What kind of security system is blockchain, and what are the terms?
To define the blockchain in one sentence is the security system, and the currency used on this basis is the cryptocurrency. If there is no blockchain technology, all cryptocurrencies are in fact like the acorns of Cyworld, becoming units that can only exist on specific websites. However, the blockchain-based cryptocurrency can transparently record transaction details in a ledger that anyone can check. The distributed data storage technology is stored in multiple computers after copying. There are multiple computers to verify records to prevent hackers from attacking. Take a bank as an example. It manages the electronic certificate and OTP card and other passwords in one place in the bank, and operates all the remittance processes. Therefore, if there is a problem with the bank server or a problem with the data, it will cause a large accident. For this reason, banks also adopt double or triple security devices for the safety of the remittance process. But these safety devices entail huge costs. The blockchain does not deal with these problems in the same place. It stores copies of various records, distributes them to all computers, and encrypts various data in real time for safekeeping. A block means a collection of most transaction information. First, if the structure of the block is explained in three stages, the block is the unit for storing data, which can be divided into the main body and the head. The main body includes the transaction content, and the header includes the password. Blocks are generated according to the pre-defined cycle, the transaction records are collected to make blocks, the credibility is verified, and the previous blocks are connected to become the form of a blockchain. The block that starts here for the first time is called the genesis block. Cryptocurrency Wallet (Wallet) Each user generates and keeps a private key and a public key, generates an address based on the public key, and uses this address for transactions. The public key is similar to a passbook account that can be shared with an unspecified number of people. The private key is similar to a passbook password that only the user can access. To give an example of loss, a hacker attacked the personal PC of an exchange employee, obtained the user's personal information and falsely claimed that he was an exchange employee, and stolen cryptocurrency after obtaining the private key information from the user. The private key, like the passbook password, is an important security item that must never be disclosed to the outside world. Moreover, at the end of 2013, a host of Bloomberg TV broadcasted the transfer of bitcoins to colleagues. As a result, all his bitcoins were stolen. Because the TV camera captured the host’s Bitcoin wallet very accidentally, the private key was leaked. Transaction Refers to transactions in which blockchain moves actually occur, and transactions can only be carried out between users who are designated with the private key signature of each user. The transaction record is stored in the block and cannot be changed or forged after being confirmed by the authentication process. In order to complete the transaction, it needs to be approved through proof of work, which takes some time. Block Blockchain is a chain of blocks of transaction records connected all over the world. As the name suggests, it is equivalent to a transaction record group. Block and blockchain information can be easily confirmed through blockchain.info. Each transaction has its own unique transaction number, which records the number of messages sent from what address to what address. Each block is connected in sequence according to the transaction history. Each block has information linked to the front and back blocks, so it is easy to judge whether it has been operated. The operated block disappears from the network after the confirmation process. Miner In order to prevent double payment problems with blocks that include transactions, a proof-of-work protocol is used to connect the main body of the block. The blockchain network is maintained by this mining machine, and the mining machine obtains the blockchain as its compensation. However, the method of uploading additional new chains on the existing stable blockchains is now more adopted, so there are many blockchains without new mining (mining). The MP coin introduced in this white paper also advertises this approach. In addition to these, the following terms are often used in blockchain-based cryptocurrencies. Peer-to-peer network A communication network that does not have a central server, so that all nodes can communicate in the same level. Hash Transform a string into a shorter value or Key. The hash can be used to confirm whether the information has been forged. SHA256 (Security Hash Algorithm) A function that converts a specific value or character string into a 256-bit (32-byte) value. At the same time, as long as the input value changes slightly, the result value will be very different, so it is often used in the field of passwords. Node The basic unit of terminal equipment or communication processing device that constitutes a communication network. Distributed computing (Distributed compuTIng) A technology that links multiple computers to improve computing performance and efficiency through mutual cooperation. Private key A character string with access to the public key authority equivalent to the encrypted currency address. Because it serves as a password, it must not be disclosed to the public. Similar to the password of a passbook. Public key Encryption currency address string. Play the role of an account, which can be disclosed to others. Account number similar to a passbook. Approval (Confirm) In order to confirm whether the cryptocurrency is counterfeit, each node of the cryptocurrency network verifies the legitimacy of the blockchain through the proof of work or equity proof process. Double Spending Refers to the situation where the same amount of money is used more than twice in a transaction. It is likely to happen in non-face-to-face online transactions. The problem of double payment is a very important item in proving the credibility of cryptocurrencies. 