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Blockchain biometric technology
Publish: 2021-05-17 21:36:40
1. blockchain does not belong to any instry. Blockchain is a new application mode of computer technology, such as distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and so on. In a narrow sense, blockchain is a kind of chain data structure that combines data blocks in a sequential way according to the time sequence, and it is a distributed account book that can not be tampered with and forged by means of cryptography.
2. First of all, we can take a look at the official website explanation of blockchain technology. In a narrow sense, blockchain is a kind of chain data structure that combines data blocks in a sequential way 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
as we all know, blockchain technology is an independent underlying architecture from bitcoin system. From the perspective of architecture model, it is a set of distributed ledger, which is naturally used for bookkeeping
in the blockchain technology, if you want to generate accounting records, you need to have the transaction and flow of funds. Therefore, in the initial blockchain technology, the cryptocurrency corresponding to the main network is used as circulation goods, and the circulation transaction records of cryptocurrency between the accounts of the main network of the blockchain will be recorded on the main network
different from other transaction record databases, transaction records on the main network of blockchain technology will be recorded on all block nodes (i.e. all data blocks) in the main network, which is the so-called decentralization principle. That is to say, in blockchain technology, there is no central database to store all records, Every block on the chain has the transaction data of the whole chain, that is to say, every data block is the center
another feature of blockchain technology is that it can't be tampered with, because every transaction on the blockchain will be recorded in all blocks on the chain, so no single data block can change the record. Even if you change it, all other data blocks will also record real data, and each group of data can be traced back to the first time
because of these characteristics of blockchain technology, after the advent of bitcoin, blockchain has also attracted a lot of attention, and many people also began to want to use blockchain technology to make a centerless, traceable and unchangeable data, so as to ensure the credibility of the data
however, blockchain technology also faces many problems, such as single application scenario, non modifiable original error data, non recoverable currency stolen by hackers, etc.
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
as we all know, blockchain technology is an independent underlying architecture from bitcoin system. From the perspective of architecture model, it is a set of distributed ledger, which is naturally used for bookkeeping
in the blockchain technology, if you want to generate accounting records, you need to have the transaction and flow of funds. Therefore, in the initial blockchain technology, the cryptocurrency corresponding to the main network is used as circulation goods, and the circulation transaction records of cryptocurrency between the accounts of the main network of the blockchain will be recorded on the main network
different from other transaction record databases, transaction records on the main network of blockchain technology will be recorded on all block nodes (i.e. all data blocks) in the main network, which is the so-called decentralization principle. That is to say, in blockchain technology, there is no central database to store all records, Every block on the chain has the transaction data of the whole chain, that is to say, every data block is the center
another feature of blockchain technology is that it can't be tampered with, because every transaction on the blockchain will be recorded in all blocks on the chain, so no single data block can change the record. Even if you change it, all other data blocks will also record real data, and each group of data can be traced back to the first time
because of these characteristics of blockchain technology, after the advent of bitcoin, blockchain has also attracted a lot of attention, and many people also began to want to use blockchain technology to make a centerless, traceable and unchangeable data, so as to ensure the credibility of the data
however, blockchain technology also faces many problems, such as single application scenario, non modifiable original error data, non recoverable currency stolen by hackers, etc.
3.
From the perspective of technology and architecture, I will tell you my understanding of blockchain in common language
what is blockchain? In a word, blockchain is a storage system. To be more specific, blockchain is a distributed storage system without an administrator and each node has all the data
What are the common storage systems like
first, how to ensure high availability
the common storage system usually uses "rendancy" to solve the problem of high availability. As shown in the figure above, if the data can be copied into several copies and rendant to multiple places, high availability can be guaranteed. The data in one place is hung, and there is data in other places. For example, the master-slave cluster of MySQL is the same principle, and the raid of disk is also the same principle
two points need to be emphasized in this place are: data rendancy often leads to consistency problems
1. For example, in the master-slave cluster of MySQL, there is actually a delay in reading and writing, which means there is a inconsistency in reading and writing in a short period of time. This is a side effect of data rendancy
The second point is that data rendancy often reces the efficiency of writing, because data synchronization also consumes resources. If you add two slave libraries, the write efficiency will be affected. The common storage system is to use rendancy to ensure the high availability of dataso the second question, ordinary storage system, can write more
the answer is yes, for example, take this graph as an example:
in fact, MySQL can do a master-slave synchronization of al masters, master-slave synchronization of al masters, two nodes can be written at the same time. If you want to do a multi room multi live data center, in fact, multi room multi live data synchronization. What we should emphasize here is that multi-point writing often leads to the consistency problem of writing conflicts. Take MySQL as an example, suppose that the attribute of a table is self incrementing ID, then the data in the database is 1234 now. If one of the nodes writes and inserts a piece of data, it may become 5, and then these 5 pieces of data are synchronized to another master node, Before synchronization, if another write node inserts a piece of data, a piece of data with self incrementing ID of 5 will be generated. Then, after the generation, synchronize to another node, and the synchronized data will conflict with the two local 5's after it arrives, which will lead to synchronization failure and write consistency conflict. This problem will occur in the case of multi-point writing
how to ensure consistency in multi-point writing
the reform "Swan class" gives you more technical work
4. Introction to seven core technologies of blockchain operation on January 15, 2018
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 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.
