Files saved by blockchain

1. const SHA256 = require(crypto-js/SHA256);< br />class Block{
constructor(index,timestamp,data,previousHash='&# 39;)< br />{
this.index=index;< br />this.timestamp=timestamp;< br />this.data=data;< br />this.previousHash=previousHash;< br />$this.hash=this.calculateHash();< br />}

calculateHash(){
return SHA256(this,index+this.previousHash+this.timestamp+JSON.stringify(this.data)).tostring();< br />}
}
class blockchain{
constructor(){
this.chain=[this.createGenesisBlock()];<
}
/ / create a generated information block
creategenesis block() {
return new block (0, & quot; 01/01/2019",& quot; Genesis block", 0);
/ / the date is the user's data. In fact, it is the hash value obtained by adding several values together. Here, the information is encrypted and the picture is encrypted. Then the data is still stored in the database, but all the data are hash values. To get this data, you must know the hash value of the previous data block. Then, if the hacker needs to crack all the nodes, the hash value is decrypted, Then all the blocks from the first node to the last node can be decrypted to get the real data. So the security of data stored in the blockchain depends on whether the data is encrypted. If the plaintext is not encrypted, then it is not a blockchain
}
/ / get the last block
getlatesblock() {
return this.chain [this.chain. Length-1]
}
/ / create block
addblock (newblock) {
newblock. Previoushash = this. Getlatesblock(). Hash< br />newBlock.hash=newBlock.calculateHash();< br />this.chain.push(newBlock);< br />}
}

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

generally, the blockchain platform will provide corresponding interfaces, such as RPC, json-rpc, HTTP, etc. of course, the platforms are not the same, and the degree of friendliness is different

some companies specializing in API, such as blockcypher, can provide friendly calling interfaces, and it is not very convenient to write answers on the mobile phone, Search below

as for the storage content, add a point: in addition to the conventional cloud storage, file entities on the file hash record chain also have blockchain based storage schemes, such as IPFs, storej and so on

3.

With the rapid development of Internet technology, it has brought us infinite wonderful and convenient life. At the same time, with the continuous improvement of 5g network, container cloud and high-performance storage hardware, data growth has entered an unprecedented stage of development

AR, VR, Internet of things, edge computers and other devices available everywhere generate a continuous stream of data, just like an open water pipe, the data source has been flowing out. The data generated will increase geometrically. At this time, the storage technology of blockchain will be demonstrated. A few years ago, there was an excellent IPFs project in the blockchain storage technology

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yottachain takes the blockchain as the underlying technology and develops a powerful incentive scheme for miners. With 1GB
of space invested by miners, yottachain can generate 5-10gb of storage capacity, which proces the miracle effect that the purchasing power of digital currency obtained by resource suppliers exceeds the resources they supply

There is no doubt that data storage is now in the initial stage of the transformation from centralized storage to distributed storage. When more and more indivials and organizations begin to use blockchain technology to change all aspects of our lives, I believe yottachain will also make greater contributions to our economy in the new era

4. mining often mentioned in the field of blockchain is actually proof of work (POW)< Br > the so-called workload proof is used to confirm that you have done a certain amount of work. The whole process of monitoring work is usually extremely inefficient, and it is a very efficient way to prove that the corresponding workload has been completed through the certification of the work results< Mining is a process of processing transactions by consuming computing resources, ensuring network security and keeping everyone's information synchronized in the network< This process is called "mining" because it is similar to gold panning, because it is also a new temporary mechanism< However, unlike gold panning, mining provides rewards for services that ensure the safe operation of payment networks. What is the principle of mining< Br > anyone can become a miner by running software on specialized hardware< Br > the mining software monitors the transaction broadcast through the network and performs appropriate tasks to process and confirm these transactions< Br > miners can earn transaction fees paid by users to speed up transaction processing and issue new coins according to fixed formula after completing these tasks. New transactions need to be included in a block with mathematical workload proof to be confirmed< This kind of proof is difficult to generate because it can only be generated by trying billions of calculations per second< Br > miners need to run these calculations before their blocks are accepted and rewarded. As more people start mining, the difficulty of finding effective blocks will be automatically increased by the network to ensure that the average time to find a block remains at 10 minutes< Br > therefore, the competition for mining is very fierce, and no indivial miner can control the content contained in the block chain.

5. It can be
e-dinar internal market allows P2P transactions without commission and foreign exchange restrictions, and digital gold currency e-dinar supports any means of payment in the market< br /> http://pinpai.szonline.net/pp0615/20160615/567354.html?__ r=138