区块链哈希值怎么查看,区块链中的哈希算法

区块链哈希值是一种算法，用于记录和确认区块链数据的完整性。它是一种数字摘要，可以用来验证数据，确保数据的完整性和安全性。下面介绍区块链哈希值拓展的三个相关关键词：

SHA256算法：SHA256是一种常用的哈希算法，它可以将任意长度的数据转换成256位（32个字节）的散列值，这种散列值是唯一的。它是一种单向函数，无法从散列值反向推算出原始数据，因此它可以用来验证数据的完整性和安全性。SHA256算法被广泛应用于区块链技术中，用来记录和确认区块链数据的完整性。

RSA算法：RSA算法是一种公钥加密算法，它使用一对公钥和私钥来加密和解密数据，以保证数据的安全性。RSA算法可以用来签署和验证数字签名，以确保数据的完整性和安全性。它也可以用来加密和解密数据，以防止数据被窃取。RSA算法也被广泛应用于区块链技术中，用来记录和确认区块链数据的完整性。

AES算法：AES算法是一种对称加密算法，它可以将任意长度的数据转换成128位（16个字节）的散列值，这种散列值是唯一的。AES算法可以用来加密和解密数据，以防止数据被窃取。它也可以用来签署和验证数字签名，以确保数据的完整性和安全性。AES算法也被广泛应用于区块链技术中，用来记录和确认区块链数据的完整性。

以上就是区块链哈希值拓展的三个相关关键词：SHA256算法、RSA算法和AES算法的介绍，它们都可以用来验证数据的完整性和安全性，以确保区块链数据的完整性。

㈠ What is the hash value in the blockchain?

The hash value in the blockchain is to convert an input string of any length into a password and make a fixed output the process of. The hash value is not a "password" and the original data cannot be retrieved by decrypting the hash, it is a one-way cryptographic function.

In a blockchain, each block has the hash of the previous block. When any data in the current block is changed, the hash of the block will be changed, which will affect the previous block because it has the address of the previous block. For example, if there are only two blocks, one is the current block and the other is the parent block. The current block will have the address of the parent block, and if the data in the current block needs to be changed, the parent block will also need to be changed.

A cryptographic hash function needs to have the following key characteristics to be considered useful

1. Each hash The values ​​are all different.

2. For the same message, the same hash value is always generated.

3. It is impossible to determine the input based on the hash value.

4. Even a small change to the entire hash value of the input will be changed.

㈡ What does the hash value in the blockchain mean?

If you know something about the blockchain field, then you must have heard of the hash value. Maybe we are When browsing blockchain information, we often see hash values, but if we ask us to talk about what a hash value is, we may not be able to explain it clearly. I know that although many people have been in the currency circle for a long time, they still have a partial understanding of some concepts in the blockchain field, and they are aware but not completely clear. In fact, hashing is a method of compressing information. We can use hashing to compress a long paragraph of text into a small piece of garbled code. So what does the hash value in the blockchain mean? Now let me explain it to you in detail.

Hashing is the process of converting an input string of any length into a password and producing a fixed output. The hash value is not a "password", we cannot retrieve the original data by decrypting the hash, it is a one-way encryption function.

What is blockchain hash? If you are just beginning to understand blockchain, you need to understand it together with the concept of "block". Each block contains data information, the hash value of this block and the hash value of the previous block. The data information in the block mainly includes the addresses of both parties to the transaction, the number of transactions, and transaction time information. The hash value is the key to finding the blocks and then understanding the information of these blocks. The above is the meaning of hashing in the blockchain.

The blockchain encrypts the transaction information in a transaction block through a hash algorithm and compresses the information into a hash string consisting of a series of numbers and letters. Jinwowo Group analyzes the role of its hash algorithm as follows: the hash value of the blockchain can uniquely and accurately identify ablock, any node in the blockchain receives the hash value of this block through simple hash calculation. The calculated hash value does not change, which means that the information in the blockchain has not been tampered with.

In blockchain, each block has the hash value of the previous block, and the previous block is called the parent block of the current block, if considering the parent block there is a current block. It will have the hash of the previous block i.e. the parent block.

