The significance of blockchain data encryption

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. Many relationships between people are based on trust, such as friend relationship, cooperation relationship, transaction relationship, etc
take trading activities as an example. In the past, the two sides who did not trust each other usually chose an intermediary to guarantee a transaction. In the mobile Internet era, we chose Taobao shopping because Alipay provided us with an intermediate guarantee. We chose to drop dripping because it provided us with information matching.
however, these intermediaries are centralized and have their own interests. Sometimes they are not so reliable and trustworthy. Theoretically, Alipay's centralization of accounting has been artificially falsified. Part of the reason for Didi's troubles is that they only think from their own standpoint
what blockchain does is the machine of trust, which replaces the role of trust intermediary with code, ensures the fairness and justice of the whole system through consensus mechanism and distributed accounting, and provides a trust without trust
for example, in the future, people can abandon the intermediate platform and realize point-to-point docking and free trading through blockchain. Shopping does not need to go through an intermediary, and taking a taxi does not need to go through Didi. In this way, we can really achieve "no middleman to earn the price difference" and rece the cost.

3.

- yinlian answer:

blockchain can realize the traceability and non tampering of data, because it is based on the distributed database established by cryptographic links, thus forming non tamperable data sources. Therefore, in the whole process of procts from proction to circulation, complete information records can be achieved, and comprehensive data information can be provided for regulatory authorities, so that they can more efficiently complete proct quality inspection and data interconnection and sharing. In this process, blockchain can solve four problems:

first, information can not be tampered, consensus can be reached and trust can be built. In the network node composed of each participant, data records are formed in the business process, and the information of proct logistics, warehousing and proction, including raw material source, processing and assembly, is stored in the blockchain network to provide data information of each link for regulatory departments, cooperative enterprises or institutions

Second, the process is open and transparent. In the process of business process, the proct's anti-counterfeiting and circulation can be realized by implanting an identification chip into the proct and registering it on the blockchain, so that it can have a digital identity, and then record all the information of the digital identity, such as source and flow, through the account book maintained jointly, so as to achieve the verification effect

Third, save cost and improve efficiency. Under the condition of confidentiality, the data records on the blockchain are stored, transmitted, verified and analyzed by the regulatory department, and transferred among different departments, so as to achieve unified voucher, whole process record and enterprise credit reference, which can effectively solve the problems of multi-party participation, information fragmentation and repeated audit in circulation

Fourthly, information sharing. The circulation of enterprise proct certification depends on the interconnection of public data resources among departments and institutions such as commerce, customs, quality inspection, instry and commerce, banking, etc. under the review environment of blockchain construction, all departments can obtain information synchronously, establish credit evaluation mechanism based on supply chain, and organically connect various supply chain platforms, so as to improve the credit rating, credit record, risk warning, risk management, etc Information disclosure and sharing of illegal and dishonest behavior

the disadvantages of traditional anti-counterfeiting traceability are very obvious, and anti-counterfeiting traceability has always been an important scenario in blockchain application, such as yinlian, which also starts from the anti-counterfeiting traceability scenario, hoping to build a commercial blockchain

compared with the traditional centralized anti-counterfeiting Traceability Technology, yinlian uses the underlying technology of blockchain, and the merchants proce their own anti-counterfeiting codes to remove the trust problem of cheating by the intermediate anti-counterfeiting merchants. The main process is as follows:

4. Blockchain encryption algorithm
asymmetric encryption algorithm is a function that converts the original plaintext file or data into a series of unreadable ciphertext codes by using an encryption key. The encryption process is irreversible. Only holding the corresponding decryption key can the encrypted information be decrypted into readable plaintext. Encryption enables private data to be transmitted through the public network under the condition of low risk, and protects the data from being stolen and read by the third party
the core advantage of blockchain technology is decentralization, which can realize point-to-point transaction, coordination and cooperation based on decentralized credit in a distributed system without mutual trust by means of data encryption, time stamp, distributed consensus and economic incentive, so as to solve the high cost and low cost of centralized institutions Low efficiency and data storage insecurity provide solutions
the application fields of blockchain include digital currency, token, finance, anti-counterfeiting traceability, privacy protection, supply chain, entertainment, etc. with the popularity of blockchain and bitcoin, many related top domain names have been registered, which has a great impact on the domain name instry.

