区块链写入信息是指什么,区块链的信息写入

1. Is it possible that the information transmission of the blockchain itself is false?

Is it possible that the information transmission of the blockchain itself is false
1. The native characteristics of the blockchain, once included in the block, are irreversible and cannot be tampered with, and the information is true and valid. However, there is only one situation where it is false, that is, the information written in the initial attempt is false, causing the information in the stored block to be false < br />2. So the blockchain itself is just a technical means, and it fundamentally lies in the application of technology

2. What is the concept of blockchain

Literally understood , Blockchain includes two concepts: block and chain. The blockchain itself is composed of blocks, and the network built by linking different nodes together is the blockchain. The main function of the blockchain is to store information. Any information that needs to be saved can be written to the blockchain or read from it.

Each block stores: some valid record or transaction; information involving the block; links to the previous block and the next block through the hash of each block - which can be considered a block The unique code of the fingerprint.

Each block therefore has a specific and immovable position within the chain, as each block contains information from the hash of the previous block. The entire chain is stored in every network node that makes up the blockchain, so an exact copy of the chain is stored among all network participants.

Uses

Essentially, blockchain can be used to store any type of information that must remain intact and be more secure than going through a middleman. , decentralized and cheaper ways remain available. Additionally, since the stored information is encrypted, its confidentiality is guaranteed as only those with the encryption key can access it.

Using blockchain in healthcare. For example, health records can be consolidated and stored on the blockchain. This means that every patient's medical history is secure and, at the same time, available to every authorized doctor, regardless of the health center where the patient received treatment. Even the pharmaceutical industry could use this technology to authenticate medicines and prevent counterfeiting.

Blockchain is also very useful for managing digital assets and documents. The problem with digitization so far has been that everything is easily copied, but Blockchain allows you to record purchases, deeds, documents or any other type of online asset without it being counterfeited.

3. What technology does the blockchain apply to achieve this function?

The blockchain applies the following technologies to achieve this
The first is the consensus mechanism, a commonly used consensus mechanism Mainly include PoW, PoS, DPoS, PBFT, PAXOS, etc. Since there is no center in the blockchain system, there needs to be a preset rule to guide the nodes of all parties to reach an agreement on data processing. All data interactions must be carried out in accordance with strict rules and consensus;
The second It is cryptography technology. Cryptography technology is one of the core technologies of blockchain. The current blockchainMany classic algorithms of modern cryptography are used in chain applications, mainly including: hash algorithm, symmetric encryption, asymmetric encryption, digital signature, etc.
The third type is distributed storage. Blockchain is a distributed ledger on a peer-to-peer network. Each participating node will independently and completely store and write block data information. The advantages of distributed storage compared with traditional centralized storage are mainly reflected in two aspects: data information is backed up on each node to avoid data loss due to single point failure; data on each node is stored independently, effectively avoiding Malicious tampering with historical data.
Smart contracts: Smart contracts allow trusted transactions without a third party. As long as one party reaches the pre-set goals of the agreement, the contract will automatically execute the transaction. These transactions are trackable and irreversible. It has the advantages of transparency, credibility, automatic execution, and mandatory performance. Blockchain technology has many unique features that make it a unique invention and give it unlimited horizons to explore.

4. Questions about Bitcoin (1) How a transaction is written into the block

Due to the massive calculations set by humans, the area used to store Bitcoin transaction information is limited. The speed at which the blockchain generates new blocks. What I know about this speed is that it takes about 10 minutes to produce one.

You create a digital stream containing complete transaction information in some way and upload it to the network. This network can be understood as the Bitcoin node network, or it can refer to a node that can verify transactions. All uses of the word "network" in this article are interpreted as such.

Certain nodes verify that your transaction is legal, and then broadcast it to the entire Bitcoin node network. This broadcast is a process of continuous verification and re-broadcast. Until transaction A is received by most nodes in the network.

It should be understood that this process is only verification, not recording (confirmation).

What we call mining is to find a number that meets the requirements. This number represents a block just like an id.

After a transaction is confirmed in the network, it will be saved in the mining node to form a transaction pool. Miners need to select some high-priority transactions from the transaction pool to form an alternative block. , and mine according to this block. It is called a backup block because the transaction information stored in this block does not have an ID. Without an ID, it cannot be identified and cannot be approved.

In 04 Integrating Transactions & Building New Blocks, it is said that "after verifying transactions, each Bitcoin network node will add these transactions to its own memory pool". I think the node that verifies the transaction may be a non- Mining node, this node does not have the function of memory pool.

First of all, transaction fees are not fixed. To understand why it is not fixed, you need to understand a few issues:

There is a batch of transactions that need to be confirmed on the network. This batch of transactions exists in the hands of all miners. The recording work is performed by all miners according to their own recognized priorities, but the confirmation function is completed by one of them. This miner is the miner who successfully adds the block recording the transaction to the main chain. This miner: Completed the recording work, found a new block, and successfully added the block to the network.

Multiple factors such as time and transaction volume determine the priority of transactions, and transaction fees are one of them.

Based on the above description, summary:

The miner completes the transaction confirmation.

When you initiate a transaction, you may or may not specify a transaction fee. The amount of the transaction fee is directly related to the transaction confirmation time. If no miner is willing to record your transaction, theoretically your transaction cannot be written to the blockchain, which means it cannot be confirmed. The deal would never be completed.

