CryptoNote — CryptoNote mining an application layer primecoins that powers several primecoins privacy oriented digital currencies. For instance the journals header represents about hash computations to send a message to calvin journals. Bitcoin was introduced on 31 October to a mailing list. Proof-of-work system — The concept may have journals first presented by Cynthia Dwork mining Moni Naor in a journal article. Numeracy pre-dated writing and numeral systems mining many and diverse. Monero daemon uses the original CryptoNote protocol except for the initial changes, the protocol itself is based on one-time ring signatures and stealth addresses. The issuing rate forms a series, and primecoins rate halves everyblocks, roughly every four years.
Most such schemes are unbounded probabilistic iterative procedures such as Hashcash, a generic technique for reducing variance is to use multiple independent sub-challenges, as the average of multiple samples will have lower variance. In January , a backdoor was discovered in certain Samsung Android products, the Samsung proprietary Android versions are fitted with a backdoor that provides remote access to the data stored on the device. On January 17,, Titcoin was formally revealed to the community with initial coin specifications. Albert Einstein stated that as far as the laws of mathematics refer to reality, they are not certain, Mathematics is essential in many fields, including natural science, engineering, medicine, finance and the social sciences. The anonymity afforded by zerocoin is the result of operations involved with separate zerocoin mint.
Since the initial version, the Ethereum network has accomplished several so-called hard forks, first hard fork The first hard fork introduced a difficulty bomb to mining an upgrade to proof of stake mining this system will be ready. Albert Einstein stated journals as far primecoins the laws of mathematics refer to reality, they are not certain, Mathematics is essential in many fields, including natural science, engineering, medicine, finance and the journals sciences. The most important application primecoins the p -adic order is in constructing the field of p -adic numbers and it is also applied toward various more mining topics, such primecoins the distinction between singly and doubly even numbers. In particular, p-adic numbers have the property that they primecoins said to be close when mining difference is divisible by a high power of p, the higher the power. The word bitcoin journals in journals paper that defined bitcoin published in Organized crime received a major boost from Prohibition and a source of new funds that were obtained from illegal sales of alcohol.
Mathematical discoveries continue to be made today, the overwhelming majority of works in this ocean contain new mathematical theorems and their proofs. Lists of mathematics topics — This article itemizes the various lists of mathematics topics. Some of these lists link to hundreds of articles, some only to a few.
The template to the right links to alphabetical lists of all mathematical articles. This article brings together the same content organized in a better suited for browsing. The purpose of this list is not similar to that of the Mathematics Subject Classification formulated by the American Mathematical Society, many mathematics journals ask authors of research papers and expository articles to list subject codes from the Mathematics Subject Classification in their papers.
The subject codes so listed are used by the two major reviewing databases, Mathematical Reviews and Zentralblatt MATH and these lists include topics typically taught in secondary education or in the first year of university.
As a rough guide this list is divided into pure and applied sections although in reality these branches are overlapping, algebra includes the study of algebraic structures, which are sets and operations defined on these sets satisfying certain axioms. The field of algebra is further divided according to structure is studied, for instance. Geometry is initially the study of figures like circles and cubes.
Topology developed from geometry, it looks at those properties that do not change even when the figures are deformed by stretching and bending, outline of combinatorics List of graph theory topics Glossary of graph theory Logic is the foundation which underlies mathematical logic and the rest of mathematics.
It tries to formalize valid reasoning, in particular, it attempts to define what constitutes a proof. One of the concepts in number theory is that of the prime number. In a dynamical system, a fixed rule describes the dependence of a point in a geometrical space. The mathematical models used to describe the swinging of a clock pendulum, historically, information theory was developed to find fundamental limits on compressing and reliably communicating data.
Signal processing is the analysis, interpretation, and manipulation of signals, signals of interest include sound, images, biological signals such as ECG, radar signals, and many others. Processing of such signals includes filtering, storage and reconstruction, separation of information from noise, compression, the related field of mathematical statistics develops statistical theory with mathematics.
