The Ethereum Foundation officially announced in January 2022 that it would eliminate "Ethereum 2.0" and renamed it " Consensus Layer" with the consensus of core developers . This move is to avoid confusion or fraud caused by the name, hoping to create consistency and clarity throughout the ecosystem, and emphasizes that the name change is a unified understanding and will not have any impact on the current development of Ethereum.
Inevitably, some friends will ask, what should we call Ethereum 1.0? According to the complete description of the Ethereum Foundation - in the future, Eth1 will be called the "execution layer" and Eth2 will be called the "consensus layer". The execution layer is where all smart contracts and network rules operate; while the consensus layer uses a consensus mechanism to ensure that all nodes contributing to the network act in accordance with the rules and punish those participating nodes that do not comply with the rules. Right now:
Eth1 → execution layer
Eth2 → Consensus Layer
Execution layer + consensus layer = Ethereum
Where does Ethereum 2.0 come from?
As part of its roadmap, Ethereum has been planning to expand the network in a decentralized manner and transition to PoS (Proof of Stake), aiming to transform the Ethereum blockchain from its current Proof of Work (PoW) consensus mechanism. Proof-of-Stake (PoS) model designed to be faster and more energy-efficient. However, adapting the second largest blockchain from one system to another is an extremely complex multi-step process. It's important to thoroughly evaluate every decision. As early as 2015, The Merge was proposed, and Ethereum 2.0 can also be regarded as the post-merger term.
Why not use Eth 2.0?
The foundation also stated the following reasons for deciding to change its name:
psychological cognition
“A major problem with the Eth2 terminology is that it creates a false mental model for new users of Ethereum. They think that Eth1 is before and Eth2 is after, or that Eth2 and Eth1 no longer exist. But neither of these is true. By removing the Eth2 terminology, we can avoid confusion for future users."
confrontational
"The Ethereum roadmap, Ethereum 2.0 and the ability to clearly express the Ethereum roadmap. Precisely and accurately describe the development roadmap of Ethereum in words so that users can understand and choose Ethereum to the greatest extent."
Prevent fraud
“Bad actors must use Eth2’s action token to upgrade users, telling them to exchange ETH2 tokens for ether. Our updated terminology system makes it clearer about both this scam and making the ecosystem safe.”
Pledge Clarity
"Merchant is also using "representative of the ETH pledged in the beacon to create these two pledge chains." "Users of ETH actually received 2 pledge services," causing potential confusion. "
Why move to PoS?
Compared to PoW (Proof of Work) which requires miners to compete for rewards based on the computing power they can obtain, Proof of Stake (Proof of Stake) has randomly selected validators relative to the total amount and time of their ether (ETH) currency. Pledged. PoS validators do not need to mine blocks to maintain the network. Instead, they need to create new blocks when selected and validate other blocks when not selected. Once a participant has verified the latest block of transactions, other contributors can attest (confirm) that the block is valid. When enough proofs are made, the network adds a new block. The network distributes rewards in Ether, the blockchain’s native currency, in proportion to each validator’s stake.
The reasons for Ethereum to switch to PoS are very obvious from a technical and market perspective. In the latest article published by Ethereum co-founder Vitalik Buterin, he expressed the reasons why Ethereum will switch from the current PoW system to a PoS system - in his It seems that under the same cost conditions, PoS provides better security, which is undoubtedly an important guarantee for the public chain; and the PoS system can recover faster after being attacked. The last advantage is that PoS has better security than ASIC mining. Mines are more decentralized.
Although becoming a validator requires advanced technical knowledge and expertise, anyone can join as long as they meet the minimum requirement of 32 ETH. Those unable to reach the threshold can still contribute and receive a portion of the rewards by staking ether in the pool (which is managed by a third party).
What happens after the merger?
Essentially, the goal of the merger is to speed up the process from PoW to PoS. To speed up the transition, developers are working to reduce features that may cause delays and temporarily disable the ability to withdraw staked ETH after the merge is complete. However, these may be addressed in a post-merge "cleanup" upgrade.
While the merger won’t immediately solve scalability challenges, it will help prepare the Ethereum version of the secondary shard chain for the network, which will rely on a fully functional PoS network to function. By spreading the network's data load across 64 blockchains, sharded chains provide applications and aggregations with an additional and cheaper layer to store data. At the same time, it enables layer 2 systems to provide low transaction fees and benefit from the security of the Ethereum mainnet.
List of other consensus mechanisms
PoW: Proof of Work (Proof of Work)
The representative public chains of PoW are Bitcoin and Ethereum (before the merger). PoW relies on machines to perform mathematical operations (AND or operations to calculate a random number that satisfies the rules) to obtain this accounting right, and sends the data that needs to be recorded to other nodes in the entire network. After verification by other nodes, a consensus is reached. Then store the data. In one sentence: the more you work, the more you gain (only with actual labor can you achieve results)
The advantages of PoW are very obvious. The algorithm is simple and easy to implement; nodes can reach consensus without exchanging additional information (nodes can enter and exit freely); destroying the system requires a huge cost; it requires the participation of all nodes in the entire network and is completely decentralized. .
The disadvantages are the security issues caused by computing power and a large waste of resources. At present, Bitcoin has attracted most of the world's computing power. The new blockchain must find a different hashing algorithm. It is difficult to use the same computing power to get the same security guarantee as in the past. Moreover, the period for reaching consensus is long and is not suitable for commercial applications (it is easy to produce forks, needs to wait for multiple confirmations, and it is difficult to shorten the confirmation time of blocks).
