区块链数据到底存在哪些问题,区块链数据到底存在哪些风险

近年来，随着区块链技术的发展，越来越多的企业开始使用区块链技术，以解决存储和传输数据的问题。但是，区块链数据也存在一些问题和风险，它们必须得到解决才能更好地发挥区块链技术的优势。

首先，区块链数据存储的问题是一个棘手的问题。由于区块链数据是分布式的，所以存储起来比较复杂，需要大量的硬件资源和软件资源，这会导致成本增加。此外，存储区块链数据还可能会遇到一些安全问题，比如数据泄漏、篡改等，这也是一个需要重视的问题。

其次，区块链数据传输的问题也是一个比较复杂的问题。由于区块链数据是分布式的，所以传输起来比较复杂，需要大量的网络资源和计算资源，这也会导致成本增加。此外，传输区块链数据还可能会遇到一些安全问题，比如数据丢失、篡改等，这也是一个需要重视的问题。

此外，区块链数据到底存在哪些风险也是一个需要重视的问题。首先，由于区块链技术是新兴技术，目前还没有完善的安全措施，这就使得它容易受到黑客的攻击，从而导致数据泄漏或篡改。其次，区块链技术的应用还受到政策限制，比如有些国家的法律法规不允许使用区块链技术，这也是一个需要考虑的风险。

总之，区块链数据存在一些问题和风险，必须得到有效解决，才能充分发挥区块链技术的优势。因此，企业在使用区块链技术时，应该仔细研究区块链技术的可行性，并采取有效的措施来确保数据的安全性和可靠性。只有这样，才能充分发挥区块链技术的优势，为企业带来更多的收益。

❶ Blockchain: Returning the ownership of data to individuals

This article explains through examples how blockchain technology can return ownership of personal information to individuals.

First, let’s look at Taobao’s data ownership. Taobao's data includes personal browsing product traces, personal purchase product details, merchant sales data, product logistics data, payment and collection data, etc. All personal and merchant data are on Taobao's servers. Who does this data belong to? Taobao users (including customers and merchants) believe that data is generated by users and should belong to them. Taobao believes that the server hardware facilities that record user data belong to Taobao, and the data also belongs to Taobao.

This is like planting a tree in someone else’s yard. It’s true that you planted this tree, but this tree was planted on someone else’s land. This tree The survival of the tree cannot be separated from your sowing, nor can it be separated from other people's land. So whose tree does it belong to?

Fortunately, due to the introduction of laws related to the protection of personal information, Taobao's data ownership belongs to users. Unfortunately, there is no way for users to exercise ownership rights. Because you cannot transfer or delete your data from Taobao's servers unless you pay the corresponding cost. Continuing with the above example of planting a tree in someone else's yard, if you want to realize the ownership of the tree and dig it away, that won't work because, first, others won't let you enter the yard; second, you don't have the land yourself, so dig it away. This tree, the tree is dead.

Therefore, having ownership of data does not necessarily mean free disposal of data. Ownership without the right to dispose is in vain. The root cause of this problem lies in the centralized business model and system architecture. In a centralized model, the owner of data ownership has no way to realize the right to dispose of data. Taobao can admit that data ownership belongs to users, but it does not matter. This does not prevent Taobao from using user data to conduct unreasonable operations such as user discrimination, platform selection, traffic monopoly, and bidding ranking. Going back to the above example of planting a tree in someone else's yard, the tree is yours, but others enjoy the shade under the tree and the fruits it produces are enjoyed by others.

Based on the above analysis, only a decentralized model can effectively solve the problem of separation of data ownership and disposal rights, and currently the best decentralized technology is the blockchain.

Blockchain solutions:

Build an e-commerce platform based on blockchain technology. We name this platform "E-commerce Alliance Chain", hereinafter referred to as " Alliance Chain".

Each merchant is connected to the alliance chain as a node, and each customer is connected to the alliance chain as a node. The product information sold by merchants is published on the alliance chain as shared data, and all connected customer nodes can see and browse this information. When a customer decides to purchase a product, the purchase information packageProducts, models, addresses, etc. are passed to merchants through the alliance chain. In this process, each merchant records the transaction information of the customers who transact with it. For transaction information that has nothing to do with itself (other merchants and customers), only the characteristic value (hash value) of the information is recorded; Each customer also records his own transaction information, and only records characteristic values ​​for information that has nothing to do with him.

