Original transaction information of blockchain

1.

If you want to understand the application of blockchain, you can refer to many books and opinions, such as illustrated blockchain, blockchain: reshaping the economy and the world, blueprint and guide of new economy, and articles of coin'an community, including a detailed understanding of the platform of coin'an community, with great strength

As the name suggests, blockchain is composed of block and chain. It is a new application mode of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and so on. It is a kind of chain data structure that combines data blocks in order according to the time sequence, and it is a secure and reliable distributed account book that can not be tampered with and forged by means of cryptography

in 2008, in his paper bitcoin: a peer-to-peer e-cash system published by Nakamoto, he first proposed the idea of blockchain and encrypted digital currency. Starting from bitcoin, blockchain has become the underlying technology of various digital currencies

Second, the working principle of blockchain:

1. The basic concepts include: (1) transaction: one operation will change the account status once, such as adding a record 2) Block: records the transaction and status data within a specified time, which is a consensus and preservation of the current account status 3) Chain: it is composed of a series of blocks in chronological order, which is the log record of the whole state change. If you understand the working concept of blockchain, it is not difficult to understand its working principle. Suppose there is a distributed data logbook, which can only be added, not deleted or changed. Its structure is a linear chain formed by a series of "blocks" (which is also the source of the name of "blockchain"), and new data must be put into a new block to be added, The maintenance node can propose a new block, but it must go through a certain consensus mechanism to reach an agreement on the final selected block

2. Take bitcoin as an example to see the working principle of blockchain

the block of bitcoin is divided into block head and block body

Core advantages and characteristics of blockchain

1. The verification, accounting, storage, maintenance and transmission of decentralized blockchain data are all based on distributed system structure. There is no centralized hardware or management organization, and the rights and obligations of any node are equal, The data blocks in the system are jointly maintained by the nodes with maintenance function in the whole system. 2. The open and transparent system is open. In addition to the private information of all parties to the transaction is encrypted, the data of the blockchain is open to all. Anyone can query the blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent. 3. Security blockchain uses consensus based specifications and Protocols (such as a set of open and transparent algorithms) to enable all nodes in the whole system to exchange data freely and safely in a de trusted environment, so that the trust in "people" is changed into the trust in machines, and any human intervention does not work. 4. Information cannot be tampered with. Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% (almost impossible) nodes in the system can be controlled at the same time, the modification of the database on a single node is invalid. Therefore, the data stability and reliability of the blockchain are extremely high. 5. Anonymity because the exchange between nodes follows a fixed algorithm, and its data interaction does not need trust (the program rules in the blockchain will judge whether the activity is effective or not). Therefore, the counterparties do not need to let the counterparties generate their own trust by disclosing their identities, which is very helpful for credit accumulation

At present, the most popular classification of blockchain is to divide blockchain into public blockchain, private blockchain and consortium blockchain according to different participants

1. Public chain: anyone can participate in the use and maintenance, and can obtain the effective confirmation of the blockchain. Public chain is the earliest blockchain and the most widely used blockchain at present, such as bitcoin blockchain. The information is completely public

if the licensing mechanism is introced, it includes private chain and alliance chain. 2. Private chain: a company or indivial only uses the blockchain technology, enjoys the exclusive write permission of the blockchain, and does not disclose the information. At present, conservative giants (traditional finance) want to experiment with private blockchain, and the application procts of private blockchain are still groping. 3. Alliance chain: it is a blockchain between the public chain and the existing chain, which is jointly controlled by multiple organizations. The use of the chain is managed with authority, which can be controlled by the manager, and also open to others according to the manager's wishes. In addition, according to the different use scenarios and purposes of blockchain, it can be divided into currency chain for the purpose of digital currency, property chain for the purpose of recording property rights, and crowdfunding chain for the purpose of crowdfunding

On May 28, Ma Huateng, CEO of Tencent, proposed the anti-counterfeiting method based on cloud integrated blockchain technology, which is far more efficient than traditional anti-counterfeiting methods. The future anti-counterfeiting verification scenario may only require users to use their mobile phones for simple scanning, and a large number of complete information based on different dimensions can be obtained

take Maotai liquor as an example:

distillery address, proction workshop, operation staff, inspector, delivery time, transportation vehicle information and driver information,

liquor year, raw material source, raw material supplier, storage warehouse number, raw material transportation vehicle and driver information,

all information can be accurately traced, permanently recorded and tampered with

the above information can be easily verified

2. Food safety issues as early as last November, Wal Mart has cooperated with IBM to track the source of food by using blockchain technology, so as to ensure the safety of food and increase the circulation of food to rece costs. For Wal Mart and other large supermarkets, it took a few days to investigate the source of problem food, After using this technology, only one item of proct information is needed to achieve accurate traceability, and important information such as food origin, inspector, supplier, logistics and transportation can quickly find problems in a few minutes. Currently, procts tracked by blockchain include packaging procts from the United States and pork from China