51% rule It is a method to verify whether the blockchain is forged. Each node of cryptocurrency often uses its own blockchain to compare whether it is the same as the blockchain held by other nodes to verify whether it is forgery. If it is the same as the blockchain held by more than half of the people, it is considered the original and continues to be kept. If they are different, it is considered to have been forged, and after discarding, copy the blockchain held by more than half of the people and keep it. Proof-of-work It is a means of deliberately making all individuals who want to connect to the computer system perform time-consuming tasks to protect the system from malicious linkers who attempt to attack the system. The process of proof-of-work slows down the time for new block information to be transmitted to the network, and prevents the manipulated blockchain from quickly spreading on the network. Bitcoin automatically generates questions that take 10 minutes to answer. The first participant to answer the question has the right to create a new blockchain by linking his own block to the existing blockchain. Through this process, the blockchain is updated every 10 minutes on average, and each node earns the time to verify the block within 10 minutes. At the same time, participants who answer questions every 10 minutes, as compensation, will give themselves a certain amount of new bitcoins. Earlier miners could find the answer within 10 minutes using ordinary PCs, but now as the number of competitors who want to mine increases, the difficulty of the problem is gradually increasing, and faster calculations are required. There are also professional miners who mix graphics cards with fast computing GPUs to open factories. From the conclusion, there are problems such as consuming computing resources and power resources. Proof-of-stake Approvers who hold more currency can generate blocks first. The prerequisite is that participants who hold a large amount of currency in order to protect the value of their currency will not damage the trust of the system. Therefore, the method of proof of stake is not to consume computer resources but to generate blocks through stakes held by oneself. That is, it is determined based on the equity held by oneself and the date when the equity is generated. The equity date used to generate a block is initialized. The basic structure is no different from the proof of work, but the difficulty of hashing according to the amount of money will be reduced, so compared with the proof of work, it has the advantage of relatively less resource consumption. Byzantine General Problem (ByzanTIne General Problem) It refers to the fable that three computer engineers including Leslie Lamport (Leslie Lamport) suggested to Microsoft in 1982. In order to occupy a city, the generals of Byzantium wanted to besiege. They had to send signal soldiers to notify the scattered troops to start the attack together. This is how to solve the problem of treachery or fake signal soldiers and how to determine the timing of simultaneous attacks. This problem contains problems that may occur in a decentralized computing environment, which reminds people of the importance of the "51% rule" of the blockchain and the "Proof of Work" operation. Bitcoin (Bitcoin, BTC) The world's first P2P-based cryptocurrency produced by Satoshi Nakamoto in 2009. Abbreviated as BTC. New bitcoins are issued by paying bitcoins to the first node that produces a block through the proof of work. The maximum circulation is 21 million BTC. As of June 2017, approximately 17 million BTC have been issued. Each approval takes an average of 10 minutes and goes through 12 approval processes to complete, so it takes at least two hours to complete the transaction. In actual transactions, it usually takes longer due to slow server speed and other reasons. Bitcoin mining (BTC Mining) It means that Bitcoin nodes compete with each other in order to implement proof of work. In order to induce the implementation of proof-of-work, paying bitcoin as compensation to the first node that successfully implements the proof-of-work is very similar to mining gold, so this concept was born. Bitcoin Cash (BCH/BCC) A cryptocurrency separated from Bitcoin on August 1, 2017. Abbreviated as BCH or BCC. In May 2017, Bitcoin developers and miners around the world decided to determine the block size in order to digest the increased Bitcoin transaction volume. However, due to some developers who thought it might lead to a decrease in mining revenue, Bitcoin was separated into Bitcoin and Bitcoin Cash. Alternative currency (AlternaTIve coin) The general term for all cryptocurrencies except Bitcoin. Ethereum is the most typical alternative currency, and Bitcoin Cash, which is separated from Bitcoin, is also an alternative currency. Ethereum (ETH) In July 2015, the representative cryptocurrency ranked second in total market value developed by Vitalik Butrin. It is a distributed computing platform that reflects transaction records and smart contract functions. Focusing on the feature of recording supplementary information such as contracts in addition to currency transactions, using computer resources held by countless users around the world to form a decentralized network, using this platform to invent a system for recording various information such as SNS, e-mail, and electronic voting. Ethereum supports major programming languages ​​such as C++, JAVA, PYTHON, and GO. Ethereum has an extended language with "Turing completeness", which makes it easy to write smart contracts. The so-called Turing completeness refers to a Turing machine level that can be programmed to mathematical simulation. This shows that all programs that are designed to be editable on ordinary computers have infinite scalability, as the name suggests. Ethereum also uses the cryptocurrency "Either". Ether plays the role of a medium that makes the effective exchange of various virtual assets possible, and is used as a currency to pay transaction fees. The transaction history is accumulated into blocks on the P2P network, and the smart contract code and execution history are also recorded. Ethereum generates a block every 12 seconds. Litecoin (Litecoin, LTC) In October 2011, a cryptocurrency developed by Charles Lee, who used to work at Google. Based on Bitcoin when it was developed, all technologies are the same as Bitcoin. The biggest difference with Bitcoin is that it is 4 times faster than the average Bitcoin block mined in 10 minutes, and a block is generated every 2.5 minutes. Moreover, the maximum circulation has reached 84 million, which is four times