Blockchain technology Yang Dong
blockchain refers to the technical solution of collective maintenance of a reliable database through centralization and distrust in the past, and it is a technical way for the whole people to participate in bookkeeping. Previous bookkeeping methods were all centralized and needed centralized intermediary, whether it was traditional government, financial institutions, notarization institutions or emerging e-commerce platform and online payment platform
in economic hypothesis, information is sufficient. In fact, it is precisely because of insufficient information that there are very large intermediaries. The existence of intermediaries increases the transaction cost and raises the transaction threshold. In essence, blockchain technology is a large-scale collaboration tool. It makes direct value transfer possible by using pure technology for the first time, and continues the trend of Internet decentralization and disintermediation. Disintermediated blockchain technology will greatly subvert the information intermediary instry
blockchain technology is the basic technology for building bitcoin data structure and encrypted transmission of transaction information, which realizes the issue and transaction of bitcoin. The core of blockchain technology is that all the current participating nodes jointly maintain the transaction and database, so that the transaction is based on the principle of cryptography rather than trust, so that any agreed parties can directly carry out payment transactions without the participation of a third party
technically, a block is a data structure for recording transactions, reflecting the capital flow of a transaction. In the system, the transaction blocks are connected to form a main chain, and all the nodes participating in the calculation record the main chain or part of the main chain
a block contains the following three parts: transaction information, hash formed by the previous block and random number. Transaction information is the task data carried by the block, including the private keys of both parties, the number of transactions, the digital signature of electronic currency, etc; The hash hash formed by the previous block is used to connect the blocks and realize the sequence of past transactions; Random number is the core of the transaction. All nodes compete to calculate the answer of the random number. The node that gets the answer the fastest generates a new block and broadcasts it to all nodes for updating, so as to complete a transaction.
1. Blockchain links
as the name suggests, blockchain is a chain composed of blocks. Each block is divided into block head and block body (including transaction data). The block head includes the prevhash value (also known as hash value) of the previous block used to realize the block link and the random number (nonce) used to calculate the mining difficulty. The hash value of the previous block is actually the hash value of the head of the previous block, and the random number calculation rule determines which miner can obtain the right to record the block
2. Consensus mechanism
blockchain is accompanied by the birth of bitcoin, which is the basic technology architecture of bitcoin. Blockchain can be understood as an Internet-based decentralized accounting system. A decentralized digital currency system like bitcoin requires the consistency of accounting of honest nodes without a central node, which needs blockchain to complete. Therefore, the core of blockchain technology is a consensus mechanism to reach a consensus on the legitimacy of transactions between indivials without mutual trust without central control
there are four main types of consensus mechanisms in blockchain: pow, POS, dpos and distributed consistency algorithm
3. Unlocking script
script is an important technology to realize automatic verification and contract execution on blockchain. Every output of every transaction does not point to an address in the strict sense, but to a script. A script is like a set of rules that constrain how the receiver can spend the asset locked on the output
the validation of transactions also depends on scripts. At present, it depends on two kinds of scripts: Lock script and unlock script. Locking script is a condition added to the output transaction, which is realized by a script language and located in the output of the transaction. The unlocking script corresponds to the locking script. Only when the conditions required by the locking script are met can the assets corresponding to the script be spent, which is located in the input of the transaction. Many flexible conditions can be expressed by script language. Interpretation script is similar to the "virtual machine" in our programming field, which runs in every node of the blockchain network in a distributed way
4. Transaction rules
blockchain transaction is not only the basic unit of a block, but also the actual effective content recorded by the blockchain. A blockchain transaction can be a transfer, or the deployment of smart contracts and other transactions
as far as bitcoin is concerned, a transaction refers to a single payment transfer. The transaction rules are as follows:
1) the input and output of the transaction cannot be empty
2) for each input of a transaction, if its corresponding utxo output can be found in the current transaction pool, the transaction will be rejected. Because the current transaction pool is the transaction not recorded in the blockchain, and each input of the transaction should come from the confirmed utxo. If it is found in the current trading pool, it is Shuanghua trading
3) for each input in a transaction, the corresponding output must be utxo
4) each input unlocking script must verify the compliance of the transaction together with the corresponding output locking script
5. Transaction priority
the priority of blockchain transaction is determined by the blockchain protocol rules. For bitcoin, the priority of a transaction to be included in a block is determined by the time when the transaction is broadcast to the network and the amount of the transaction. With the increase of transaction broadcast time on the network and the increase of transaction chain age, the priority of transaction will be improved and eventually be included by the block. For Ethereum, the priority of the transaction is also related to the transaction fee that the publisher is willing to pay. The higher the transaction fee that the publisher is willing to pay, the higher the priority that the transaction is included in the block
6. Merkle proof
the original application of Merkle proof is bitcoin, which was described and created by Satoshi Nakamoto in 2009. Bitcoin blockchain uses Merkle proof to store transactions in each block. So that the transaction can not be tampered with, but also easy to verify whether the transaction is included in a specific block
7. RLP
RLP (recursive length prefix) is one of the main encoding methods of object serialization in Ethereum. Its purpose is to encode the sequence of arbitrary nested binary data.
