Texas federal court ruled that because crypto currency (expressly Bitcoin) can be used as money (it can be used to purchase goods and services, pay for individual living expenses, and exchanged for conventional currencies), it is a currency or form of money. This ruling allowed for the SEC to have jurisdiction over cases of securities fraud involving cryptocurrency.[32]

GBL, a Chinese Bitcoin trading platform suddenly shut down, and up to $5 million worth of Bitcoin disappeared with it.[33] Subscribers were unable to log into the Chinese bitcoin platform on October 26, 2013 and as much as $5 million disappeared.

In February 2014 crypto currency made national headlines due to the world's largest Bitcoin exchange, Mt. Gox, declaring bankruptcy. The company stated that it had lost nearly $473 million of their customer's Bitcoins likely due to theft. This was equivalent to approximately 750,000 Bitcoin, or about 7% of all the Bitcoins in existence. Due to this crisis, the price of a Bitcoin fell from a high of about $1,160 in December to under $400 in February.[34]

Timestamping[edit]

To not need a trusted third party to timestamp transactions added to the block chain ledger crypto currencies use various timestaping schemes.

Proof-of-work schemes[edit]

The first timestamping scheme invented was the proof-of-work scheme. The most widely used proof-of-work schemes are SHA-256, which was introduced by Bitcoin, and scrypt, which is used by currencies such as Litecoin.[17] The latter now dominates over the world of crypto currencies, with at least 480 confirmed implementations.[35]

Some other hashing algorithms that are used for proof-of-work include Blake-256, CryptoNight,[36] HEFTY1, Quark, SHA-3 (Keccak), scrypt-jane, scrypt-n, X11, and X13.

Proof-of-stake and combined schemes[edit]

Some crypto currencies, such as Peercoin, use a combined proof-of-work/proof-of-stake scheme,[17][37] while others such as Nxt[38] exclusively use proof-of-stake.

List of crypto currencies[edit]

This is a list of crypto currencies. By May 2014 there were more than 275 crypto currencies available for trade in online markets.[39]

Release Currency Symbol Founder Hash Algorithm Timestamping Website
2009 Bitcoin[nt 1] BTC[40][41] Satoshi Nakamoto[nt 2][42] SHA-256d[43][44] POW[44][45] bitcoin.org
2011 Namecoin[nt 3] NMC Vincent Durham[46][47] SHA-256 POS N/A
2011[44] Litecoin[nt 4] LTC Charles Lee[42] scrypt[44] POW litecoin.org[44]
2012[44] Peercoin PPC Sunny King
(pseudonym)[48]
SHA-256[49] POW & POS peercoin.net[44]
2013 Ripple[nt 5][50][51][52] XRP[52] Chris Larsen &
Jed McCaleb[53]
ECDSA[54] "Consensus" ripple.com
2013 Mastercoin MSC J. R. Willett [55] SHA-256d[56] N/A mastercoin.org
2013 Primecoin XPM Sunny King
(pseudonym)[48]
1CC/2CC/TWN[57] POW[57] primecoin.org
2013 Dogecoin[nt 6] DOGE Jackson Palmer
& Billy Markus[58]
scrypt[59] POW dogecoin.com
2014[60] Darkcoin[nt 7] DRK Evan Duffield &
Kyle Hagan[61]
X11 POW & POS[nt 8] darkcoin.io
2014 Auroracoin AUR Baldur Odinsson
(pseudonym)[62]
scrypt POW auroracoin.org

Notes[edit]

  1. ^ The first widely known decentralized ledger currency.
  2. ^ It is not known whether the name "Satoshi Nakamoto" is real or a pseudonym, or whether it represents one person or a group of people.
  3. ^ A crypto currency that also acts as an alternative, decentralized DNS.
  4. ^ The first successful scrypt crypto currency.
  5. ^ A unique crypto currency based on peer to peer debt transfer. The term Ripple can also refer to both the digital currency (also known as XRP), or to the payment network on which it and other digital currencies can be traded.
  6. ^ A crypto currency to be based on an internet meme.
  7. ^ A crypto currency that adds privacy to transactions through a system called Darksend, an implementation of CoinJoin.
  8. ^ Via Masternodes containing 1000 DRK as "Proof of Service". Through an automated voting mechanism, one Masternode is selected per block and receives 20% of mining rewards.