In a blockchain, each block has a hash of the previous block. When we change any data in the current block, the hash of the block will be changed, which will affect the previous block because it has the address of the previous block. For example, if we only have two blocks, one is the current block and one is the parent block. The current block will have the address of the parent block. If you need to change the data in the current block, you also need to change the parent block. When there were only two data blocks, it was easy to change the data, but now when we implement it in the blockchain, 2020-01-24 12:32 614272 blocks have been mined and the hash of the 614272(th) block The value is 00000000000000000007. If we want to change the data in the current block 614272(th), the hash address of block 614271 must change, but the hash of block 614271 is impossible to change, so this is why the blockchain is called immutable and the data can Believe it. The first block of the blockchain is called the origin block. You can see from this origin block how many blocks have been mined until now.

If we make a small change in any part of the input, there will be a big change in the output, see the example below for more understanding. Hash values ​​are the core foundation and most important aspect of the immutable and deterministic potential of blockchain technology. It preserves the authenticity of the data recorded and viewed, as well as the integrity of the blockchain as a whole.

#BTC[超话]# #digital currency# #欧易OKEx#

㈢ When withdrawing coins from the wallet to the exchange, is there a hash value and how to check it

Hash function refers to a function that maps the key key value of an element in a hash table to the storage location of the element. The elements in the hash table are determined by the hash function. The keyword K of the data element is used as an independent variable, and the value calculated through a certain functional relationship (called a hash function) is the storage address of the element. Expressed as: Addr = H(key).
Response time: 2021-07-05. For the latest business changes, please refer to the official website of Ping An Bank.
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㈣ Where to check the drcfx hash value

official website.
1. drcfx is a blockchain technology. The hash value is the value calculated by the hash function (also known as hash function/hash algorithm).
2. Search the drcfx official website with your browser to view its hash value.

㈤ How can a novice understand the hash calculation in the blockchain in seconds

​ How can a novice understand the hash calculation in the blockchain in seconds

When I was learning about blockchain, I found that there was a word that appeared repeatedly like a ghost, "Hash", written in English as "HASH".

That classmate who said he had diarrhea, get out of here! !

This "hash" is said to be a function derived from cryptography. Try searching and you will find a bunch of papers, either horizontal or vertical, tables or pictures, and another Hei doesn't understand xyzabc. Brother, I just want to understand the basic knowledge of blockchain. Why is it so difficult for me? ! My longest password is 123456, and the more complicated one is 654321. When it is the most complicated, add an a at the end. The complicated password you wrote to me obviously feels like my brain power is being drained, and my only brain cells are dying in batches! In order to let novice students like me understand this, I reluctantly tried to explain hash calculation in a fool's language, not seeking the most accurate but the simplest and easiest to understand. Let’s start:

# 1. What is a hash algorithm

## 1. Definition: A hash algorithm converts a string of any length into a fixed-length character string.

It can be seen from here that it can be understood as inputting a string of numbers to the "hash operation", and it will output a string of numbers**.

If we define the "increment by one algorithm" ourselves, then if we input 1, it will output 2; if we input 100, it will output 101.

If we define the "uppercase algorithm" ourselves, then input "abc" and output "ABC".

Haha, don’t hit me yet! This is really just the concept of a function.

## 2. Features:

What are the characteristics of this hash algorithm compared with my "increment by one algorithm" and "uppercase algorithm"?

1) **Certainty, fast calculation**: The result is the same no matter how you calculate it, and the calculation efficiency is high.

2) **Irreversible**: It means knowing that the output cannot deduce the value of the input.

3) **Unpredictable results**: Just change the input a little, and the results will be completely irregular.

In short, this hash operation is a black box and a good helper for encryption! You said "11111", it will encrypt it to "" for you, and if you say "11112", it will encrypt it to "" for you. Anyway, the input and output are in the sky and the earth, even if the input is related, the two outputs are not related.

# 2. The use of hash operations in the blockchain

## 1. Data encryption

**Transaction data is encrypted through hash operations, and Write the corresponding hash value into the block header**. As shown in the figure below, a block header contains the hash value of the previous block and the hash value of the next block.

1 ), **Identify whether the block data has been tampered with**: The hash value of the blockchain can uniquely and accurately identify a block. Any node in the blockchain can obtain the block’s value through simple hash calculation. Hash value, the calculated hash value has not changed, which means that the information in the blockchain has not been tampered with.