PoS: Proof of Stake (Proof of Stake)
PoS is an upgraded consensus mechanism of PoW. It does not need to consume electricity to perform calculations. According to the difficulty of obtaining the accounting rights of each node, it is inversely proportional to the equity held by the node, which reduces the difficulty of mining in an equal proportion, thereby speeding up the mining process. The speed of finding random numbers . There are validators in PoS. It is still based on hash operation competition to obtain accounting rights, and the fault tolerance is the same as PoW. For example, PoS is analogous to the banknotes in our hands. The more money we have, the more benefits we get in life.
PoS shortens the time to reach consensus to a certain extent and improves transfer efficiency; it no longer requires a large amount of energy and computing power for mining. But its shortcomings are also here, that is, it still requires mining, which essentially does not solve the pain points of commercial applications; all confirmations are only probabilistic expressions, not a deterministic thing, and there may be other attack impacts in theory; When the degree of decentralization weakens, it is easy for the strong to remain strong, and large currency holders hold the currency to earn interest, thus causing monopoly problems.
DPoS: Delegated Proof of Stake (Delegated Proof of Stake)
The representative public chain of DPoS is Polkadot. The main difference from PoS is that the node elects a number of agents. After authorizing the votes to the agent, the agent verifies and keeps accounts. The wallet is the status monitor. Its compliance supervision, performance, resource consumption and fault tolerance are similar to PoS. Similar to board voting, currency holders vote for a certain number of nodes, and the nodes select agents to perform verification and accounting on their behalf. For example, if currency holder A supports the agent with 50 coins, and currency holder B supports the agent with 10 coins, then A's voting weight is 5 times that of B. In one sentence: nodes elect a number of agents, who verify and keep accounts.
The advantage of DPoS is that it can significantly reduce the number of nodes participating in verification and accounting, and can achieve second-level consensus verification; through the approval voting system, it can ensure that even if one person has 50% of the effective voting rights, he cannot choose a block producer alone. , ensuring the security of the algorithm; when most block producers have problems, DPoS can still continue to work. The disadvantage is that the entire consensus mechanism still relies on tokens, and many commercial applications do not require the existence of tokens. There is also weak centralization, and the degree of decentralization is not high.
PBFT: Practical ByzantineFault Tolerance (Practical Byzantine Fault Tolerance Algorithm)
PBFT is a state machine copy replication algorithm that generally includes three protocols: consistency protocol (agreement), checkpoint protocol (checkpoint), and view change protocol (view change). It provides (n-1)/3 fault tolerance while ensuring liveness and safety. In distributed computing, different computers try to reach a consensus through message exchange; but sometimes, the coordination computer (Coordinator/Commander) or member computer (Member/Lieutanent) on the system may exchange wrong messages due to system errors, resulting in Affects the final system consistency [9]. The Byzantine Generals Problem looks for possible solutions based on how many faulty computers there are. Although it is impossible to find an absolute answer, it can only be used to verify whether a mechanism is effective. In one sentence: Each "general" runs a calculation or operation based on a combination of internal state and new information to reach a personal decision. Individuals will share the decision and determine a consensus decision based on all decisions.
The advantage is that the system can operate without the existence of coins. Each node of the PBFT algorithm consensus is composed of business participants or supervisors, and security and stability are guaranteed by business stakeholders; the consensus delay is about 2 to 5 seconds, basically reaching Commercial real-time processing requirements; high consensus efficiency and high throughput, which can meet the needs of high-frequency transaction volume; it does not use the power consumption mode of workload proof, which is more energy-saving and environmentally friendly.
The disadvantage is that it is limited by the number of nodes and nodes require election or permission, so the scalability and decentralization are weak; the fault tolerance is low , and when 1/3 or more of the bookkeepers stop working, the system will not be able to provide services; When 1/3 or more of the bookkeepers jointly commit evil, and all other bookkeepers are divided into two network islands, the malicious bookkeepers can cause the system to fork, but will leave cryptographic evidence.
PoC: Proof of Capacity
A PoC shows that someone has a legitimate interest in a service (such as sending mail) by allocating a certain amount of memory or disk space to solve a challenge provided by the service provider. Although the name of Ateniese et al.'s paper is also "Proof-of-space", it is actually a PoW protocol that uses MHF (Memory Hard Function, a hash algorithm whose computational cost depends on memory). PoC uses a method of caching large amounts of data to save computing time. As an example, fill your hard drive with lottery tickets, generate a random number, and then check who matches the most numbers. If you have the best matching number, you win a prize. To sum it up in one sentence: the larger the storage space, the more you can collect (only with actual labor can you achieve results)
The advantage of PoC is that the proof of capacity is more distributed because everyone has a hard drive. You can even mine from your Android phone’s hard drive; miners don’t need to constantly upgrade their equipment. Old hard drives can store data just like new ones; the hard drive can be wiped out after mining is completed and used for its original purpose. The downside is that widespread evidence of capacity mining could lead to another arms race; proof of capacity is a relatively new technology that has not been rigorously tested and challenged in the real world; there is already malware mining on people's computers. Mine Bitcoin. If proof-of-capacity becomes popular, you might see malware plotting against people's hard drives.
The consensus mechanism part is reproduced from https://anquan.baidu.com/article/1098 . If you want to know more about the consensus mechanism and the algorithm process of its implementation, please refer to the original article.
Other references:
The Merge | ethereum.org
https://ethereum.org/en/upgrades/merge/
Ethereum’s Big Day: What The Merge Means For Investors
https://www.forbes.com/sites/qai/2022/06/10/ethereums-big-day-what-the-merge-means-for-investors/?sh=8b30f2b1be39
What Is Ethereum 2.0? Understanding The Merg
https://www.forbes.com/advisor/investing/cryptocurrency/ethereum-2/