Criticism[edit]

  • Some have expressed concern that cryptocurrencies are extremely risky due to their very high volatility[63] and potential for pump and dump schemes[64]
  • Some cryptocurrency systems are pre-mined, have hidden launches, or have extreme rewards for the first miners.[65][better source needed] Pre-mining means currency is generated by the currency's founders prior to mining code being released to the public.[66] It often refers to a deceptive practice, but can also be used as an inherent part of a digital cryptocurrency's design, as in the case of Ripple or Nxt.[67]
  • Most cryptocurrencies are duplicates of existing cryptocurrencies with minor changes and no novel technical developments. One such, "Coinye West", a comedy cryptocurrency alluding to the rapper Kanye West, was served a cease-and-desist letter on January 7, 2014.[68]
  • Very few cryptocurrencies can be exchanged for fiat currencies and instead can only be traded for other cryptocurrencies. Banks generally do not offer services for them and sometimes refuse to offer services to virtual-currency companies.[69]
  • There are ways to permanently lose cryptocurrency “from local storage due to malware or data loss. This can also happen through the destruction of the physical media, effectively removing lost cryptocurrencies forever from their markets.[70]
  • There are many perceived criteria that cryptocurrencies must reach before they can become a mainstream currency. Because cryptocurrencies do not fully meet some features of fiat currency, few merchants accept them, weakening the value of cryptocurrency.[71]
  • With technological advancement in some cryptocurrencies, there has risen a too high of cost of entry for a casual miner (one who “mines” or produces cryptocurrency coins through specialized hardware and software).[72]
  • Cryptocurrency transactions are irreversible. One of the features cryptocurrency lacks in comparison to conventional methods of payment is consumer protection against fraud, such as chargebacks to credit cards.[73]
  • Some coins may be a project with little to no community backing and no visible developer.[74]
  • While cryptocurrencies are digital currencies that are managed through advanced encryption techniques, many governments have taken a cautious approach toward them, fearing their lack of central control and the effects they could have on financial security.[75]
  • Environmentally conscious people are concerned with the enormous amount of energy that goes into mining cryptocurrency with little to show in return.[76]
  • Traditional financial products have strong consumer protections. However, if Bitcoins are lost or stolen, there is no intermediary with the power to limit consumer losses.[77]
  • Regulators in several countries have warned against their use and some have taken concrete regulatory measures to dissuade users.[78]

See also[edit]

References[edit]