Assume that your transaction will eventually be written to the blockchain and effectively confirmed.

No matter how your transaction is in the hands of other miners, first of all, your transaction meets the requirements of the miner who confirmed the transaction and is added to the alternative block instead of lying in the transaction pool.

This new block containing your transaction information is successfully added to the main chain, and the main chain is effectively extended. At this point your transaction record is effectively confirmed.

5. Explanation of the term blockchain

Blockchain is explained as follows:

Blockchain is actually equivalent to a disintermediated database, which is composed of It consists of a series of data blocks. Each of its data blocks contains information about a Bitcoin network transaction, which is used to verify the validity of the information and generate the next block.

In a narrow sense, blockchain is a chain data structure that combines data blocks in a sequential manner in chronological order, and is cryptographically guaranteed to be inextricable. Tamper-proof and unforgeable distributed ledger.

Type

Public Blockchain

Public Block Chains: Any individual or group in the world Transactions can be sent and effectively confirmed by the blockchain, and anyone can participate in its consensus process.

Public blockchain is the earliest blockchain and the most widely used blockchain. The virtual digital currencies of all major bitcoins series are based on public blockchains. There is only one such blockchain in the world. The blockchain corresponding to the currency.

Industry Block Chains

Industry Block Chains (Consortium Block Chains): Multiple pre-selected nodes are designated within a certain group as bookkeepers, and each block is generated by All preselected nodes jointly decide (preselectedNodes participate in the consensus process);

Other access nodes can participate in transactions, but do not participate in the accounting process (it is essentially still managed accounting, but it becomes distributed accounting. How to determine the number of pre-selected nodes? The bookkeeper of each block becomes the main risk point of the blockchain), and anyone else can conduct limited queries through the open API of the blockchain.

Private Block Chains

Private Block Chains: Only use the general ledger technology of the blockchain for accounting. It can be a company or an individual. With exclusive write access to the blockchain, this chain is not much different from other distributed storage solutions.

Traditional finance is trying to experiment with private blockchains, while public chain applications such as Bitcoin have been industrialized, and private chain application products are still being explored.

6. What is blockchain? A popular explanation of a new accounting method (you will understand after reading it carefully)

In the past two years, a new method of accounting has been circulated on the Internet. The financial model is "blockchain". I think many people still don't understand the meaning of this. After all, "blockchain" is still "advanced" to ordinary people in the past, so what is blockchain? What is the popular explanation? In fact, it is not as complicated as we imagined, so let me tell you what "blockchain" is and see what is special about this model!

What exactly is the "blockchain" that people often talk about? I believe that many people don’t know much about it, and most of the information they view on the Internet is “unclear”. In fact, it is easy to understand. So what is the popular explanation of blockchain? Fundamentally speaking, this model is a "decentralized" accounting method. So what is "decentralization"? All our current exchanges and communications on the Internet will actually be stored in a "centralized" server on a browser or APP. The other party can check our browsing information at will, and "decentralization" is convenient. This can be completely avoided.

Once information is written into the "blockchain", it cannot be tampered with, ensuring its authenticity and confidentiality. It can also avoid third-party platforms in transactions on the virtual market. Intervention, the transaction is directly completed by both parties, which saves a lot of procedures and time, and also ensures that information is not leaked, transparent and other security issues, and there is no possibility of data loss!

After reading the above introduction, everyone is interested in "DistrictIs there a new understanding of the "blockchain" model? Can't you understand? Let's take a look at it through a cartoon!

Fields of application of blockchain

The "blockchain" model can be applied in many fields. First of all, it must be financial. The first blockchain was born from Bitcoin. It can also be used in education, e-commerce, film and television, etc. With this new technology, all walks of life are now exploring this new field, hoping to have a foothold in the development of the future era!

7. What information does the blockchain record?

Block headers, transaction details, transaction counters and block sizes...are these all crazy things? The blockchain is the big ledger of the Bitcoin network, and each block is equivalent to a page in the ledger. . So what information is recorded in the "ledger"? Currently, each block of Bitcoin mainly records data such as block header, transaction details, transaction counter, and block size. The "block header" contains information other than transaction information. All information, mainly including the hash value of the previous block header: used to ensure that blocks are concatenated in order; timestamp: recording the generation time of the block; random number: the answer to the arithmetic problem that miners across the entire network PK together; difficulty target : The difficulty score of this arithmetic problem. "Transaction Details" records in detail the transferor, incomer, amount and digital signature of the transferor of each transaction, which is the main content in each block. "Transaction Counter" Describes the number of transactions included in each block. "Block size" indicates the size of each block data. Currently, each block is limited to 1MB, and the possibility of expansion in the future is not ruled out.

8. About storing information on blocks

How to store information on the blockchain: call the API provided by the blockchain platform

Generally, the blockchain platform will provide the corresponding Interfaces, such as RPC, JSON-RPC, HTTP, etc. Of course, different platforms have different degrees of friendliness

Some companies that specialize in APIs, such as BlockCypher, can provide friendly calling interfaces. Writing answers on mobile phones is not Very convenient, search for it

As for the stored content, I would like to add that in the file hash record chain, in addition to conventional cloud storage, there are also blockchain-based storage solutions for file entities, such as ipfs and storej. Wait