5. To understand the principle of blockchain thoroughly, we must understand it systematically from its birth and development, so as to distinguish the principle of blockchain more clearly from multiple perspectives. Block chain technology refers to the technical solution of collective maintenance of a reliable database in a centralized way in the past. In this technical scheme, blocks are associated by cryptography. Each data block contains all the data information of the system in a certain period of time, and generates a digital signature to verify the validity of the information, and links to the next data block to form a main chain< br />
Block is a record in the blockchain, which contains and confirms the transactions to be processed< br />
mining refers to the formation of new blocks through calculation. It is a process in which the supporters of the transaction use their own computer hardware to do mathematical calculation for the network to confirm the transaction and improve the security. Take bitcoin as an example: the transaction supporter (miner) runs bitcoin software on the computer and constantly calculates the complex cryptography problems provided by the software to ensure the transaction. As a reward for their service, miners can get the Commission included in the transaction they confirm, as well as the newly created bitcoin< br />
Peer to peer network is a system that allows a single node to interact directly with other nodes, so that the whole system can operate like an organized collective. Take bitcoin: the network is built in such a way that each user is spreading the transactions of other users. And importantly, banks or other financial institutions are not required as third parties< br />
Hash is a classical technology in cryptography, which transforms the input of any length into the output of fixed length composed of letters and numbers through Hassi algorithm< br />
Digital signature is a mathematical mechanism that allows people to prove ownership< br />
Private key is a secret data block that proves that you have the right to consume e-money from a specific wallet. It is realized by digital signature< br />
Dual consumption refers to the user's illegal attempt to pay e-money to two different payees at the same time, which is one of the biggest risks of e-money< br />
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The origin of blockchain: an underlying technology supporting bitcoin

The concept of blockchain was first proposed in bitcoin: a peer-to-peer electronic cash system by Satoshi Nakamoto in late 2008. In this paper, block chain technology is the basic technology to build bitcoin data structure and transaction information encryption transmission, which realizes the mining and transaction of bitcoin. Nakamoto believes that: first, the mode of using third-party organizations to process information has the inherent weakness of lack of trust between points. In order to guard against their customers, businesses will ask customers for completely unnecessary information, but still can not avoid certain fraud; Second, the existence of intermediaries increases the transaction cost and limits the practical minimum transaction scale; Third, digital signature itself can solve the problem of e-money identity. If the third party support is needed to prevent double consumption, the system will lose value. Based on the above three existing problems, Nakamoto Cong has created bitcoin on the basis of blockchain technology< br />
On January 3, 2009, Nakamoto proced the first bitcoin block in the world, genesis block, and excavated 50 bitcoins< br />
On May 21, 2010, Florida programmers bought $25 worth of pizza coupons with 10000 bitcoin, which gave birth to the first fair exchange rate of bitcoin< br />
In July 2010, the first bitcoin platform was established, with a surge in new users and prices< br />
In February 2011, the price of bitcoin reached US $1 for the first time. Since then, exchange trading platforms with British pound, Brazilian real and Polish zloty have opened< br />
In 2012, ripple released that as a digital currency, it uses blockchain to transfer foreign exchange of various countries< br />
In 2013, bitcoin soared. The U.S. Treasury Department has issued the regulations on the personal management of virtual currency to clarify the definition of virtual currency for the first time< br />
In 2014, the mining machinery instry chain represented by China became more and more mature. In the same year, the U.S. it community realized the cross era innovation significance of blockchain in the digital field< br />
In 2015, the US Nasdaq Stock Exchange launched LINQ, a digital ledger technology based on blockchain, to record trading and issue stocks

the principle of blockchain can be understood clearly from each application case, and the application of blockchain principle is becoming more and more popular. Recently, Citigroup, Mitsubishi UFJ Financial Group, UBS and Deutsche Bank will also apply "blockchain" technology to build a fast, convenient and efficient blockchain Low cost trading system. In addition to the financial field, blockchain technology has also begun to be applied to the protection of intellectual property rights, notarization by lawyers, online games and other fields where there is a need for transparent information disclosure and permanent records.