3. Information security

blockchain technology is promoting an information security technology revolution. (1) identity protection PKI is a common public key encryption technology in e-mail, message application, website and other communication applications. However, since the implementation of most PKI, the centralized trusted third party certification authority (CA) is used to issue, activate and store user certificates. Hackers can attack PKI to fake user identity or crack encrypted information

certcoin is the first PKI implementation of blockchain, which comes from MIT, removes the centralized authentication center, and uses blockchain as a distributed ledger for domain name and public key

pomcor company: blockchain PKI implementation path: keep the authentication center, and use blockchain to store the hash value of issued and activated certificates. Users can verify the authenticity of certificates through decentralized and transparent sources, and can also improve the network access performance through local authentication of secret key and signature based on blockchain

(2) data integrity protection

guardtime developed a secret key free signature architecture (Ksi) based on blockchain technology to replace the secret key based data authentication technology. Ksi stores the hash table of the original data and files on the blockchain, runs the hash algorithm to verify other copies, and compares the results with the data stored in the blockchain. Any data tampering will be found quickly because the original hash table is stored in millions of nodes

(3) key infrastructure protection

the "Achilles heel" of the Internet, DDoS has entered the TB era, DDoS is still the simplest weapon for hackers to bring down the big target with low cost, DNS service is the primary target for hackers to carry out large-scale destruction, but blockchain technology is expected to fundamentally solve the problem

The distributed storage of

blockchain makes hacker attacks lose focus. Nebulis is developing a distributed DNS system, which uses Ethereum blockchain and interstellar Internet file system (IPFs, the distributed substitute of HTTP) to register and resolve domain names. The biggest weakness of DNS is caching, which makes DDoS attacks possible. It is also the bane of the centralized government's censorship of social networks and manipulation of DNS registration. A highly transparent and distributed DNS system can effectively prevent any entity, including the government, from arbitrarily manipulating records

(1) digital currency: improve the convenience of currency issuance and use, such as bitcoin and Ethernet in foreign countries, and guorenbao in China

from the use of physical transactions, to physical currency and credit currency, and then to the rise of bitcoin network, more and more people are aware of the distributed ledger blockchain technology behind it, and graally apply it in many scenarios other than digital currency

(2) cross border payment and settlement: realize point-to-point transaction, rece intermediate fees

transfer and payment. At present, the most mature application of blockchain technology is payment and transfer. Blockchain technology can avoid complicated systems, save the process of inter-bank reconciliation and review, and accelerate the settlement speed; Virtual currency can rece transaction costs without the intervention of clearing house. Different countries have different clearing proceres. It takes two or three days for a single remittance to arrive, which is inefficient and accounts for a large proportion of funds in transit. No longer through the third party, through the blockchain technology to form point-to-point payment. By eliminating the link of the third-party institutions, we can make full day payment, real-time payment, withdraw cash quickly and rece the hidden cost, which helps to avoid the capital risk. It is timely and convenient

(3) bills and supply chain financial business: rece human intervention, rece costs and operational risks

value transfer between point-to-point, control and verify physical bills or central system; Intermediaries will be eliminated and human intervention reced. With the improvement of efficiency, financing channels are more unblocked, risks are lower, and multiple parties benefit

(4) securities issuance and Trading: realize quasi real-time asset transfer, accelerate the speed of transaction clearing

the application of blockchain technology can make the process of securities trading more concise, transparent and fast, rece the plication of IT system, and improve the efficiency of market operation. For stocks, blockchain can eliminate paper and pen or electronic form records, rece human errors in trading, and improve the transparency and traceability of trading platform. Citigroup and Nasdaq cooperate to promote blockchain applications

(5) customer credit investigation and anti fraud: rece the cost of legal compliance, prevent financial crimes

the customer information and transaction records recorded in the blockchain help banks identify abnormal transactions and effectively prevent fraud. The technical characteristics of blockchain can change the existing credit reference system, and store the data of customers with bad records in the blockchain when the bank concts "know your customer" (KYC)

equity crowdfunding:

2.

first, define the

blockchain as an open network ledger. It originated from bitcoin and is the underlying technology of bitcoin. In bitcoin transactions, all the information of transaction records will be packaged into a "block" for storage. With the expansion of information exchange, one block links with another, forming a blockchain