2), **Concatenate each block into a blockchain** : Each block contains the hash value of the previous block and the value of the next block, which is equivalent to linking to the end of the previous block through the hash value of the previous block, and through the hash value of the next block. The hash value is linked to the head of the next blockchain, naturally forming a chain-structured blockchain.

## 2. Encrypted transaction address and hash

In the block header in the picture above, there is a hash value of Merkle root. What is it used for?

First, understand what Merkle root is? It is a The root of the binary tree structure. What is a binary tree? What is a root? Just look at the picture below and you will know. One divided into two, two divided into four, four divided into eight can be divided continuously and it is called a binary tree. The root is the top node, which is called the root.

How does the data of this root come from? After the hash value of each transaction in a block is obtained, the hash value is then hashed again, and then hashed again. Hash, until the top value.

What has been done for a long time? What is the use?

1), **Quickly locate each transaction **: Since transactions are stored linearly, locating a transaction requires traversal, which is inefficient and time-consuming. Through such a binary tree, you can quickly locate the transaction you are looking for.

For example Inappropriate example: How to find an arbitrary integer between 0 and 100? (Assume the answer is 88) A better way is to ask: 1. Is it larger or smaller than 50? 2. Is it larger or smaller than 75? 3. Is it bigger or smaller than 88? You can quickly locate the answer with just a few questions.

2), **Verify whether the transaction data has been tampered with**: From the transaction to the hash value of each binary tree , any numberAny change in the word will lead to a change in the Merkle root value. At the same time, if an error occurs, you can quickly locate the error.

## 3. Mining

There is a parameter in our block header called **random number Nonce. The process of finding this random number is called "mining" **! Any machine on the network only needs to find a suitable number to fill in the Nonce position of its own block, so that the hash value of the data in the 6 fields (80 bytes) of the block header is more than 18 Starting with 0, whoever found "the gold"! Since there is no way for us to write a number that satisfies 18 zeros in advance and then infer Nounce, the only way is to try one by one starting from 0 to see if the result meets the requirements. If not, try the next one until it is found.

What are you looking for this number for? What's the use of doing this?

1), **Fairly find the computer with the strongest computing power**: This is a bit like I have a sand here, and let me tell you that it is the same as a grain of sand on that beach, you Find the same ones. The feasible way is to pick up each pill and compare them! Then the person with the fastest speed is most likely to reach the sand first. This is the so-called "proof of work POW". If you find this sand first, I think you will compare the most and do the most work.

2) **Dynamic adjustment of difficulty**: In order to ensure that a block is produced in 10 minutes, Bitcoin will calculate the difficulty of finding this nonce number every 2016 blocks (2 weeks) , if the average time of these 2016 blocks is less than 10 minutes, increase the difficulty, and if it is more than ten minutes, decrease the difficulty. In this way, no matter how the mining computing power of the entire network changes, the random number nonce can be calculated within 10 minutes.

# 3. What are the hash operations?

Having said so many hash operations, it seems that hash operations are just one type, but in fact they are not! As hash operations in cryptography, many schools have been derived from the continuous development. After watching "Man Tou Bao", I still feel that the internal mechanism is too complicated. I will list it as follows for now, so that novices can have an impression and know what is going on.

It can also be seen from the table below that hash operations are also constantly developing. There are various algorithms, and various applications are also flexibly applying single or multiple algorithm. In the Bitcoin system, hash operations basically use the SHA256 algorithm, while Litecoin uses the SCRYPT algorithm. Quark and Dash use many algorithms in series layer by layer. Heavycoin (HAV) However, the following algorithms are connected in parallel, each takingMix some to use. The POW phase of Ethereum uses the ETHASH algorithm, and ZCASH uses EQUIHASH.

It should be noted that various algorithms for hash operations are constantly being upgraded and improved, and the algorithms used by various currencies are not static and are also being continuously optimized.

**Summary**: Hash operations are widely used in various blockchain projects. Taking Bitcoin as an example, we can see that in **data encryption and transaction data positioning , mining, etc. all play an extremely important role**. As a branch of cryptography, hashing continues to develop and extend. As ordinary novices, if we want to understand some basic concepts of blockchain, understanding this level is enough.