Odd technical guidelines

There is no doubt that blockchain is one of the hottest concepts recently. Blockchain, bitcoin, Ethereum and ICO are all popular in wechat moments, but do you really understand the meaning of these terms?

Block chain

From a technical point of view, blockchain is a technical system that is jointly maintained by many parties, stores data in a block chain structure, uses cryptography to ensure the security of transmission and access, and can realize the consistent storage of data, which cannot be tampered with and cannot be denied.

For example:

Blockchain is like a train, each train car is stacked with goods, like each block is stacked with data, like all the train cars are connected into a train, like all the blocks are connected into a chain. However, due to the exquisite and special design of the blockchain, the content of the later generated block is affected by all the previous blocks, which leads to the slight tampering of the previous block can be detected, which contributes to the tamper-proof and reliable characteristics of the blockchain.

What is in the compartment (block)?

  • Head: Records the eigenvalues of the current block

    • To generate the time

    • Hash of the actual data (i.e. block body)

    • Hash of the previous block

    • The random number

  • Body: Actual data

    • Trading data

Each new block in the blockchain depends on the hash of the previous block’s content, which in turn contains the hash of its previous block, so each block is tightly linked and cannot be tampered with. This closely linked mechanism is more difficult to understand, can be analogous to the idiom solilong, smooth sailing – smooth sailing – natural.

Knowledge:

Hash function: hash check is often used in forums, software release, is to ensure the correctness of the file, prevent some people from stealing procedures, add some Trojan or tamper with copyright, a set of verification system designed. Each file can be computed with a fixed MD5 code using the Hash MD5 validator.

Asymmetric encryption: Asymmetric encryption algorithms require two keys, a public key and a private key. If the public key is used to encrypt data, only the corresponding private key can be used to decrypt data.

The currency

The founder, Satoshi Nakamoto, is presumed to be Japanese. Bitcoin is the first peer-to-peer electronic currency system using blockchain technology. The Bitcoin system uses blockchain technology to maintain a distributed ledger of bitcoin transactions.

Mining:

Anyone can become a Bitcoin miner by running software on dedicated hardware. Mining software listens for broadcast transactions over P2P networks and performs the appropriate tasks to process and confirm those transactions. In doing so, bitcoin miners earn transaction fees paid by users to speed up transaction processing and a fixed formula for issuing additional bitcoins.

New transactions need to be included in a block with a mathematical proof of work to be confirmed. This proof is difficult to generate because it can only be generated by trying billions of calculations per second. Miners need to run these calculations before their blocks are accepted and rewarded. As more people start mining, the difficulty of finding effective blocks is automatically increased by the network to ensure that the average time to find blocks is kept at 10 minutes.

The specific process of the transaction:

Suppose A transfers 10 bitcoins to B, the simplified version of the procedure is as follows:

  1. Confirm the information of both parties of the transaction, including A’s wallet address and wallet balance, and B’s wallet address.

  2. Initiate a transaction application through the Bitcoin client. Each transaction application will generate a public key through the private key, and everyone can verify whether the transaction is legitimate through the public key.

  3. The miners have bundled all trades made in the past 10 minutes into a new trading block.

  4. The miner’s computer starts calculating an encrypted hash function. A new hash value is calculated based on the hash value of the previous block, the new transaction block, and the random number.

  5. The Bitcoin system requires new hashes to have a specific format — they must start with a specific number of zeros. Miners cannot predict which random number will produce a hash starting with the required number of zeros, so they are forced to create many hashes with different random numbers until they get the one that works.

  6. The timestamp server timestamps the hash result of a block of data and publishes the hash result widely.

  7. Each block contains an initial transaction called Coinbase, which is a payment of 50 bitcoins to the winning miner.

  8. Finally, new blocks are added to the blockchain.

Bitcoin coins are issued by mining (proof of work), the total number is programmed to 21 million, and the first block reward is hard-coded to death. The reward a miner gets for digging a block will be cut in half every 210,000 blocks, or roughly every four years at an average of 10 minutes for digging a block.

Since January 2009, the reward has been 50 bitcoins per block, halved to 25 bitcoins per block in November 2012, and halved to 12.5 bitcoins in July 2016. According to this rule, by the year 2140, all bitcoins (20,999,999,980) will have been issued and no new bitcoins will be created after that.

