Bitcoin Handbook

1. blockchain world is proced by Jingtong technology< Make complaints about br / > block chain

2.

< Introction to cognition & gt

publication time: 2016

recommendation: this book is mainly for programmers. Combined with API programming, we can tell you the principle and usage of cryptocurrency, as well as how to develop related software. For non programmer readers, the first few chapters of this book are still applicable as in-depth introction of bitcoin Book pdf download: https://quant.la/Download

3. In order to understand the technical principle of bitcoin, we need to understand two important cryptographic techniques: hash code: it converts a long string into a fixed length string, and its conversion is irreversible, that is, it is impossible to guess the original string from hash code. Sha256 is mainly used in bitcoin protocol
public key system: corresponds to a public key and a private key, keeps the private key in the application and publishes the public key. When Party A transmits information to Party B, it can use Party A's private key to encrypt the information, and Party B can use Party A's public key to decrypt the information, so as to ensure that the third party cannot impersonate Party A to send the information; At the same time, when Party A transmits information to Party B, it is encrypted with Party B's public key and sent to Party B, and then Party B decrypts it with his own private key, so as to ensure that the third party cannot eavesdrop on the communication between the two people. RSA is the most common public key system, but the lliptic curve digital signature algorithm is used in bitcoin protocol. What's the difference between cash and bank account? Bitcoin is an electronic currency in BTC. In this article, it is also used to refer to the whole bitcoin system. Like opening an account in a bank, the corresponding concept in bitcoin is address. Everyone can have one or more bitcoin addresses, which are used to pay and collect money. Each address is a string that starts with 1. For example, I have two bitcoin accounts, and. A bitcoin account is uniquely determined by a pair of public key and private key. To save the account, you only need to save the private key file. Unlike bank accounts, banks keep all transaction records and maintain the book balance of each account, while bitcoin's transaction records are jointly maintained by the whole P2P network through a pre agreed protocol. How much money is in my account address? Although the current account balance can be seen by bitcoin software, unlike banks, there is no place to maintain the book balance of each address. It can only calculate the account balance in real time through all historical transactions. How do I pay? When I pay from address a to address B of the other party, the payment amount is e. at this time, both parties will announce the transaction information to each network node, telling address a to pay to address B, and the payment amount is e. In order to prevent the third party from forging the transaction information, the transaction information will be encrypted with the private key of address A. at this time, the network node receiving the transaction information can use the public key of address a to verify that the transaction information is indeed sent by address a. Of course, trading software will help us do these things, we just need to input the relevant parameters in the software. What will the network node do after receiving the transaction information? This is the most important part of the bitcoin system, which needs to be elaborated. For the sake of simplicity, only bitcoin protocol has been implemented. In the current version, each network node will save all transaction information synchronously. There are two kinds of transaction information in history, one is & quot; Verified & quot; The transaction information, that is, the verified transaction information, is stored in a series of "blocks". Each & quot; block" Is the previous & quot; bock" The ID of each block is the hash code of the hash code of the block and the new transaction information (see an actual block). The other category refers to those who also & quot; Unverified & quot; The transaction information just paid above belongs to this category. When a network node receives new unverified transaction information (possibly more than one), it can calculate the book balance of each address at that time because the node keeps all the transaction information in history, so it can calculate whether the transaction information is valid, that is, whether there is enough balance in the payment account. After eliminating the invalid transaction information, it first takes out the last & quot; block" Then, the unverified transaction information is combined with the ID, and a verification code is added to form a new "block". It needs a lot of calculation to build a new block, because it needs to calculate the verification code, so that the above combination becomes a block, that is, the first several bits of the hash code of the block are 1. At present, the first 13 bits need to be 1 (generally, the specific method is uncertain), which means that if the block is generated by enumeration method, the average number of enumerations is 16 ^ 13. Using CPU resources to generate a block is called "gold mining", because the proction of the block will get a certain reward, and the reward information has been included in the block. When a network node generates a new block, it will broadcast to other network nodes. However, this network block may not be accepted by the network, because it is possible that other network nodes have proced the block earlier. Only the earliest block or the block with the largest number of subsequent blocks is valid, and the remaining blocks are no longer used as the initial blocks of the next block. How does the other party confirm that the payment is successful? When the payment information is distributed to the network node, the network node begins to calculate whether the transaction is valid (that is, whether the account balance is enough to pay), and attempts to generate blocks containing the transaction information. When six blocks (one direct block and five subsequent blocks) contain the transaction information, the transaction information is considered "verified", so that the transaction is formally confirmed, and the other party can confirm the successful payment. A possible problem is that I will pay the balance of address a to address B, and at the same time pay to address C. If I only verify that the single comparison transaction is valid. At this point, my way of cheating is to generate six blocks including B to B and six blocks including C to C before the truth is revealed. Because I need a very long CPU time to generate a block, compared with the whole network, the probability of my cheating success is very small. What is the motivation of network nodes to proce blocks? As can be seen from the above description, in order to make the transaction information effective, the network node needs to generate 1 and 5 subsequent blocks to contain the transaction information, and such block generation is very CPU intensive. How to let other network nodes help to proce blocks as soon as possible? The answer is very simple. The agreement stipulates that BTC will be rewarded for the address where the block is proced, as well as the Commission promised by both parties. At present, the reward for procing a block is 50btc, which will be halved every four years in the future. For example, the reward will be 25btc from 2013 to 2016. Is the transaction anonymous? Yes, and No. All bitcoin transactions are visible. We can check all transaction records of each account, such as mine. But what's different from the banking monetary system is that everyone's account itself is anonymous, and everyone can open many accounts. In general, anonymity is not as good as it claims. But bitcoin has another advantage in doing black market trading: it can't be frozen. Even if the police trace a bitcoin address, there is nothing they can do unless they trace the computer used by the exchange based on the Internet address. How to ensure that bitcoin does not depreciate? Generally speaking, in the case of equivalent trading activities, the value of money is inversely proportional to the amount of money issued. Unlike the traditional money market, the central bank can determine the amount of money issued. Bitcoin does not have a central issuing institution. Only by procing blocks can we get a certain amount of BTC currency. Therefore, bitcoin's new amount of money depends on: 1. The speed of procing blocks: bitcoin's agreement stipulates that the difficulty of procing blocks is fixed at an average of 2016 every two weeks, about 10 minutes. Moore's law of doubling CPU speed every 18 months will not speed up the proction of block. 2. The number of rewards for block proction: at present, 50 BTC is awarded for each block proced, which is halved every four years. In 2013, 25 BTC is awarded, and in 2017, 12.5 BTC is awarded. Considering the above two factors, bitcoin's currency issuing speed is not controlled by any single node in the network. Its protocol makes the currency stock known in advance, and the maximum stock is only 21 million BTC