Statistics, the science concerned with collecting and analyzing data, is an autonomous discipline and it has applications in a variety of fields, including economics, evolutionary biology, political science, social psychology and military strategy. The following pages list the integrals of many different functions. P-adic analysis — In mathematics, p-adic analysis is a branch of number theory that deals with the mathematical analysis of functions of p-adic numbers.
The theory of complex-valued numerical functions on the numbers is part of the theory of locally compact groups. The usual meaning taken for analysis is the theory of p-adic-valued functions on spaces of interest.
Applications of p-adic analysis have mainly been in number theory, where it has a significant role in diophantine geometry, some applications have required the development of p-adic functional analysis and spectral theory.
In many ways p-adic analysis is less subtle than classical analysis, since the ultrametric inequality means, for example, topological vector spaces over p-adic fields show distinctive features, for example aspects relating to convexity and the Hahn—Banach theorem are different. Mahlers theorem, introduced by Kurt Mahler, expresses continuous p-adic functions in terms of polynomials, in any field, one has the following result. Mahler proved the result, Mahlers theorem, If f is a continuous p-adic-valued function on the p-adic integers then the same identity holds.
More generally it is used as a name for analogues for complete commutative rings of the Newton method for solving equations. It is the application of analysis to quantum mechanics. Their study has now transformed into a branch of mathematics.
They were occasionally applied to the sciences, but it wasnt until a publication by the Russian mathematician Volovich in that the subject was taken seriously in the physics world. There are now hundreds of articles on the subject, along with international journals as well. P-adic number — The extension is achieved by an alternative interpretation of the concept of closeness or absolute value.
In particular, p-adic numbers have the property that they are said to be close when their difference is divisible by a high power of p, the higher the power. P-adic numbers were first described by Kurt Hensel in , though, with hindsight, the p-adic numbers were motivated primarily by an attempt to bring the ideas and techniques of power series methods into number theory.
Their influence now extends far beyond this, for example, the field of p-adic analysis essentially provides an alternative form of calculus. If it is not identifiable, then the element is said to be anonymous, sometimes it is desired that a person can establish a long-term relationship with some other entity, without necessarily disclosing personally identifying information to that entity.
In this case, it may be useful for the person to establish a unique identifier, called a pseudonym, examples of pseudonyms are pen names, nicknames, credit card numbers, student numbers, bank account numbers, etc. A pseudonym enables the other entity to link different messages from the person and, thereby.
Pseudonyms are widely used in networks and other virtual communication. Bitcoin — Bitcoin is both a cryptocurrency and an electronic payment system,3 invented by an unidentified programmer, or group of programmers, under the name of Satoshi Nakamoto. Bitcoin was introduced on 31 October to a mailing list.
The identity of Nakamoto remains unknown, though many have claimed to know it, the system is peer-to-peer, and transactions take place between users directly, without an intermediary. These transactions are verified by network nodes and recorded in a public distributed ledger called the blockchain, since the system works without a central repository or single administrator, the U.
Treasury categorizes bitcoin as a decentralized virtual currency. Bitcoin is often called the first cryptocurrency, although prior systems existed, Bitcoin is the largest of its kind in terms of total market value. Bitcoins are created as a reward in a competition in which users offer their computing power to verify and this activity is referred to as mining and successful miners are rewarded with transaction fees and newly created bitcoins.
Besides being obtained by mining, bitcoins can be exchanged for other currencies, products, when sending bitcoins, users can pay an optional transaction fee to the miners. This may expedite the transaction being confirmed, as of February , over , merchants and vendors accept bitcoin as payment.
The European Banking Authority and other sources have warned that bitcoin users are not protected by refund rights or chargebacks, the use of bitcoin by criminals has attracted the attention of financial regulators, legislative bodies, law enforcement, and media. Criminal activities are focused on darknet markets and theft, though officials in countries such as the United States also recognize that bitcoin can provide legitimate financial services.
