There are many authors who write blockchain knowledge and science popularization, but I still hope that What I write is the most accessible.
20:20, be there or be square
Definition 1.
A blockchain is essentially a decentralized, distributed database in which blocks of data generated by cryptography are connected in series to form a chain of blocks. Each block contains transaction information of the entire network over a period of time, which is used to verify the validity of its information (anti-counterfeiting) and generate the next block.
Therefore, blockchain is a technical solution that allows participants to jointly maintain a database in a decentralized and trustless way.
In layman’s terms, blockchain is universal bookkeeping, not controlled by any centralized individual or institution.
Traditional database:
Traditional databases are stored in the central server, for example, the huge data behind Taobao must be stored in alibaba’s server, controlled by Ali. This can be understood as a huge ledger, which needs to be updated and maintained by Alibaba every time there is a transaction. As alipay users, it is impossible for us to participate in bookkeeping and transaction verification.
This is the typical centralized database management mode, which has been running for so many years and is used and recognized by hundreds of millions of users.
The drawbacks and defects of centralized bookkeeping are mainly the trust problems and cross-regional consensus problems of centralized institutions. The last article has been explained. If you haven’t seen it, you can turn back and look ~
Distributed database:
Blockchain completely overturns this approach. It calls for collective bookkeeping, where the validity of transactions is verified by the participants in the system, without the need for a centralized organization, and data is distributed on each node.
In the Bitcoin system, each partner has the same ledger, which consists of many pages of bills that record data from the first transaction to the latest transaction in the system. The transaction data is open and transparent, and everyone can verify that each transaction is valid.
Every 10 minutes in the system will generate a page of the new bill, for the right to charge to an account of a friend can charge to an account on the new page, records of all transactions, the 10 minutes on can get new bills BTC 12.5 reward these transactions, and all the poundage reward (block reward halved once every four years, from 2009 the first 50 BTC, It has now halved twice). The way to compete for the right to account, is to let all partners every 10 minutes at the same time to find a random number, the fastest to find this random number of partners have the right to account. After billing, send the new bill to the network for all the other friends to verify. The other friends verify that this page of bills is ok, put in their own books.
Thus, each node in the system has an identical ledger, and each page of the ledger is a data block.
And blockchain systems use powerful cryptography to protect data from undetected tampering, making transactions secure and efficient.
2. The security
Intuitively, this way of accounting is obviously much more complex than centralized accounting, there will be highly redundant data, and waste a lot of storage and bandwidth resources.
But blockchain builds extremely high security precisely in this highly redundant and costly way.
The cost of doing evil in centralized systems:
Imagine that in a centralized system, the evil cost of the centralized organization is only the consumption of people’s trust, and the relative benefits of other costs are almost negligible.
The cost of evil in decentralized systems:
In a blockchain system, the rights of each node are the same, and the destruction of one or a few nodes will not affect the security of the entire system, nor will it cause data tampering or loss.
In addition, the ledger of each node in the system is the same, so it makes no sense to tamper with the data of a single node. The system only follows the data that most people agree with, and the data that a few people tamper with is discarded by the system.
> Node attack:
In a decentralized blockchain system, the way to do evil is to control most of the nodes.
Take Alipay as another example. If Alipay is a decentralized payment system, the only way for some criminals to modify payment data for their own profit is to control most of the hundreds of millions of users of Alipay. Such evil costs can be imagined to be huge.
So when the number of nodes in a system reaches an order of magnitude higher, tampering with data becomes much less likely or even impossible.
Word-wrap: break-word! Important; “>
Of course, you can also use the majority of the network’s computing power to launch a 51% attack. In fact, bitcoin’s computing power is basically in the hands of several large mining pools. If these large mining pools do some cooperation, they can launch a 51% attack. But imagine that the cost of their attack is countless too expensive mining machines and consumption of a large number of power resources, manpower, site and so on, the cost is unimaginable. Once the attack is launched, the trust system of the whole network collapses, the price of Bitcoin plummets, so the attackers are left with a pile of scrap iron, completely unprofitable. Why kill a thousand enemies and lose eight hundred?
I don’t think anyone would try this when the benefits of knowing the cost of an attack are far greater than the benefits of being an honest node.
Therefore, the birth of blockchain is a challenge to centralization. Its vision is to create a completely decentralized world in which everyone has equal rights. It is the first time in human history that technology has been used to guarantee the sanctity of private property.
However, at present, blockchain technology is not mature enough. It is just like a super power baby with infinite potential. It is strong but also fragile.
Either way, this baby has been born and is growing rapidly, and whether you accept it or not it’s there, like it or hate it, doesn’t affect its future development.
Instead of being closed and unwilling to accept new things and spending a lot of time watching TV series, staying up late and surfing weibo, it is better to spend a little time every day to read Fanfan’s articles and learn something, don’t you think
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