Ethereum roadmap: Rollup+sharding is the key to capacity expansion after consolidation

Yesterday, Ethereum finally completed the consensus iteration from POW to POS. The merger is only one link in the Ethereum roadmap. What will the Ethereum roadmap look like? First, the Ethereum roadmap is divided into three stages: beacon chain, merging and sharding.

Their time nodes are

Beacon chain: December 1, 2020

(Rollup: Arbitrum will be launched in September 2021, and the upgraded version Nova of Arbitrum will be launched recently. Optimal will be launched in March 2022. ZK rollup is still in the development stage.)

merge: September 15, 2022

Sharding: The partition scheme in 2023 is called Danksharing, and the primary stage is Proto Danksharing.

About consensus, execution and data availability

When we review the operation mechanism of Ethereum, a world computer, we need to understand three terms: consensus, execution and data availability.

Consensus: The consensus confirms the authenticity of authoritative data stored on the blockchain. Whether POS or POW, participants have reached a consensus on the authenticity of the block.

implement: Execution means that the miner (verifier) obtains the N status, and then fetches the transaction from the memory pool to change this status. This step involves calculation.

Data availability: refers to the data hosted on the blockchain node. These data that need to be permanently reserved on the blockchain need a considerable block space. This makes block space scarce (the maximum block space is 1.85MB).

In the Ethereum roadmap, beacon chain& The merger has made changes in consensus; Rollup and sharding are aimed at cost reduction and efficiency improvement in execution and data availability.

Beacon Chain; merge

Beacon chain exists as a consensus layer (different from the executive layer of the main network), and its role is to coordinate and manage the pledgee network. The Ethereum merger is more like the process of connecting the Ethereum main network to the new engine of beacon chain. The consensus level switch from POW to POS makes the whole system more energy efficient, and also tightens the control of the entire Ethereum network on the verification node (because of the existence of a penalty mechanism).In the future, POW miners will be divided into two roles: Builder and Proposer (this division is also called PBS).Builder is responsible for packaging blocks, while Proposer is responsible for block bidding (without knowing the block content).

After the merger on September 15, the most noteworthy thing isShanghai Upgrade。 Among them, the functions that Ethereum core developers need to developone ofIt is to help the pledgor withdraw the Ethereum stored in the beacon chain (this part is worth 2.1 billion dollars)second, upgrade EVM. In the past two years, EVM has not carried out any upgrade, partly because the inclusion of this upgrade in Merge will increase the difficulty of development.thirdProtoDanksharding is the primary version of Danksharding. The date of Shanghai Upgrade has not been determined yet, and there are differences within Ethereum regarding the functions to be developed for this Shanghai Upgrade. The more complex the function set included in Shanghai, the more complex the upgrade is, and the greater the possibility of upgrade delay.


Due to data availability, consolidation will not bring any changes. That is, Ethereum will not expand, and Layer1 will still have the same experience. At this time, Rollup+partitions have made changes in implementation and data availability, enabling Ethereum expansion. At the execution level, the Rollup calculation is transferred to the off chain processing and execution, while the transaction data remains on the main chain. However, Rollup has not improved the data availability, which means that the gas cost on Rollup is still high due to the main network congestion. To this end,The improvement of sharding in data availability mainly comes from the refined classification of data.The new sharding mode, Danksharing, has laid the keynote of mainly serving Rollup and opened a roll up centric route.

Danksharing is an updated Ethereum sharding proposal after 2020, which eliminates the previous capacity expansion schemes such as status channel and Plasma. Proto Danksharing (the initial stage of Danksharing), Layer1 provides a new data type to Layer2, which leads to the so-calledBlob Data。 Blob data can be understood as insensitive and a large amount of trivial data, which is different from callable transaction data such as Calldata. Blob data is separated from Calldata (callable transaction data). EVM does not need to access blob for execution. EVM only needs to view its commitment to blob. Because some files compressed on Rollup can be directly decompressed into readable mode or downloaded to the chain without EVM access. As a result, Blob data processing costs less than callable transaction data Calldata. In addition, Blobdata stored in the consensus layer will be deleted one month later to reduce the pressure on the block space size. Proto Danksharing refines data processing by subdividing data types, thus greatly reducing the system workload.

Proto Danksharing did it by the wayGas Cost Economic ModelImprovement (here calledEIP4484); That is, different charging models are used to process blob data and calldata. For example, when you are doing some operations on the second floor, you happen to catch up with a popular NFT in sales. The gas fees you need to pay will not be affected by the hot NFT sales. However, Proto Danksharing also brings many challenges, that is, the calculation model of gas cost is more complex. Then Builder (block packager) encounters a problem when seeking the optimal bidder, that is, it cannot identify at once but needs mathematical formula calculation to find the optimal bidder. The reason for this problem is that Calldata and Blob both need to charge gas and cannot touch the gas limit specified in EIP1559. This further improves the requirements for the professional Builder& nbsp;

Proto Danksharing is an important step towards Full Sharding. Once Proto Danksharing is launched, the client executive layer, Rollup developers and users can do it once and for all; Because in the future, Full Sharding will mainly occur in the consensus layer. It can be said that Proto Danksharing has laid a solid foundation for Full Sharding at the logical level.

From the Ethereum roadmap, we can find these rules:

1. Beacon chain+merger is the adjustment of Ethereum consensus+implementation.These two steps separated the architecture of beacon chain (consensus layer) and main chain (execution layer), and the miners' work was redistributed by PBS. Block producers tend to be professional (there are also strict requirements for machines and bandwidth), while block proponents restrict block producers to achieve a balance.

2. Merging is just the prelude to Ethereum's roadmap. Fragmentation+Rollup is the main chapter of Ethereum's becoming a world computer.It is divided into sections to serve Rollup, which carries more narratives of Ethereum. In particular, the sharded Danksharing has adjusted the data availability, involving the sorting of data and the gradient processing of gas costs.

3. Like Cosmos and Poka, Ethereum has also taken the path of modularization.The beacon chain has become the place of consensus/belief (and also plays the role of the treasury), while the main chain is similar to the real-time bulletin board (verification of Rollup and real-time update of block processing), while Rollup is a constantly running machine above (bearing all Dapp functions).

4. As far as the nearest Shanghai Upgrade is concerned, it is an important step to link consolidation and sharding。 However, the core development team of Ethereum has not reached a consensus on which functions to develop. The date of Shanghai Upgrade has not been determined yet.