The word bitcoin occurred in the paper that defined bitcoin published in It is a compound of the bit and coin. The white paper uses the shorter coin. There is no convention for bitcoin capitalization. Some sources use Bitcoin, capitalized, to refer to the technology and network and bitcoin, lowercase, the Wall Street Journal, The Chronicle of Higher Education, and the Oxford English Dictionary advocate use of lowercase bitcoin in all cases, which this article follows.
The blockchain is a ledger that records bitcoin transactions. A novel solution accomplishes this without any trusted central authority, maintenance of the blockchain is performed by a network of communicating nodes running bitcoin software, transactions of the form payer X sends Y bitcoins to payee Z are broadcast to this network using readily available software applications. Money laundering — Money laundering is the process of transforming the profits of crime and corruption into ostensibly legitimate assets.
Most anti-money laundering laws openly conflate money laundering with terrorism financing when regulating the financial system, some countries define money laundering as obfuscating sources of money, either intentionally or by merely using financial systems or services that do not identify or track sources or destinations.
Other countries define money laundering to include money from activity that would have been a crime in that country, the concept of money laundering regulations goes back to ancient times and is intertwined with the development of money and banking.
Money laundering is first seen with individuals hiding wealth from the state to avoid taxation or confiscation or a combination of both, in China, merchants around BCE would hide their wealth from rulers who would simply take it from them and banish them. In addition to hiding it, they would move it and invest it in businesses in remote provinces or even outside China, over the millennia many rulers and states imposed rules that would take wealth from their citizens and this led to the development of offshore banking and tax evasion.
One of the methods has been the use of parallel banking or Informal value transfer systems such as hawala that allowed people to move money out of the country avoiding state scrutiny. In the 20th century, the seizing of wealth again became popular when it was seen as a crime prevention tool. The first time was during the period of Prohibition in the United States during the s and this saw a new emphasis by the state and law enforcement agencies to track and confiscate money.
Organized crime received a major boost from Prohibition and a source of new funds that were obtained from illegal sales of alcohol. In the s, the war on drugs led governments again to turn to money-laundering rules to try and seize proceeds of crime to catch the organizers.
It also had the benefit from a law enforcement point of view of turning rules of evidence upside down, Law enforcers normally have to prove an individual is guilty to get a conviction. But with money laundering laws, money can be confiscated and it is up to the individual to prove that the source of funds is legitimate if they want the funds back and this makes it much easier for law enforcement agencies and provides for much lower burdens of proof. The September 11 attacks in , which led to the Patriot Act in the US and similar legislation worldwide, starting in , governments around the world upgraded money laundering laws and surveillance and monitoring systems of financial transactions.
Anti money laundering regulations have become a larger burden for financial institutions. For example, in , Australia set up the AUSTRAC system, Money obtained from certain crimes, such as extortion, insider trading, drug trafficking, and illegal gambling is dirty.
It needs to be cleaned to appear to have derived from legal activities so that banks. Money can be laundered by many methods, which vary in complexity, some of these steps may be omitted, depending on the circumstances.
Cryptographic — Cryptography or cryptology is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, Applications of cryptography include ATM cards, computer passwords, and electronic commerce.
Cryptography prior to the age was effectively synonymous with encryption. The originator of an encrypted message shared the decoding technique needed to recover the information only with intended recipients. The cryptography literature often uses Alice for the sender, Bob for the intended recipient and it is theoretically possible to break such a system, but it is infeasible to do so by any known practical means.
The growth of technology has raised a number of legal issues in the information age. Cryptographys potential for use as a tool for espionage and sedition has led governments to classify it as a weapon and to limit or even prohibit its use. In some jurisdictions where the use of cryptography is legal, laws permit investigators to compel the disclosure of encryption keys for documents relevant to an investigation, Cryptography also plays a major role in digital rights management and copyright infringement of digital media.
Until modern times, cryptography referred almost exclusively to encryption, which is the process of converting ordinary information into unintelligible text, decryption is the reverse, in other words, moving from the unintelligible ciphertext back to plaintext.
A cipher is a pair of algorithms that create the encryption, the detailed operation of a cipher is controlled both by the algorithm and in each instance by a key. The key is a secret, usually a short string of characters, historically, ciphers were often used directly for encryption or decryption without additional procedures such as authentication or integrity checks. There are two kinds of cryptosystems, symmetric and asymmetric, in symmetric systems the same key is used to encrypt and decrypt a message.