  1. ^ a b c Andy Greenberg (20 April 2011). "Crypto Currency". Forbes.com. Retrieved 8 August 2014. 
  2. ^ Bitcoin-block-signing History, http://blockchain.info, 2 March 2014
  3. ^ Deflation and Banking, http://www.econlib.org, 19 December 2006
  4. ^ Bitcoin Creation Mechanism, https://en.bitcoin.it, 12 January 2014
  5. ^ Listing of active coins, http://cryptocoincharts.info, 27 February 2014
  6. ^ another authentication protocol forked from P.O.S., https://en.bitcoin.it, 7 June 2013
  7. ^ 'Hashing' Complexity, ucdavis.edu, 12 February 2014
  8. ^ How Cryptocurrencies Could Upend Banks' Monetary Role, American Banker, 26 May 2013
  9. ^ The FBI's Plan For The Millions Worth Of Bitcoins Seized From Silk Road, Forbes, 4 October 2013
  10. ^ "Zerocoin - Making bitcoin anonymous". cryptographyengineering.com. 2013. Retrieved 2 June 2014. 
  11. ^ 'Zerocoin' Add-on For Bitcoin Could Make It Truly Anonymous And Untraceable, Forbes, 26 May 2013
  12. ^ Matthew Green (26 May 2013). "Zerocoin: Anonymous Distributed E-Cash from Bitcoin" (pdf). Johns Hopkins University. 
  13. ^ This is Huge: Gold 2.0 - Can code and competition build a better Bitcoin?, New Bitcoin World, 26 May 2013
  14. ^ BITCOIN A Primer for Policymakers, JERRY BRITO AND ANDREA CASTILLO, Mercatus Center, George Mason University, 31-08-2013
  15. ^ What is Bitcoin Mining?, The Genesis Block, 26 May 2013
  16. ^ Bitcoin developer chats about regulation, open source, and the elusive Satoshi Nakamoto, PCWorld, 26-05-2013
  17. ^ a b c Wary of Bitcoin? A guide to some other cryptocurrencies, ars technica, 26-05-2013
  18. ^ "UK launches initiative to explore potential of virtual currencies". The UK News. Retrieved 8 August 2014. 
  19. ^ decentralized currencies impact on central banks, rte News, 3 April 2014
  20. ^ First U.S. Bitcoin ATMs to open soon in Seattle, Austin, Reuters, 18 February 2014
  21. ^ Dogecoin Users Raise $30,000 to Send Jamaican Bobsled Team to Winter Olympics, Digital Trends, 20 January 2014
  22. ^ Dogecoin Community Raising $30,000 for Children's Charity, International Business Times, 4 February 2014
  23. ^ Controls suspend trading in Bitcoin, MBL.is, 19 December 2013
  24. ^ http://bitcoinmagazine.com/12839/big-picture-china-bitcoin/
  25. ^ Bitcoin's Legality Around The World, Forbes, 31 January 2014
  26. ^ 3 Reasons The IRS Bitcoin Ruling Is Good For Bitcoin, Nasdaq, 24 March 2014
  27. ^ Infringement of Kayne West Mark and Other Violations, Pryor Cashman LLP, 6 January 2014
  28. ^ TRACKING THE INTANGIBLE: HOW FRAUD EXAMINERS ARE BUSTING BITCOIN FRAUD, The Fraud Examiner, November 2013
  29. ^ Florida Targets High-Dollar Bitcoin Exchangers, Krebs on Security, February 2014
  30. ^ How the feds took down the Dread Pirate Roberts, ars technica, 2 October 2013
  31. ^ Drug site Silk Road wiped out by Bitcoin glitch, CNNMoney, 14 February 2014
  32. ^ SEC v Shavers, United States District Court Eastern District Of Texas, 08-06-2013
  33. ^ Vanishing Bitcoins: $5 million in crypto-currency lost down a Chinese memory hole, 21st Century Wire, 12-11-2013
  34. ^ Mt. Gox Seeks Bankruptcy After $480 Million Bitcoin Loss, Carter Dougherty and Grace Huang, Bloomberg News, Feb. 28, 2014
  35. ^ SCRYPT CRYPTOCOINS - CryptoCoinTalk
  36. ^ Equal Proof-of-Work, Cryptonote.org
  37. ^ "PPCoin: Peer-to-Peer Crypto-Currency with Proof-of-Stake". http://barkingshibes.com/wp-content/uploads/2014/02/ppcoin-paper.pdf, 19-08-2012. Sunny King, Scott Nadal. January 2014. Retrieved 12-05-2013. 
  38. ^ "NXTcrypto". NXTcrypto. Retrieved 5 March 2014. 
  39. ^ "Crypto-Currency Market Capitalizations". CoinMarketCap. May 13, 2014. Retrieved 2014-05-13. 
  40. ^ Dixon, Lance (24 December 2013). "Building Bitcoin use in South Florida and beyond". Miami Herald. Retrieved 24 January 2014. 
  41. ^ Spaven, Emily (3 December 2013). "Bitcoin price could reach $98,500, say Wall Street analysts". CoinDesk. Retrieved 24 January 2014. 
  42. ^ a b McMillan, Robert (30 August 2013). "Ex-Googler gives the world a better Bitcoin". Wired (Condé Nast). Retrieved 14 January 2014. 