Problem thinking:

  1. Is mining a waste of resources?

  2. Are there any blockages in bitcoin trading?

  3. Where does blockchain data live?

  4. How does the system continue to work once bitcoin is issued?

The etheric fang

Founder Vitalik, Russian.

When he was 19, he published his first Ethereum White Paper. He affirmed the great idea of a “distributed database” for the Bitcoin network, but also pointed out its disadvantages: it was not scalable enough, and only bitcoin was a symbol. Ethereum, on the other hand, can be viewed as a distributed computer where anyone can upload and execute applications, and miners are like computing cpus that make up a decentralized world computer.

One of the biggest differences between Ethereum and Bitcoin is that it provides a more powerful contract programming environment. If Bitcoin functions only as a digital currency, ethereum allows users to write smart contract applications, bringing blockchain technology directly into the 2.0 era.

Take a look at the structure of Ethereum:

For example:

From a platform perspective, Ethereum is similar to Apple’s App Store; From a technical point of view, Ethereum is similar to a blockchain operating system.

Smart Contracts:

A smart contract is a computer program that directly controls a digital asset. Smart contracts in Ethereum run on Virtual machines, commonly known as EVM (Ethereum Virtual Machine). This is a sandbox for smart contracts, which are stored on Ethereum’s blockchain and compiled into Ethereum virtual machine bytecode to run smart contracts through the virtual machine. Because of this middle layer, Ethereum also implements contract code compilation in multiple languages, with each Ethereum node in the network running the EVM implementation and executing the same instructions. If Bitcoin is a two-dimensional world, ethereum is a three-dimensional world, and there are countless different two-dimensional worlds that can be realized. (the etheric fang source is maintenance on the lot: https://github.com/ethereum).

In other words:

You can build any app using Ethereum’s smart contracts, including using Ethereum to develop virtual coins.

At the same time, in order to prevent computational waste, each transaction needs to set a limit to limit its total calculation step, which is to make the transaction execution cost, each transaction has to pay a certain handling fee (Gas).

ICO

If they want to sell digital tokens, they want to sell them to private investors. In an ICO, investors use existing virtual digital currencies, such as Bitcoin, in exchange for new tokens issued by ICO programs. Because of the small number of owners and the high volatility of the new currency, the sale price on the exchange is likely to be much higher than the issue price. The sponsors of ICO programs use the traditional digital money they have borrowed to exchange it for legal tender such as RMB on exchanges and then invest it in designated technology projects.

Blockchain technology implements a third-party notarization mechanism to ensure that once you participate in crowdfunding and pay, you will get the corresponding digital cryptocurrency. This partially solves the problem of trust in ICOs and lowers the threshold for PARTICIPATION in ICOs.

Special note: On September 4, 2017, the People’s Bank of China and other 7 ministries and commissions jointly issued a document, the first official characterization of ICOs, saying that “token issuance financing… Is essentially an unauthorized public fundraising activity “, and demanded that “all types of token offering fundraising activities should cease immediately”.

Cut chives

“I can calculate the trajectories of heavenly bodies, but I have difficulty in calculating the madness of man.” Newton –

While others rush to dig for gold, I make shovels:

According to the conversion, a bitcoin machine of 15,000 yuan (the latest version OF S9) can bring about 0.0011 bitcoins a day. The current market price of Bitcoins is 9,000 DOLLARS, which is about 60 yuan a day.

Bitmain earned nearly $360 million in 2017 on revenue of $2.5 billion.

You can issue money by bragging:

With ethereum’s services, it’s so easy to create a virtual coin. You can search the Internet for tutorials, and a similar programmer can create a new coin. If you’re too lazy, there’s taobao:

The exchange has the deepest water:

Sylvain Ribes, a foreign virtual currency researcher, published an article in which he pointed out that most virtual currency exchanges do their own trading, with the most fake exchanges generating as much as 93% of their trading. Huobi’s trading volume fraud is around 60%. Want to land the exchange circle money, you have to hand in to the exchange “on the currency fee”, or cash, or the share of a part of the currency offset to the exchange, after landing the exchange himself cash.

Problem thinking:

There are already many Internet companies in China involved in the blockchain field. What is the relationship between these products such as Xunlei PlayerCloud, 360 Sharing Cloud, Baidu Letz Dog and NetEase Planet and blockchain?

World of you when not

Just your shoulder

There is no


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