4.

Dahua blockchain is a book published by Tsinghua University Press in September 2019, written by Zhang Yingping. This book is a blockchain book that comprehensively explains bitcoin, Ethereum, super ledger and EOS, a blockchain development guide from engineer basic skills, development language to smart contract development, and a blockchain engineer guide from technology, project to career development planning

"Dahua blockchain"

"Dahua blockchain" is a blockchain book that pays equal attention to theory and practice, easy to understand and professional. The blockchain technology guide (the first three chapters) mainly explains the concept of blockchain, blockchain applications, bitcoin, Ethereum, super ledger, EOS and other mainstream blockchain technologies. Through learning, each reader can fully understand the implementation principles of mainstream blockchain technologies and understand the future development trend of blockchain. The practical part of development (the last two chapters) starts from the basic skills of blockchain, simulates the development of real blockchain projects, and explains in detail the design, development and deployment of smart contract and DAPP. Through learning, every reader can master the development of blockchain

5. 1. Bitcoin white paper: a peer-to-peer e-cash system, written by Tsung Nakamoto. Read this white paper first, and then consider other contents
2 FORTRAN 95 programming, written by Peng Guolun
3 Introction to FORTRAN 77 and 90 / 95 programming, written by Ding Zejun
4. Out of control: the new biology of machines, society and economy
5. Necessity, written by Kevin Kelly, mentions 12 inevitable trends in the next 20 years
6. Master bitcoin, this book will provide you with the necessary knowledge to guide you into the bitcoin world
7. Blockchain revolution, written by don Tapscott and Alex Tapscott, tells how the underlying technology of bitcoin has changed money, business and the world
8. Blueprint and guide of blockchain new economy, written by Melanie Swann
9. Blockchain: the concept of quantum wealth, written by Han Feng / Zhang Xiaomei
10. Logic of finance, The author is Chen Zhiwu. The work starts from the cultural and institutional genes of wealth in simple terms, so as to tell readers what the logic of finance is
related books include principles of economics, blockchain: technology driven finance, blockchain Revolution: how bitcoin's underlying technology can change money Business and the world, blockchain technology guide, illustrated blockchain, how blockchain will redefine the world, digital currency: bitcoin data reporting and operation guide, blockchain: from digital currency to credit society, intelligent age, etc. to be honest, blockchain is still a hot resource. It's mainly about judgment (whether it's valuable) and action (to get in early)
recommends a block chain related APP, called golden finance, recommends a public official account, called "Xiao Ke online". The article is rich in materials;