The purpose of a node recording transaction characteristic values ​​that have nothing to do with itself is to prevent the transaction information on the alliance chain from being tampered with. When one or both parties to a transaction tamper with the transaction information, the characteristic value of the transaction will change. Then, as long as it is compared with the characteristic value recorded by nodes unrelated to the transaction, the tampering will be discovered by the alliance chain.

On the e-commerce alliance chain, there is no centralized node. All nodes are equal. Each node only records its own relevant transaction data. There is no way to save transactions of non-related nodes. data. Using the example of tree planting, each family plants trees in their own yards and cannot let others plant trees in their own yards. Nodes can decide how they want to process their own data. They only need to reach a data processing consensus with the node on the other side of the transaction.

In this way, the e-commerce alliance chain based on blockchain technology truly realizes the unification of data ownership and disposal rights, which is real ownership.

At this point, some people may say that useful services such as customized recommendations and product rankings for some product information are still needed. If the data is scattered in the hands of the owners, then this cannot be achieved. A useful data feature. It doesn't matter, you just need a third-party organization specialized in data analysis to connect to the alliance chain. Merchant nodes and customer nodes are responsible for authorizing the use rights of their own data to third-party data analysis nodes, and agreeing on the specifications for data use through the smart contract technology of the blockchain. The data analysis institutions analyze transactions within the scope of authorization of the use rights. data and provide data services required by other nodes.

In the digital age, data is an important means of production, so it is critical to clearly define the ownership of data. The centralized model will deprive the majority of data producers of their means of production and turn them into essentially proletarians. This is unreasonable. Through blockchain technology, data ownership can be returned to data producers, making production relations in the digital era more reasonable. This is the way forward.

❷ How to store blockchain transaction information

Blockchain is a large distributed ledger. Detailed data must be stored on the longest chain through hashing. To verify the data, only the data verified by most nodes can be saved on the longest chain. The latest data can be synchronized between nodes, while achieving distributed storage of data, which is not easy to tamper with. Each transaction corresponds to a timestamp, and the status of each transaction can be queried based on the timestamp, which is traceability.

❸ Which part of the blockchain is the transaction data written to

The actual blockchain directly stores the content data (such as transaction data) in the database, called a Merkle tree, and then Store the sum of the Merkle tree in the block header.
_Merkle trees have very unique properties that allow us to perform efficient data validation in peer-to-peer networks. A Merkle tree is a binary tree in which nodes store hashes instead of sorted blocks of data. https://right.bdstatic.com/vcg/edit/.jpg
Blockchain is a chain composed of blocks one after another. Each block stores a certain amount of information, and they are connected into a chain in the order in which they were generated. This chain is saved in all servers. As long as one server in the entire system can work, the entire blockchain is safe.
These servers are called nodes in the blockchain system, and they provide storage space and computing power support for the entire blockchain system.

❹ Does the data on the blockchain exist in the contract?

The data on the blockchain exists in the contract. According to the query of relevant public information, in the blockchain, data is in a state of continuous growth. Once the data is stored on the chain, it will exist permanently. If you need to save data, you can call a smart contract to encrypt the data and put it on the chain. After the data is put on the chain, it cannot be deleted. There will be a modification history after modification, and the changes in the data will be retained on the blockchain.

❺ Where does the data exist? Whether each node must have a large enough storage medium

The blockchain uses a distributed storage method. The data of the blockchain is composed of blocks. Chain nodes are used and stored, and multiple nodes are linked through the network to ultimately form a complete blockchain network.

Regarding the size of the node, taking Bitcoin network nodes as an example, there are full nodes, pruning nodes, and SPV lightweight nodes. This classification The method is based on two differences: first, whether this node has downloaded the latest and most complete Bitcoin blockchain; second, whether the node can independently verify Bitcoin transfer transactions, that is, whether it can independently realize the basic functions of a node.

Full nodes download the latest complete blockchain data and are the backbone of the Bitcoin network. There are two main types of people using such nodes, one is independent mining miners, and the other is users who run Bitcoin software (Bitcoin core) using default settings.

The pruning node can also independently complete the confirmation of Bitcoin transfers, but it does not download the entire blockchain to the local.

Lightweight nodes are generally used on mobile computing devices. Due to capacity limitations and high requirements for portability, people usually do not download the blockchain locally. Therefore, the wallet'sThe operator will check and confirm the transfer in each user's wallet with the complete blockchain on the Internet through the SPV (Simple payment verification) protocol.

In the Ethereum network, there are similar classifications of full nodes, light nodes, and archive nodes, so not every node requires huge storage space and must be selected based on the node function.