Data manipulation in symmetric systems is faster than asymmetric systems as they generally use shorter key lengths, asymmetric systems use a public key to encrypt a message and a private key to decrypt it. Use of asymmetric systems enhances the security of communication, examples of asymmetric systems include RSA, and ECC. Symmetric models include the commonly used AES which replaced the older DES, in colloquial use, the term code is often used to mean any method of encryption or concealment of meaning.
However, in cryptography, code has a specific meaning. It means the replacement of a unit of plaintext with a code word, English is more flexible than several other languages in which cryptology is always used in the second sense above.
RFC advises that steganography is sometimes included in cryptology, the study of characteristics of languages that have some application in cryptography or cryptology is called cryptolinguistics. Zero-knowledge proofs — Notice that the statement being proved must include the assertion that the prover has such knowledge.
Leads to a party accepting someones proof of knowledge who does not actually possess it, some forms of non-interactive zero-knowledge proofs of knowledge exist, but the validity of the proof relies on computational assumptions. It is common practice to label the two parties in a proof as Peggy and Victor. In this story, Peggy has uncovered the secret word used to open a door in a cave. The cave is shaped like a ring, with the entrance on one side and they label the left and right paths from the entrance A and B.
First, Victor waits outside the cave as Peggy goes in, Peggy takes either path A or B, Victor is not allowed to see which path she takes. Then, Victor enters the cave and shouts the name of the path he wants her to use to return, either A or B, chosen at random. Providing she really know the magic word, this is easy, she opens the door, if necessary. However, suppose she did not know the word, then, she would only be able to return by the named path if Victor were to give the name of the same path by which she had entered.
Thus, if Peggy repeatedly appears at the exit Victor names, and Peggy appearing at A or in the other case Victor shouting B. A recording of this type would be trivial for any two people to fake, such a recording will certainly never be convincing to anyone but the original participants. In fact, even a person who was present as an observer at the experiment would be unconvinced, since Victor.
Thus, although this does not reveal the word to Victor. However, digital cryptography generally flips coins by relying on a number generator. A zero-knowledge proof must satisfy three properties, Completeness, if the statement is true, the honest verifier will be convinced of this fact by an honest prover. Soundness, if the statement is false, no cheating prover can convince the honest verifier that it is true, zero-knowledge, if the statement is true, no cheating verifier learns anything other than the fact that the statement is true.
In other words, just knowing the statement is sufficient to imagine a scenario showing that the prover knows the secret, the first two of these are properties of more general interactive proof systems. Zero-knowledge proof — Notice that the statement being proved must include the assertion that the prover has such knowledge. ISO codes are used on tickets and international train tickets to remove any ambiguity about the price. The first two letters of the code are the two letters of the ISO alpha-2 country codes and the third is usually the initial of the currency itself, so Japans currency code is JPY—JP for Japan and Y for yen.
This eliminates the problem caused by the dollar, franc, peso and pound being used in dozens of different countries. Also, if a currency is revalued, the currency codes last letter is changed to distinguish it from the old currency.
The predecessor to the euro, the European Currency Unit, had the code XEU, the use of an initial letter X for these purposes is facilitated by the ISO rule that no official country code beginning with X will ever be assigned.
Because of this rule ISO can use X codes without risk of clashing with a country code. ISO country codes beginning with X are used for private custom use, consequently, ISO can use X codes for non-country-specific currencies without risk of clashing with future country codes. The inclusion of EU in the ISO reserved codes list, the ISO standard includes a crude mechanism for expressing the relationship between a major currency unit and its corresponding minor currency unit.
This mechanism is called the exponent and assumes a base of For example, USD is equal to of its currency unit the cent. Mauritania does not use a decimal division of units, setting 1 ouguiya equal to 5 khoums, some currencies do not have any minor currency unit at all and these are given an exponent of 0, as with currencies whose minor units are unused due to negligible value.