6. Did you ask freebtc
or did you say freebitcoin
this is related to bitcoin. It is estimated that this file is a bitcoin related program, mainly about the content of the notice file. I guess you don't like it. They all have special technical column posts to share
if you are in operation and maintenance, you can take a look at Linux and try it. It's suggested that we take a look at a column in "Linux should learn like this". It's a column that Linux command Encyclopedia (manual) joins our group

7. This article will not deal with the details of algorithms and protocols. I plan to write another article on the principle of bitcoin from the perspective of programmers, where I will explain some key data structures, algorithms and protocols in the bitcoin system from the perspective of technicians
in this article, I will give a virtual village called "bitcoin village". The whole article will tell you the motivation of bitcoin, what problems it has solved, and the goals and design schemes of some key components step by step in the way of storytelling
question
let's start with the motivation of bitcoin< In this world, there is a small village called bitcun, which has hundreds of families. The village is almost isolated from the world and lives on its own. Because there is no large-scale trade, the villagers of Biti village have been living a barter life. That is to say, there is no unified currency among the villagers. The trade between the villagers is basically that Lao Zhang's family exchanges a bag of flour for Lao Li's family's sheep, and Wang's sister-in-law exchanges a basket of wild fruits for Aunt Liu's two feet of cloth. The villagers have been living a simple life<

physical currency
finally one day, the villagers felt it was too inconvenient to barter all the time, so the whole village held a meeting to discuss how to solve this problem. It is suggested that, as a general equivalent, the corresponding relationship between other items and gold should be compiled into a table, such as one gram of gold corresponds to a sheep, one gram of gold corresponds to a bag of flour and so on. At this time, Lao Zhang no longer has to carry a bag of flour and pant to Lao Li's house to exchange sheep. He just needs to get a gram of gold from his home, You can go to Lao Li's house and bring back a sheep. Lao Li can exchange this gram of gold for a bag of flour from anyone who is willing to sell flour. Of course, he can also exchange it for anything equivalent to a gram of gold
at this time, bitcun entered the era of physical currency
symbolic currency
the good times are not long. After a period of time, the disadvantages of physical currency also appear. Because there are not many gold mines near bit village, it takes too much time and effort to mine and smelt gold. With the use of gold, it will be worn, lost or deliberately hoarded. Once again, the whole village sat together and began to discuss countermeasures. At this time, someone said that in fact, we don't have to really use gold. Just find a piece of paper and write "one gram of gold". As long as the whole village agrees that this piece of paper is equal to one gram of gold, the problem will be solved. Others agree, but at the same time, there are new problems: the real gold needs to be mined and smelted, and the gold mine is limited, so mining and smelting also need costs, so no one can make a lot of gold out of thin air in a short time, but writing is different. As long as I have enough paper and pen, I can write as much as I like, then it becomes who has more paper, Maybe ten thousand pieces of paper can be exchanged for a sheep (in fact, there will be inflation in Economics)
I think so. However, at this time, someone proposed a solution: This paper is not effective for everyone. We only know the words written by the respected old village head in the village, and everyone knows the words of the old village head. The old village head wrote some paper and gave everyone the same amount of paper according to the gold stock of each family. For example, when Lao Zhang's family had two hundred grams of gold, the old village head gave Lao Zhang 200 pieces of paper with "one gram of gold" written on it, and took Lao Zhang's gold as collateral. In this way, the old village head collected all the gold in the village into his own home, and gave the equivalent amount of paper with words according to the amount of gold handed in by each family. At this time, the villagers can trade with the paper as gold, and everyone can recognize the words of the old village head, and others can't forge them. In addition, if someone's paper is worn too seriously, he can get it to the old village head to exchange for the new equivalent paper. In addition, the old village head promises that if anyone wants to exchange for gold, he will return the equivalent gold to that person as long as he takes the paper back. Because the amount of gold in the paper written by the old village head is the same as that in the real home, so as long as the principle of destroying as many paper as new paper is strictly followed, every effective paper can always be exchanged for the corresponding real gold
at this time, bitcun entered the era of symbolic currency (paper money). The old village head took on the role of the government and the bank<