  43. ^ Taylor, Michael Bedford (2013). "Bitcoin and the age of bespoke silicon" (PDF). Proceedings of the 2013 International Conference on Compilers, Architectures and Synthesis for Embedded Systems (Piscataway, NJ: IEEE Press). ISBN 978-1-4799-1400-5. Retrieved 14 January 2014. 
  44. ^ a b c d e f g Steadman, Ian (7 May 2013). "Wary of Bitcoin? A guide to some other crypto currencies". Wired UK (Condé Nast UK). 
  45. ^ Hobson, Dominic (2013). "What is Bitcoin?". XRDS: Crossroads, The ACM Magazine for Students 20 (1) (Association for Computing Machinery). pp. 40–44. doi:10.1145/2510124. ISSN 1528-4972. 
  46. ^ vinced/namecoin, GitHub
  47. ^ Keller, Levin (2011-03-19). "Namecoin - a distributed name system based on Bitcoin". Prezi. 
  48. ^ a b Boase, Richard (20 November 2013). "Litecoin spikes to $200m market capitalization in five hours". CoinDesk. Retrieved 14 January 2014. 
  49. ^ Bradbury, Danny (7 November 2013). "Third largest crypto currency peercoin moves into spotlight with Vault of Satoshi deal". CoinDesk. Retrieved 14 January 2014. 
  50. ^ Chayka, Kyle (2 July 2013). "What Comes After Bitcoin?". Pacific Standard. Retrieved 18 Jan 2014. 
  51. ^ Vega, Danny (4 December 2013). "Ripple's Big Move: Mining Crypto currency with a Purpose". Seattlepi.com (Hearst Seattle Media, LLC, a division of The Hearst Corporation). 
  52. ^ a b Brown, Ariella (17 May 2013). "10 things you need to know about Ripple". CoinDesk. Retrieved 15 January 2014. 
  53. ^ Simonite, Tom (11 April 2013). "Big-name investors back effort to build a better Bitcoin". MIT Technology Review. Retrieved 14 January 2014. 
  54. ^ "How it works - Ripple Wiki". Retrieved 20 January 2014. 
  55. ^ Buterin, Vitalik (4 November 2013). "Mastercoin: A Second-Generation Protocol on the Bitcoin Blockchain". Bitcoin Magazine. Retrieved 9 January 2014. 
  56. ^ "Mastercoin Spec". Retrieved 2 April 2014. 
  57. ^ a b "FAQ · primecoin/primecoin Wiki · GitHub". Retrieved 20 January 2014. 
  58. ^ Chang, Jon M (27 December 2013). "Bitcoin alternative 'Dogecoin' hacked, 21 million coins stolen". ABC News (website) (ABC News Internet Ventures, Yahoo! – ABC News Network). Retrieved 14 January 2014. 
  59. ^ "Intro - Dogecoin # Technical specifications". Retrieved 14 December 2013. 
  60. ^ https://bitcointalk.org/index.php?topic=421615.0
  61. ^ Scharr, Jill (28 May 2014). "What is Darkcoin? An FAQ". Tom's Guide. 
  62. ^ Casey, Michael J. (2014-03-05). "Auroracoin already third-biggest cryptocoin–and it's not even out yet". The Wall Street Journal. 
  63. ^ "Bitcoin's Volatility Problem: Why Today's Selloff Won't Be the Last". Businessweek. 5 December 2013. Retrieved 29 December 2013. 
  64. ^ "A crypto-currency primer: Bitcoin vs. Litecoin". ZDNet. 14 December 2013. Retrieved 29 December 2013. 
  65. ^ "Scamcoins". August 2013. 
  66. ^ Morris, David Z (24 December 2013). "Beyond bitcoin: Inside the cryptocurrency ecosystem". CNNMoney, a service of CNN, Fortune & Money (Cable News Network). Retrieved 11 January 2014. 
  67. ^ Bradbury, Danny (25 June 2013). "Bitcoin's successors: from Litecoin to Freicoin and onwards". The Guardian (Guardian News and Media Limited). Retrieved 11 January 2014. 
  68. ^ http://arstechnica.com/business/2014/01/kanye-wests-lawyer-orders-coinye-to-cease-and-desist-just-before-launch/
  69. ^ Sidel, Robin (22 December 2013). "Banks Mostly Avoid Providing Bitcoin Services. Lenders Don't Share Investors' Enthusiasm for the Virtual-Currency Craze". Online.wsj.com. Retrieved 29 December 2013. 
  70. ^ Keeping Your Cryptocurrency Safe, Center for a Stateless Society, 1 April 2014
  71. ^ The Future of Cryptocurrency, Investopedia, 10 September 2013
  72. ^ Want to make money off Bitcoin mining? Hint: Don't mine, The Week, 15 April 2013
  73. ^ About Bitcoin, Cryptocurrency.org, 19 May 2013
  74. ^ Fundamental Analysis for Cryptocurrency, Wall Street Crypto, 10 January 2014
  75. ^ Cryptocurrency and Global Financial Security Panel at Georgetown Diplomacy Conf, MeetUp, 11 April 2014
  76. ^ Experiments in Cryptocurrency Sustainability, Let's Talk Bitcoin, March 2014
  77. ^ Four Reasons You Shouldn't Buy Bitcoins, Forbes, 3 April 2013
  78. ^ Schwartzkopff, Frances (17 December 2013). "Bitcoins Spark Regulatory Crackdown as Denmark Drafts Rules". Bloomberg. Retrieved 29 December 2013. 

External links[edit]