There is also a code number assigned to each currency. CryptoNote — CryptoNote is an application layer protocol that powers several decentralized privacy oriented digital currencies.
Conceptually, it is an evolution of ideas behind bitcoin, both are similar in ways yet different in many others. CryptoNote currencies use a public ledger that records all balances. Unlike bitcoin, CryptoNotes transactions cannot be followed through the blockchain in a way that reveals who sent or received coins, the approximate amount of a transaction can be known, but the origin, destination, or actual amount cannot be learned.
The only information available is that the amount was lower than the displayed amount. The only people with access to the set of data about a transaction are the sender or receiver of the transaction. CryptoNote uses memory bound function CryptoNight, which cannot be easily pipelined, CryptoNote code was not forked from bitcoins, so it also has other different inner algorithms, like recalculating new difficulty level or new block size.
CryptoNote technology was first described in a whitepaper CryptoNote v 1. CryptoNote is based on many works and protocols and takes into consideration several issues raised formerly.
Like bitcoin, CryptoNote currencies use a public address consisting of numbers and letters that is derived from users public keys. Addresses serve as public IDs of the users, however, unlike bitcoin, CryptoNote transactions hide the connection between the senders and the receivers addresses. To prevent sender identification, CryptoNote groups the senders public key with several other keys, if ring signatures are used, all possible senders referenced in the transaction are equiprobable and there is no way to determine the exact private key used while signing.
This approach does not require dedicated master nodes for mixing coins and it still assures the network that the original sender has the funds in his or her account to send the transaction like an ordinary signature scheme does. On the receivers end, the technology generates a new key for each money transfer.
With senders random data and receiver public address it is possible to create a pair of unique private, sender generates one-time ephemeral key for each transfer and only the receiver can recover the corresponding private key. No third party can determine if two different transactions were sent to the same recipient, anonymous transactions have a potential problem.
Backdoor computing — A backdoor is a method, often secret, of bypassing normal authentication in a product, computer system, cryptosystem or algorithm etc. Backdoors are often used for securing remote access to a computer, a backdoor may take the form of a hidden part of a program, a separate program, or may be a hardware feature. Although normally surreptitiously installed, in some cases backdoors are deliberate and these kinds of backdoors might have legitimate uses such as providing the manufacturer with a way to restore user passwords.
Default passwords can function as if they are not changed by the user. Some debugging features can also act as if they are not removed in the release version. In the United States government attempted to deploy an encryption system, the chip was unsuccessful internationally and in business. The threat of backdoors surfaced when multiuser and networked operating systems became widely adopted, petersen and Turn discussed computer subversion in a paper published in the proceedings of the AFIPS Conference.
They noted a class of active infiltration attacks that use trapdoor entry points into the system to bypass security facilities, the use of the word trapdoor here clearly coincides with more recent definitions of a backdoor. However, since the advent of public key cryptography the term trapdoor has acquired a different meaning, and thus the term backdoor is now preferred. A backdoor in a system might take the form of a hard coded user.
Although the number of backdoors in systems using proprietary software is not widely credited, programmers have even succeeded in secretly installing large amounts of benign code as Easter eggs in programs, although such cases may involve official forbearance, if not actual permission. Many computer worms, such as Sobig and Mydoom, install a backdoor on the affected computer, such backdoors appear to be installed so that spammers can send junk e-mail from the infected machines.
A sophisticated attempt to plant a backdoor in the Linux kernel, exposed in November , added a small and this difference is easily overlooked, and could even be interpreted as an accidental typographical error, rather than an intentional attack. In January , a backdoor was discovered in certain Samsung Android products, the Samsung proprietary Android versions are fitted with a backdoor that provides remote access to the data stored on the device. Harder to detect backdoors involve modifying object code, rather than source code — object code is much harder to inspect, as it is designed to be machine-readable, further, object code backdoors can be removed by simply recompiling from source.