virtual currency of the central system
a few years later, the old village head has to check a large number of old banknotes every day, write new banknotes, and record various accounts carefully. One comes and two goes. The old village head is overworked and unfortunately drives to the West
bitcun held another plenary meeting to discuss what to do. At this time, er Gouzi, the son of the old village head, volunteered to take over his father's pen and assume the responsibility of currency issuance. The young village head Er Gouzi was very clever. He did it for a few days and found that he didn't really need to write so much paper. It can be done like this: Villagers hand in all the banknotes and destroy them, but Er Gouzi will record the amount of banknotes handed in by each household. If you want to pay later, for example, if Lao Zhang wants to exchange a gram of gold for Lao Li for a sheep, you should call Er Gouzi together to explain that you want to put a gram of gold in Lao Zhang's name under Lao Li's name. Er Gouzi takes out the account book to see if Lao Zhang has a gram of gold in his name. If so, you can subtract one gram from Lao Zhang's name and add one gram to Lao Li's name. In this way, the payment is completed, At this time, Lao Li heard Er Gouzi confirm that the transfer was completed on the phone, so he could rest assured that Lao Zhang would lead the sheep away
at this time, bitcun entered the era of central system virtual currency. Every villager doesn't need to pay in kind. The payment process becomes the change of the number in the account book maintained by Er Gouzi<

distributed virtual currency
the new two dogs are smart, but sometimes they are smart but they are mistaken for smart. One day, er Gouzi was staring at the account book, thinking that how much money each household in the village has is what I say, then I'm not. So his mind a hot, privately from the old Zhang's account to draw ten grams of gold to his name
I thought it would be perfect, but I didn't expect that Lao Zhang also had the habit of keeping accounts. One day, when he was about to pay, er Gouzi told him that his account was out of money. Lao Zhang checked his account book. It was clear that there were still ten grams left, so he took the account book to find Er Gouzi. This check found the transfer without Lao Zhang's consent
east window incident! Bit village is boiling. The impeachment of Er Gouzi is inevitable, but through this incident, we found that the account book is concentrated in one person's hands:
this system completely depends on the personal credit of the account book holder. If this person does not obey the rules and tampers with the account book at will, then the whole monetary system will collapse
if this family is on fire or the account book is stolen, It will also bring a devastating blow to the whole system.
just when people are at a loss, an otaku scientist named Nakamoto came to the stage and told everyone that he has designed a virtual currency system called bitcoin, which does not rely on any central processor, to solve the above problems. Then he spoke slowly about his plan
let's take a look at how Tsung Nakamoto designed this system<
infrastructure construction
account book disclosure mechanism
Nakamoto first explained that the existing account book should be transformed as follows:
the account book will no longer record the balance of each villager, but only record each transaction. That is to record the payer, payee and payment amount of each transaction. As long as the initial state of the account book is determined, each transaction record is reliable and chronological, how much money each person currently holds can be calculated
the account book is changed from private to public, so that any villager can obtain the current complete account book as long as they need it. The account book records all the transaction records from the creation of the account book to the current
as soon as this remark is made, it will be fried immediately. The first one doesn't matter, but the second one is simply unacceptable, because the account book records all the villagers' transactions, so that everyone's privacy is not completely exposed
Nakamoto is in no hurry and takes out a pair of strange things
identity and signature mechanism (public key encryption system)
Mr. Nakamoto said, don't panic. Under his system, no one trades with his real identity, but with a unique code name
he showed the magic things in his hand and said that these two things were called secret seal and seal scanner respectively. Later, he will give each household in the village a secret seal and a seal scanner. The functions of the two are as follows:
the secret seal can be stamped with a seal on the paper. The seal of each seal implies a unique string of characters in the whole village, but it can't be seen by the naked eye. We can't make the corresponding seal through observation
the seal scanner can scan a sealed seal, read out the hidden information, and display a string of characters on the LCD screen
with these two magical things, you can trade without revealing your real identity, and the string of characters implied in the seal is the code of the family. How to use secret seal and seal scanner to trade will be described in detail below<
establish a virtual miner Organization (Mining Group)
next, Nakamoto Tsung recruits virtual miners for the whole village. The recruitment requirements are as follows:
miners are divided into groups, one group can be a single family, or several families can be combined into a group
becoming a miner does not affect the normal use of currency
miners spend a certain amount of time every day engaged in bitcoin "mining" activities, However, unlike gold mining, virtual miners can complete their work at home without taking tools to do field work.
miners have a certain possibility of getting paid. The more efforts they make in mining activities, the more likely they are to get paid.
miners can quit at any time, or new miners can join in at any time.
soon, About a fifth of the villagers join bitcoin miners and are divided into seven groups
set up the initial account book (Genesis block)
next, Nakamoto announced that according to the account book in ergouzi's hand, all the gold mortgaged will be returned to each villager according to the balance recorded in the account book, and then the account book will be completely destroyed
then, Nakamoto takes out a new account book and records some transaction records on the first page of the account book. In particular, the payer column of these records is "system", while the payee is the hidden character corresponding to each seal, representing the initial time. The system allocates a certain number of bitcoins to each household by default, but the number is very small, only a few, Even some unfortunate villagers didn't get bitcoin
then Mr. Nakamoto said that since there are very few bitcoins on the market, you can go back to the era of using gold as currency. Since I'm not the village head, I don't have the right to force you to recognize bitcoin. You can decide whether to accept bitcoin or not. However, with the flow of bitcoin and the activities of miners, bitcoin will graally increase
payment and transaction