1. Blockchain is a distributed database (system) placed in a non secure environment
2. The blockchain uses cryptography to ensure that the existing data cannot be tampered with
3, the blockchain uses consensus algorithm to reach consensus on new data
the system with the above three properties is blockchain.
A: application fields of blockchain technology
I. financial field
blockchain has great potential application value in international exchange, letter of credit, equity registration, stock exchange and other financial fields
Second, the Internet of things and logisticsblockchain can also be naturally combined in the field of Internet of things and logistics
through the blockchain, we can rece the logistics cost, trace the proction and transportation process of goods, and improve the efficiency of supply chain management
Third, in the field of public service, blockchain is closely related to people's proction and life in the fields of public management, energy and transportation. However, the centralization of these fields also brings some problems, which can be transformed by blockchain Fourthly, in the field of digital right, through blockchain technology, works can be authenticated to prove the existence of text, video, audio and other works and ensure the authenticity and uniqueness of ownership In the field of insurance, insurance institutions are responsible for fund collection, investment and claim settlement, and often have higher management and operation costs Sixth, the data stored on the public welfare fieldblockchain is highly reliable and tamperable, which is naturally suitable for social public welfare scenarios
at present, the traditional database is centralized recording and storage. Even for remote disaster recovery and cloud storage, it only changes the storage location from one place to multiple places, from local to cloud. If there is a problem with the central server, the disaster recovery database will stop updating data; The blockchain database is distributed record, distributed storage and distributed propagation. Each information is transmitted by a single node to all other nodes in the whole network. Each node is responsible for data recording and storage. No centralized or third-party organization is responsible for management. If one node has problems, other nodes will continue to update and store data, Through the way of decentralization, the stable operation of the system is maintained, and the information is complete and reliable.
Shaoyang sanlongtong blockchain Technology Co., Ltd. is another limited liability company incorporated on October 18, 2018, with its registered address at the 4th floor of beehive maker, Shaoyang Economic Development Zone, Shaoyang City, Hunan Province
the unified social credit code / registration number of Shaoyang sanlongtong blockchain Technology Co., Ltd. is 91430500ma4q1kwr2e, and the enterprise legal person is long Zhiqiang. At present, the enterprise is in business
the business scope of Shaoyang sanlongtong blockchain Technology Co., Ltd. is: information technology consulting services; Research, development and application of blockchain technology; Blockchain technology consultation and technology transfer; Supply chain management and service; Internet of things technology services; Research and development of Internet of things technology; Internet of things technology consulting; Research and development of big data processing technology; The development and construction of e-commerce platform; Network integration system construction, maintenance, operation, leasing; The first kind of value-added telecommunication service is domestic multi-party communication service Without approval, it is not allowed to engage in P2P online lending, equity crowdfunding, Internet insurance, asset management, and cross-border Internet financial services such as finance, third-party payment, virtual currency trading, ICO, illegal foreign exchange, etc. (projects that need to be approved according to law can only be carried out with the approval of relevant departments)
check more information of Shaoyang sanlongtong blockchain Technology Co., Ltd. through aiqicha
in the narrow sense, blockchain is a kind of chain data structure composed of data blocks connected in sequence according to the time sequence, and it is a distributed account book that can not be tampered with and forged by means of cryptography
broadly speaking, blockchain technology is a new distributed infrastructure and computing paradigm, which uses blockchain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, uses cryptography to ensure the security of data transmission and access, and uses intelligent contract composed of automated script code to program and operate data.