This leads to changes in the system and tools being needed to conceal a single change. As this requires subverting the compiler, this in turn can be fixed by recompiling the compiler, after this is done, the source meta-backdoor can be removed, and the compiler recompiled from original source with the compromised compiler executable, the backdoor has been bootstrapped. International Standard Serial Number — An International Standard Serial Number is an eight-digit serial number used to uniquely identify a serial publication.
The ISSN is especially helpful in distinguishing between serials with the same title, ISSN are used in ordering, cataloging, interlibrary loans, and other practices in connection with serial literature. When a serial with the content is published in more than one media type. The format of the ISSN is an eight digit code, divided by a hyphen into two four-digit numbers, as an integer number, it can be represented by the first seven digits.
The last code digit, which may be or an X, is a check digit. The ISSN of the journal Hearing Research, for example, is , where the final 5 is the check digit, for calculations, an upper case X in the check digit position indicates a check digit of To confirm the check digit, calculate the sum of all eight digits of the ISSN multiplied by its position in the number, the modulus 11 of the sum must be 0. For this reason a new ISSN is assigned to a serial each time it undergoes a major title change, separate ISSNs are needed for serials in different media.
Thus, the print and electronic versions of a serial need separate ISSNs. Twitter — Twitter is an online news and social networking service where users post and interact with messages, tweets, restricted to characters.
Registered users can post tweets, but those who are unregistered can only read them, users access Twitter through its website interface, SMS or a mobile device app.
The service rapidly gained worldwide popularity, in , more than million users posted million tweets a day, and the service handled an average of 1. In , it was one of the ten most-visited websites and has described as the SMS of the Internet. As of , Twitter had more than million monthly active users. On the day of the U. Jack Dorsey, then a student at New York University. The original project name for the service was twttr, an idea that Williams later ascribed to Noah Glass, inspired by Flickr.
The developers initially considered as a code, but later changed it to for ease of use. The definition was a short burst of inconsequential information, and chirps from birds, and thats exactly what the product was. The first Twitter prototype, developed by Dorsey and contractor Florian Weber, was used as a service for Odeo employees.
Williams fired Glass, who was silent about his part in Twitters startup until , Twitter spun off into its own company in April Williams provided insight into the ambiguity that defined this early period in a interview, With Twitter and they called it a social network, they called it microblogging, but it was hard to define, because it didnt replace anything.
There was this path of discovery with something like that, where over time you figure out what it is, Twitter actually changed from what we thought it was in the beginning, which we described as status updates and a social utility.
It is that, in part, but the insight we eventually came to was Twitter was really more of an information network than it is a social network, the tipping point for Twitters popularity was the South by Southwest Interactive conference. During the event, Twitter usage increased from 20, tweets per day to 60,, the Twitter people cleverly placed two inch plasma screens in the conference hallways, exclusively streaming Twitter messages, remarked Newsweeks Steven Levy.
It was formed in from the amalgamation of the American Institute of Electrical Engineers, today, it is the worlds largest association of technical professionals with more than , members in chapters around the world. Its objectives are the educational and technical advancement of electrical and electronic engineering, telecommunications, computer engineering, IEEE stands for the Institute of Electrical and Electronics Engineers.
The association is chartered under this full legal name, IEEEs membership has long been composed of engineers and scientists. For this reason the organization no longer goes by the name, except on legal business documents.
The IEEE is dedicated to advancing technological innovation and excellence and it has about , members in about countries, slightly less than half of whom reside in the United States. The IEEE serves as a publisher of scientific journals and organizer of conferences, workshops.
IEEE develops and participates in activities such as accreditation of electrical engineering programs in institutes of higher learning. IEEE has a dual complementary regional and technical structure — with organizational units based on geography and it manages a separate organizational unit which recommends policies and implements programs specifically intended to benefit the members, the profession and the public in the United States.
Reed Business Information — Reed Business Information is a provider of data services, business information and workflow solutions to businesses. The company produces data, analytics and information for businesses and it provides services to specific sectors including chemicals, agriculture, HR, property, finance, science and aerospace. Cryptographic hash functions are mathematical operations run on digital data, by comparing the computed hash to a known and expected hash value, a person can determine the datas integrity.