5. 1、 Decentralization:
blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain< Second, openness:
the foundation of blockchain technology is open source. In addition to the private information of all parties to the transaction is encrypted, the data of blockchain is open to all. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent< Third, independence:
based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention< Fourth, security:
as long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily controlled and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes
5. Anonymity:
unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and information transmission can be carried out anonymously
Digital China is the first major development strategy explicitly put forward in the report of the 19th National Congress of the Communist Party of China. The application of digital technology represented by cloud computing, big data and mobile Internet is no longer limited to the economic field, but widely penetrated into all aspects of public services, social development and people's life, which requires macro coordination, overall control and integrated development
with the deepening of a new round of scientific and technological revolution and instrial change, the tide of digital economy in the world is unstoppable. The development of digital economy has become a global consensus, known as the key to the fourth instrial revolution
adhering to the connotation of the University of nice's world inclusive humanistic spirit, always embracing change, standing up to the tide, conforming to the development trend of the digital economy era, and integrating the essence of Chinese and Western cultural thinking, the University of nice's doctor of blockchain and digital economy management (DDE) came into being
based on this, we can enable the managers of digital economy instry to have global vision and global integration thinking, integrate knowledge, operate digital economy intelligently, promote the sustainable development of the instry, and contribute to the community of human destiny. Therefore, DDE project will cooperate with colleagues in the field of digital economy
if you have MBA related questions, you are welcome to contact me personally&# 180;&# 65381;&# 7447;&# 65381;` ) Bixin~~~~
blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain< Second, openness:
the foundation of blockchain technology is open source. In addition to the private information of all parties to the transaction is encrypted, the data of blockchain is open to all. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent< Third, independence:
based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention< Fourth, security:
as long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily controlled and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes
5. Anonymity:
unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and information transmission can be carried out anonymously
Digital China is the first major development strategy explicitly put forward in the report of the 19th National Congress of the Communist Party of China. The application of digital technology represented by cloud computing, big data and mobile Internet is no longer limited to the economic field, but widely penetrated into all aspects of public services, social development and people's life, which requires macro coordination, overall control and integrated development
with the deepening of a new round of scientific and technological revolution and instrial change, the tide of digital economy in the world is unstoppable. The development of digital economy has become a global consensus, known as the key to the fourth instrial revolution
adhering to the connotation of the University of nice's world inclusive humanistic spirit, always embracing change, standing up to the tide, conforming to the development trend of the digital economy era, and integrating the essence of Chinese and Western cultural thinking, the University of nice's doctor of blockchain and digital economy management (DDE) came into being
based on this, we can enable the managers of digital economy instry to have global vision and global integration thinking, integrate knowledge, operate digital economy intelligently, promote the sustainable development of the instry, and contribute to the community of human destiny. Therefore, DDE project will cooperate with colleagues in the field of digital economy
if you have MBA related questions, you are welcome to contact me personally&# 180;&# 65381;&# 7447;&# 65381;` ) Bixin~~~~
6. Recently, the hottest investment is bitcoin. From financial tycoons to ordinary people, they are talking about the surge of bitcoin. Bitcoin is a kind of blockchain. I believe there are still many people who don't know much about blockchain, so today we will explain in detail what blockchain is? How to search blockchain technology patents? What is blockchain? More than 10000 years ago, human beings began to learn to use shells as an intermediary for exchanging materials, and later developed into currency. With the development of network, the circulation of digital currency has graally replaced the traditional currency, and now people's payment methods have undergone unprecedented changes. The emergence of encrypted electronic currencies such as bitcoin, Ethereum and litecoin has further prompted the whole financial system to face up to and start thinking about transformation. However, there is an important technical support behind the development of encrypted e-money which is not affected by the traditional financial system;; Block chain. Blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. The so-called consensus mechanism is a mathematical algorithm to establish trust and obtain interests between different nodes in the blockchain system. How to search blockchain technology patents Blockchain Revolution & sup1; A book has mentioned that blockchain is a public database, which records all transaction information and can effectively prevent tampering; It is a distributed system, which does not store on a specific server or node, but scattered in countless nodes on the network, each node only retains part of the information; It is a kind of consensus agreement, which follows a mechanism together. As the underlying technology behind cryptocurrency, including identity authentication, medical record preservation, market forecasting, asset trading, etc., blockchain is graally applied. To observe the patent applications related to global blockchain technology, the author suggests that you should refer to the definitions of block chain, distributed ledger and smart contract to expand your search conditions, rather than only limited to the patents using the word block chain. What is blockchain? How to search blockchain technology patents? If you have more questions about patent inquiry, you can continue to pay attention to Bajie intellectual property or contact us by telephone.
7. Anti counterfeiting traceability through the traditional two-dimensional code technology has been able to solve the problem, the pain is that the anti-counterfeiting data stored in the central structure, easy to tamper with, credibility is not strong. It happens that the characteristics of blockchain are very consistent with anti-counterfeiting traceability. Let's review the four characteristics of blockchain application
four characteristics of blockchain application:
first, decentralization: blockchain consists of many nodes to form an end-to-end network, and there is no centralized equipment and management organization
Second, tamper proof: the modification of the database by a single node or even multiple nodes cannot affect the database of other nodes, unless more than 51% of the nodes in the whole network can be controlled to modify at the same time, which is almost impossible
Third, transaction transparency: the operation rules of the blockchain are open and transparent, and all the data information is also open, Each transaction is visible to all nodes
4. Traceability: each transaction in the blockchain is connected with two adjacent blocks by password method, so it can trace back to the origin and development of any transaction.
four characteristics of blockchain application:
first, decentralization: blockchain consists of many nodes to form an end-to-end network, and there is no centralized equipment and management organization
Second, tamper proof: the modification of the database by a single node or even multiple nodes cannot affect the database of other nodes, unless more than 51% of the nodes in the whole network can be controlled to modify at the same time, which is almost impossible
Third, transaction transparency: the operation rules of the blockchain are open and transparent, and all the data information is also open, Each transaction is visible to all nodes
4. Traceability: each transaction in the blockchain is connected with two adjacent blocks by password method, so it can trace back to the origin and development of any transaction.
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