8. Published works
breakthrough of TOEFL core vocabulary in 21 days
high score composition of TOEFL
time as a friend: use your mind to liberate (new version)
full course guidance of SAT official guide
breakthrough of new TOEFL iBT vocabulary classification
TOEFL 6 score composition

Li Xiaolai, former teacher of New Oriental TOEFL Reading and composition, At present, we are the partner of EDR international ecation consulting

9.

Let me use the facts to answer this question

liars disgusting companies, if more money, idle boring will skip

half a year, constantly harass you to call, lure you with a successful membership marriage certificate, although knowing it is routine, but also inevitably have a try mentality, such as me

three months of membership, 20000 membership fee, at most a month to see two people, see the cost is 3500.

1. every day with big data recommend three people, if there is mutual selection, the so-called matchmaker will contact to meet. Listen, it's very high-tech. the actual rate of mutual selection is less than 1%. It's not that you don't look up to each other, it's just invalid recommendation. You recommend Wuhan from Shanghai, and others explicitly write that they hope that those under 25 will also recommend you, and they don't want to recommend you from other places. Hongniang pushes the pot to say that big data is inaccurate. Do I spend tens of thousands of yuan to buy inaccurate ones, What's more, it should be the same

2. that there is a matchmaker's recommendation, so if you take the money, you should do things. Matchmakers in the old society all know that it's good to recommend one to you manually every month, and in order to complete the task, they still find a person who they don't think is reliable. After seeing it, he said to me, "Oh, I don't think it's reliable. Why did I pay for it? What about the early screening and efficiency saving

3. the people recommended are not VIP members at all, they are experience members, and it is not clear that they want me to pay for your free sales, cheat people to join the club

< / OL >

42000 membership fee for three months, 7000 per month, meeting two people at most and 3500 per person per month. Just seeing one side is equivalent to paying 3500 yuan, and buying a bag doesn't smell good. Or in order to account for the past to find their own said unreliable people

5. I pretend to call you every week to show that I'm serving you. It makes you feel that you've spent money to be served. As a result, all the content you said is slobbery, routine, and what training manual you recited. It doesn't have any practical significance. At first, I would talk to them. Later, I feel sick and waste time.

6, It's hard to meet the right people under great pressure. They make up beautiful prospects for you and tell you how excellent you are. I'm sure I can help you. More or less, you will have the mentality of trying. But I advise you that your money is earned through hard work. Buy yourself a delicious meal and add clothes to your parents, Don't take advantage of these people who use social dividends to make dirty money. The real solution is to expand your social circle. Don't be lazy and take part in various activities. Otherwise, time and money will be wasted in the end

I hope everyone who hasn't found the right person should be optimistic and find the right person