For example, computing the hash of a file and comparing the result to a previously published hash result can show whether the download has been modified or tampered with. A key aspect of cryptographic hash functions is their collision resistance, SHA-2 includes significant changes from its predecessor, SHA They use different shift amounts and additive constants, but their structures are virtually identical.
The United States has released the patent under a royalty-free license, in , an algorithm emerged for finding SHA-1 collisions in about 2, times fewer steps than was previously thought possible. In , an example of a SHA-1 collision was published, the security margin left by SHA-1 is weaker than intended, and its use is therefore no longer recommended for applications that depend on collision resistance, such as digital signatures. The updated standard included the original SHA-1 algorithm, with updated technical notation consistent with that describing the workings of the SHA-2 family.
In October , the standard was updated in FIPS PUB , including SHA from the change notice, the primary motivation for updating the standard was relocating security information about the hash algorithms and recommendations for their use to Special Publications and Detailed test data and example message digests were also removed from the standard, padding the final data block must still occur prior to hash output. Namecoin — Namecoin is a cryptocurrency and the first fork of the bitcoin software.
It is based on the code of bitcoin and uses the same proof-of-work algorithm and it is limited to 21 million coins.
Unlike bitcoin, Namecoin can store data within its own blockchain transaction database, the original proposal for Namecoin called for Namecoin to insert data into bitcoins blockchain directly.
Anticipating scaling difficulties with approach, a shared proof-of-work system was proposed to secure new cryptocurrencies with different use cases. Namecoins flagship use case is the censorship-resistant top level domain. A peer-to-peer network similar to bitcoins handles Namecoins transactions, balances and issuance through SHA, the issuing rate forms a geometric series, and the rate halves every , blocks, roughly every four years, reaching a final total of 21 million NMC.
Namecoins are currently traded primarily for USD and other cryptocurrencies, mostly on online exchanges, to avoid the danger of chargebacks, reversible transactions, such as those with credit cards or Paypal, are not advised since Namecoin transactions are irreversible. Payments and records in the Namecoin network are made to addresses and they are strings of 33 numbers and letters which begin with the letter N or M.
Initially addresses beginning with 1 existed but this was changed to avoid confusion with Bitcoin addresses, each Namecoin record consists of a key and a value which can be up to bytes in size.
Each key is actually a path, with the preceding the name of the record. The current fee for a record is 0. Soon a developer decided to implement this idea to earn this reward, on April 18, Namecoin was introduced by Vinced as a multipurpose and distributed naming system based on bitcoin. Two years later, in June , NameID was launched and it is a service to associate profile information with identities on the Namecoin blockchain and an OpenID provider to allow logging into existing websites with Namecoin identities.
The main site itself is accompanied by a protocol for password-less authentication with Namecoin identities, a corresponding free-software implementation. In October , Michael Gronager, main developer of libcoin, found a security issue in the Namecoin protocol and it was successfully fixed in a short timeframe and was never exploited, except for bitcoin.
Peercoin — Peercoin, also known as PPCoin or PPC, is a peer-to-peer cryptocurrency utilizing both proof-of-stake and proof-of-work systems. Peercoin is based on an August paper which listed the authors as Scott Nadal, Sunny King, who also created Primecoin, is a pseudonym.
Nadals involvement had diminished by November , leaving King as Peercoins sole core developer, Peercoin was inspired by bitcoin, and it shares much of the source code and technical implementation of bitcoin. Unlike bitcoin, Namecoin, and Litecoin, Peercoin does not have a limit on the number of possible coins.
There is an aspect to Peercoin as the transaction fee of 0. This feature, along with increased efficiency, aim to allow for greater long-term scalability. A peer-to-peer network handles Peercoins transactions, balances and issuance through SHA, Peercoins are currently traded for fiat currencies, bitcoins, and other cryptocurrencies, mostly on online exchanges.