the circulation of Bitcoin. It can be seen as reflecting the developer's philosophy of pursuing a lightweight version of Bitcoin. Ripple (XRP) Ripple is the third largest cryptocurrency in total market value after Bitcoin and Ethereum. Unlike other currencies, it is based on the remittance system, so its structure is also different. The settlement speed is faster than other currencies, and the expansion performance is very good. EOS As a price for accepting donations of EOS software development funds for free, tokens issued based on Ethereum. As of May 2018, the total market value ranked fifth. EOS software was developed by Block.one in 2016, using the Delegated Proof-of-Stake method, which has a faster transaction speed than Ethereum. It also has the feature that users do not need to pay commissions but are paid by developers. As of April 2018, Ethereum can process 20 transactions per second, but EOS can process 3,000 transactions on average. The ICO was conducted on the Ethereum blockchain in the form of flat sales. The original plan was to transfer the server to its own mainnet on June 2, 2018, but it was discovered by Qihoo 360, a Chinese Internet security company, on May 30, 2018. In addition, there are fatal flaws in its safety. Token Cryptocurrencies and tokens usually mean the same thing. Under normal circumstances, having an independent blockchain network is called cryptocurrency. Bitcoin and Ethereum are the most typical examples. In contrast, if there is no independent blockchain network, it is called a token. For example, EOS is the most typical token. The ERC20 (Ethereum Request for Comment) token, which can be called the current global token standard, refers to the token that can be used on the DAPP (Decentralized ApplicaTIon) based on the Ethereum network blockchain. Broadly speaking, in addition to currency, it also has the function of assets. If the Ethereum network blockchain is compared to the Google e-market store, then DAPP is equivalent to an application that can be downloaded in the Google Google store. The cryptocurrency called Quantum Chain (QTUM) originally started from ERC20 and was listed in the form of tokens. Through token financing, an independent network was built on this basis (this is called the mainnet line). After that, it is converted from Quantum Chain tokens to Quantum Chain currency through currency swaps. To put it simply, it is not a reflection of Google's electronic market, but an expression of the Apple App Store. In terms of the functionality of cryptocurrency, there is no need to convert from tokens to cryptocurrencies. DEX (Decentralized Exchange) Refers to decentralized exchanges. It can be understood as an over-the-counter exchange between individuals other than large exchanges. It was born to overcome the overbearing and deficiencies of traditional exchanges. All deposits and withdrawals in DEX currency only need to be carried out in the blockchain, not in the tokenized internal wallet provided by the exchange, but to support direct transactions in personal wallets that can be directly connected from the blockchain. It is impossible for anyone to deliberately block deposits and withdrawals in the middle, and can directly rely on the security of the blockchain. There is no danger of server theft or personal information leakage caused by entrusting an existing exchange. Users only need to keep their wallets. Just as Bitcoin will lead the financial economy, which can only be carried out underground in the existing financial circle, to a square where ordinary people can directly participate, DEX will lead the closed trading environment of the existing exchange to a broader grassland. Shenzhen Xcool Vapor Technology Co.,Ltd , https://www.szxcoolvape.com
This is a data anti-counterfeiting technology based on distributed computing technology that no one can modify without authorization and anyone can check the result of the change. The block records all transaction details that have been transmitted to users before the relevant block is found, and is also transmitted to all users through P2P, so transaction details cannot be modified or omitted without authorization. A block has the date of discovery and a link to the previous block. This collection of blocks is called a blockchain. To put it simply, it is the technology that binds countless records together. There is no central bank for coinage in cryptocurrency. Currency is generated by searching for blocks every certain period to get compensation. A block is composed of a hash function (a function that converts arbitrary data of any length into fixed-length data) used by related cryptocurrencies. The user searches for the hash by substituting the computing power of the computer into the corresponding function. This process is called mining.
Unlike in the past when transaction records are kept on a central server when electronic money is used for transactions, the blockchain displays transaction records to all users and prevents forgery by comparing them with each other. 
That is, the genesis block refers to the initial block that has not generated any blocks before. Nodes do not keep and manage transaction records in a centralized server, but the servers of everyone involved in the transaction gather to maintain and manage the network. This everyone's server, that is, the participant is called a node. Because there is no central administrator, the role of the node that distributes the block is very important. At least half of the participating nodes agree to generate the block. Each node stores the block in the computer. Even if some of the nodes are stolen and the existing content collapses, the data is still left in most nodes, and the data can continue to be saved. This kind of block structure, even if one of the blocks is stolen, as long as the other linked blocks do not recognize this kind of hacking, the hacking attempt will be rejected. From this point of view, it is very innovative in terms of security. There have been no instances of theft at this level of security.
There is another, the most important part of the blockchain is transactions. The part that runs the actual content of the block is the transaction. To put it simply, it is the so-called transaction. The blockchain transfers from one address to another through transactions. Bitcoin and other first-generation blockchain-based cryptocurrencies are basically composed of the following four factors.