Second, the digital currency represented by bitcoin is a point-to-point e-cash system. Among them, every transaction will broadcast to all participants in the network, and it will be recorded in the account book after repeated confirmation, which is called "blockchain". Each participant will have his own account book. In this way, when false information occurs, it can be broken through mutual verification, so as to ensure network security

in the blockchain, every node is equal, and there is no centralized management organization. This "decentralized" feature makes the blockchain do not need to rely on a third party, its operation does not need any human intervention, and it can independently conct self verification. In addition, the network of blockchain is open to the world, and anyone can query data through the public port, so the whole system is highly transparent

In a word, blockchain is a reliable database and a reliable "account book". In the future, it will be applied in cross-border payment, securities, loans, voting, etc. For example, in cross-border payment, with the security of blockchain, you can remit money to the world anytime and anywhere, which saves a lot of intermediate links and high fees

3. The analysis of Chongqing jinwowo network is as follows:
each node on the blockchain can verify the integrity and authenticity of the account book to ensure that all transaction information is not tampered with, true and effective
every node on the blockchain keeps copies of all transaction information. When the number of data and participants on the blockchain is very large, the cost of modifying information will be very high. At least 51% of the computing power of the whole network is needed to modify information, and the modification cost may far exceed the expected revenue
when the information of some nodes is maliciously tampered with, other nodes on the blockchain will find the information that has not formed a "consensus" in a short time and maintain and update it.

4.

1. Jinrong China Financial Instry Co., Ltd.

this is a digital currency trading platform in Hong Kong. At the beginning of trading, it developed on the principle of safeguarding the rights and interests of customers. Similarly, in order to expand trading customers, the company launched the privilege of opening accounts free of charge, and gave customers some concessions in some festivals, This is an important reason why the enterprise takes the first place in the domestic formal blockchain platform

2. Bitfinex

is a digital currency trading platform in Hong Kong, China. It is one of the largest cryptocurrency exchanges in the world. It occupies an important position in the world's cryptocurrency trading and circulation. It also provides the world's most liquid registration policy and plays an important role in the world's trading operations, At present, it occupies the second place in the domestic regular blockchain platform

3. Fire coin network

this is an earlier digital currency trading platform in China, mainly trading bitcoin. As the third instry of domestic regular blockchain platform, it is the trading platform with the largest bitcoin trading volume in China. Many new digital asset trading platforms have been developed under the company, For the future development of the foundation

This is a digital currency trading platform jointly established by some digital currency enthusiasts, and its founder is Zhao CHANGPENG. In fact, this trading platform didn't attract much attention at the beginning. With the continuous operation of the company and the founder's understanding of digital currency, this enterprise has become the top four domestic regular blockchain platforms, which shows the power of this platform

This is one of the most popular digital asset trading platforms in the world. There are many kinds of digital currencies for trading, and their main functions are cash out and derivative trading. They are well-known in the world's exchanges

5. The solutions are as follows:
1. Regularly clean the st in the computer, turn off the computer, open the chassis, use a hair dryer and blow with cold air< At ordinary times, 360 guard, Jinshan guard and other tools should be used to clean up the system garbage and temporary files generated by the Internet, and check and kill malicious

Italian software
3. The computer configuration is poor, so try to set the virtual memory as large as possible, and install anti-virus software with less resources, such as NOD32, or only one

auxiliary anti-virus software
4. Try to set the IP to static IP, which can rece the startup time of the computer
5. Don't put too many files and icons on the computer desktop, which will slow down the reaction of the computer. Try not to install the software on disk C
6. Regularly defragment the disk. Open the drive of my computer to defragment - properties - tools

select the disk to be defragmented. Open the "disk defragmenter" window - Analysis - defragmentation - the system will start to defragment

.

6. It depends on whether you invest. If you don't invest, you can make money by checking in every day. If you invest in the miner, the income will be higher.

7. Not yet, you can learn Java and big data, HTML5

8. Block head, transaction details, transaction counter and block size... Are these Shenma things
blockchain is the big ledger of bitcoin network, and each block is equivalent to a page in the ledger. What information is recorded in the "account book"? At present, each block of bitcoin mainly records data such as block head, transaction details, transaction counter and block size
"block header" contains all information except transaction information, mainly including the hash value of the previous block header, which is used to ensure that blocks are connected in sequence; Time stamp: record the generation time of the block; Random number: that is, the answer to the arithmetic problem of PK for all miners in the whole network; Difficulty target: score the difficulty coefficient of the arithmetic problem
"transaction details" records in detail the transferor, income party, amount and digital signature of the transferor of each transaction, which is the main content of each block
"transaction counter" describes the number of transactions contained in each block
"block size" refers to the size of each block data. Currently, each block is limited to 1MB, which does not rule out the possibility of expansion in the future.