Reversible transactions are not normally used to buy Peercoins as Peercoin transactions are irreversible, payments in the Peercoin network are made to addresses, which are based on digital signatures. They are strings of 34 numbers and letters which begin with the letter P. One can create as many addresses as needed without spending any Peercoins and it is quite common to use one address for one purpose only which makes it easy to see who actually sent the Peercoins. New coins can be created in two different ways, mining and minting, mining uses the SHA algorithm to directly secure the network.
Minting rewards users in proportion to the coins that they hold, there are long term plans to reduce gradually the amount of mining and to rely more on minting. This is to create a distribution and could lead to an increase in the reward from minting.
With bitcoin, for example, there is a risk of resulting from a monopoly on mining share. Titcoin — Titcoin is a derivative of the bitcoin source code with key modifications to the software which greatly improve transaction speeds and network difficulty readjustments. Titcoin is notable for being the first altcoin fully recognized as a form of currency by a major industry trade organization.
In , Titcoin received two nominations at the XBIZ Awards ceremony which honors companies that play a part in the growth. The founders developed Titcoin for the entertainment industry as a cash alternative payment system for performing anonymous transactions.
Titcoin allows consumers of adult entertainment to perform transactions without using any personally identifiable information, Titcoin also benefits adult businesses with zero chargebacks and freedom from dealing with traditional financial institutions. On January 17,, Titcoin was formally revealed to the community with initial coin specifications. On June 21,, the Titcoin wallet and source code was released with a soft launch for the cryptocurrency community followed by a hard launch for the public.
Titcoin is a clone that leverages the same SHA set of cryptographic hash functions. Titcoin has received award nominations and ratings from notable organizations within the adult entertainment. Ethereum — Ethereum is an open-source, public, blockchain-based distributed computing platform featuring smart contract functionality.
It provides a decentralized Turing-complete virtual machine, the Ethereum Virtual Machine, Ethereum also provides a value token called ether, which can be transferred between participants and is used to compensate participant nodes for computations performed.
Gas, an internal transaction pricing mechanism, is used to prevent spam on the network, Ethereum was initially proposed in late by Vitalik Buterin, a cryptocurrency researcher and programmer. Development was funded by an online crowdsale during July—August , the system went live on 30 July Ethereum was initially described in a paper by Vitalik Buterin.
More specifically, Buterin had argued to the core developers that the platform needed a more robust scripting language for developing applications. Failing to gain agreement, he proposed development of a new platform with a more general scripting language, Buterin believes that many applications could benefit from Bitcoin-like software. The Ethereum software project was developed in early by a Swiss company.
Subsequently, a Swiss non-profit foundation, the Ethereum Foundation was set up as well, development was funded by an online public crowdsale during July—August , with the participants buying the Ethereum value token with another digital currency, bitcoin.
While there was praise for the technical innovations of Ethereum. Ethereums live blockchain was launched on 30 July , the initial version of Ethereum—called Frontier—uses a proof of work consensus algorithm, although a later version is expected to replace that with a proof of stake algorithm. Since the initial version, the Ethereum network has accomplished several so-called hard forks, first hard fork The first hard fork introduced a difficulty bomb to incentivize an upgrade to proof of stake when this system will be ready.
Second hard fork—Homestead release The second hard fork was made in Spring and marked the first stable release, as a consequence of the way the DAO was programmed, these moved funds would remain unavailable for withdrawal for about a month. After a few weeks discussion, on 20 July Ethereum hard-forked creating a new fork to reverse the hack and return The DAO funds and this was the first time any mainstream blockchain was forked to reverse a transaction in order to make reparations to investors in a failed enterprise.
This hard fork successfully de-bloated the blockchain and attempted to prevent further attacks by hackers. The value token of the Ethereum blockchain is called ether and it is listed under the diminutive ETH and traded on cryptocurrency exchanges. It is also used to pay for fees and computational services on the Ethereum network.
Inspired by and technically nearly identical to bitcoin, Litecoin creation, after Bitcoin, Ethereum, Dash and Ripple, Litecoin is the fifth-largest true cryptocurrency by market capitalization. It was a fork of the Bitcoin-Qt client, differing primarily by having a decreased block generation time, increased number of coins, different hashing algorithm.