The biggest problem with learning blockchain is that the terms used are too ‘high-end’, obscure and out of touch with reality. Without a particularly deep knowledge background, it is difficult to understand what an article is about, and it is also difficult to understand what a protocol or project is trying to do.
Of course, this may also be intentional. It is easier to deceive/take advantage of others when they don’t understand it---if conspiracy theories are used. 😅😅😅
Back to the point, I have recently learned about the blockchain consensus layer, data availability layer, and execution layer, and I will try to summarize them in plain language that ordinary people can understand.
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In blockchain, the consensus layer, data availability layer, and execution layer are three separate but interrelated parts, each responsible for different functions.
1. Consensus Layer
The consensus layer is the part where all nodes in the blockchain network reach consensus. It determines which transactions are recorded on the blockchain and ensures that all nodes have the same view on these records.
Popular explanation:
Imagine there is a big ledger where everyone records transactions. The consensus layer is like a group of referees who need to unanimously agree on which transactions are valid and then write them to the ledger.
If there are 10 people, each of them can propose a transaction. The task of the consensus layer is to select a proposal and get everyone to agree on that choice.
Example:
The Proof of Work (PoW) used by $BTC is a consensus mechanism. Miners solve complex mathematical problems. Whoever solves it first can propose the next block, and other miners verify the block. If the majority of miners agree, the block is added to the blockchain.
2. Data Availability Layer
The data availability layer ensures that data on the blockchain is accessible and verifiable to everyone, even if the data is compressed or stored in a distributed network, ensuring that the data can be retrieved and verified when needed.
Popular explanation:
Imagine if our big ledger is very large, it is impossible for everyone to keep a complete copy. The data availability layer is like a librarian, ensuring that everyone can borrow and view any page of the ledger when needed, and confirm that the content of the ledger has not been tampered with.
For example, Celestia$TIA Allowing nodes to randomly check a portion of the data in a block to verify the data availability of the entire block without storing the entire block. This is like only looking at a few pages in the ledger to be sure that the entire ledger is complete and valid.
3. Execution Layer
The execution layer is responsible for actually processing transactions and updating the state of the blockchain. It runs smart contracts, executes transaction logic, and updates account balances and other state data.
Popular explanation:
Continuing with the example of the big ledger, the execution layer is like an accountant, responsible for calculating each transaction in detail and updating the data in the ledger, such as who transferred how much money to whom.
If you still feel confused after saying so much, let me explain it with a simple example.
Suppose we have a decentralized Taobao:
Consensus layer: Decides which transactions (such as buy and sell orders) are valid and packages these transactions into blocks. Everyone needs to agree which orders are real before they can be recorded on the blockchain.
Data availability layer: Ensures that all transaction data (such as order details) can be verified and accessed to prevent data loss or tampering.
Execution layer: handles the actual transaction logic (such as buying and selling matching, payment settlement), and updates the status on the market platform (such as inventory and balance).
Through this modular design, different functions of the blockchain are independent, so that each layer can be optimized and expanded independently, providing higher flexibility and scalability.
This way, what I wrote is clear and easy to understand, right?
