原文标题：《 模块化区块链:推动 Web3 生态进化的基础设施 》
Original article by Ray, ArkStream Capital
There's no doubt that modular blockchains will be the new infrastructure narrative for the next cycle, but that doesn't mean that single blockchains will be replaced. On the contrary, the development of modular blockchain will become an important impetus to promote the evolution and progress of monomer blockchain. Both will lead and support the next one with complementary advantages. 10 Web3 ecology with hundreds of millions of users;
Compared to the precise definition of modular blockchain, the implementation layer, data availability layer, consensus layer and settlement layer of modular blockchain can be felt and understood through the transaction and block data.
The executive layer acts as the practice pioneer of single blockchain transaction expansion and computing outsourcing. The data availability layer not only reduces the cost and improves the efficiency of blockchain data storage, but also ensures the availability after data verification under the consensus layer. The consensus layer is dedicated to reusing the power of decentralization to create a new decentralized construction framework. The core of settlement layer is to optimize and improve the matching of account assets and transaction flow, so as to achieve the correct correlation between the two.
The birth of Bitcoin marks the arrival of a decentralized electronic cash system, through which people recognize the concept of blockchain technology and the consensus mechanism of proof of work. Then came Ethereum, a worldwide computer and smart contract platform whose powerful programmability showed great promise in finance, social and gaming. Despite more than a decade of development, blockchain is in its infancy in terms of popularity and technology precipitation, but there is no doubt that its potential is still huge.
In general, the public chains we are dealing with now can be collectively referred to as monomer blockchain. They take each transaction as a carrier, store legal and valid transaction records through blocks, and implement decentralized, trust-free, tamper-proof distributed ledger networks through specific consensus mechanisms.
The characteristics of a single blockchain are that it can establish a complete ecosystem from wallet, application, middleware to infrastructure in an all-round and independent way, and maintain a close relationship between all parties. However, with the development and prosperity of the ecosystem, there will be problems such as transaction blocking, transaction cost rising, network participation threshold too high, and the cost of maintaining the whole network state increasing. When high concurrent usage is encountered, single blockchains often become expensive and difficult to use due to transaction throughput limitations, and the user experience is greatly affected. In addition, as blockchains continue to grow, the entire network will experience a state explosion, and the barriers to maintaining the network will not only increase, but also increase the cost.
In order to solve the problems existing in single blockchain, industry insiders have conducted extensive research and exploration in capacity expansion, state pruning and other aspects over the years, including but not limited to state channel, side chain, Rollup, light node, sharding, modularization and other technologies. The research and development of these technologies continuously optimize the technology stack of blockchain, and improve the popularity of blockchain technology.
In essence, modular blockchain redefines and divides the layered architecture of the blockchain into different modules through the idea of aggregation and composition. These modules are independent of each other, can be modified and extended as required, and can be combined with each other. This combination of modular blockchain can not only improve all aspects of performance, but also meet a variety of application scenarios.
In the past, when thinking about the architecture of a single blockchain, we used to split the results into: an application layer carrying decentralized applications, an execution layer responsible for implementing the intelligent contract logic of decentralized applications, a consensus layer dealing with transaction validity, transaction order and block composition, a data layer maintaining and storing transactions and blocks, and a network layer for point-to-point broadcast communication.
The hierarchical understanding of modular blockchain is easily based on the preconceived thinking of monomer blockchain, which will cause a lot of confusion. At this point, you can view Ethereum from the user's point of view as it is running. Rollup Intuitive and in-depth understanding of the layer 2 network Arbitrum. By Arbitrum The White paper on the layer 2 network transaction flow: It can be known that transactions submitted by users no longer interact directly with the first-layer network, but are collected and processed in batches by the sequencer of the second-layer network. The sequencer compressors and sends the original data of multiple transactions processed in batches to the first-layer network. At the same time, it also sorts the transactions processed in batches to calculate the changes in user and network status. The status results are then sent to a layer of network for settlement.
The sequencer of the layer 2 network collects and batch processes transactions (execution layer)
Layer 2 network compression processes transactions and then sends them to Layer 1 network (data availability layer)
As for the settlement of transactions. Arbitrum Block browser does not do a very good one - to - one couplet, here we directly pass. Arbitrum Official website deployment in Ethereum smart contract start, analysis Delayed Inbox The contract involves the function related to settlement: send L1 FundedContractTransaction, when clearing divided call; Called when there is no discrepancy in settlement. Outbox Contractual. updateSendRoot. Relevant contracts address, please refer to: https://developer.arbitrum.io/useful-addresses.
We now have a clear and intuitive understanding of the functions and roles of the execution layer, the data availability layer, the consensus layer, and the settlement layer. The execution layer is the sequencer's batch processing of the transaction, including the original transaction data compression and state transition calculation. The settlement level is responsible for confirming the finality of state changes. The data availability layer is a layer of network storage and maintenance of compressed transaction data collected by the execution layer. As for the consensus layer, it guarantees the security that the execution layer depends on in terms of the data availability layer and the settlement layer.
As defined from the top down, the modular blockchain hierarchy is shown below:
Since the settlement layer involves the transaction validity proof design of different execution layers, such as optimistic fraud proof and zero-knowledge proof, we will not make further understanding for now. Below, we will directly understand the implementation layer, data availability layer and consensus layer of modular blockchain, focusing on the background of their development, the problems they solve, as well as their current development and challenges.
There's a term we hear a lot about before we actually come up with an executive product: Ethereum killer. This represents a clear mismatch between blockchain users' performance requirements in terms of transaction throughput, transaction speed, and transaction costs, and what Ethereum offers. For this reason, many new public chains try to explore and study the transaction structure, block design, consensus mechanism and network broadcasting mechanism of the single blockchain itself, so as to construct a new high-performance public chain to achieve massive transaction throughput, fast transaction speed and cheap transaction cost. At the same time, the Ethereum ecosystem is exploring a wide variety of technology and product solutions. To this day, to Rollup Is the main scheme Layer 2 The line dominates, wherein fraud proves optimistic. Rollup Optimism Arbitrum Outpacing others in terms of build, engagement, and retention. EVM Compatible with new public chains, in addition, zero-knowledge proof based ZKRollup (Starknet, Hermez, zkSync, Scroll, Taiko Etc.), based on parallel transaction Fuel, AltLayer, Smooth Etc are also moving forward in their respective programme areas.
With Rollup Iso Layer 2 Eg. These are generally referred to as the vigorous development of Rollup And the executive level concept of parallel trading products was formally introduced. Of course, it's not just Ethereum, it's also optimized. TPS And transaction costs of Solana, BNB Chain, Cosmos, Aptos and other public chains, their respective authorities or communities have proposed their own. Rollup And executive level products. Thus, we not only enter the era of multi-chain co-existence, but also enter the scene of multi-class executive level co-existence. This also brings different problems for developers, users and the ecosystem: the products of the respective execution layer are independent and closed, the ecosystem is difficult to share, users operate between each other in heavy costs, and developers build and operate time cycles and costs are expensive. To this end, to nbsp; Rollup Products as services are also available. For example, Sovereigen Labs, Stackr Labs, Eclipse Builders, Dymension Etc. These products are analogous to the executive level. Hub, which locates in the Layer 2 network Rollup Change to Layer 3 From this, mono-nbSp is constructed. Hub Many Rollup The branch type execution layer.
Due to the historical demand of the expansion scenario, the implementation layer has been exploring and developing products for many years, and their respective schemes have made major breakthroughs in so many years. In the coming cycle, there are still many unsolved problems that are being explored in the products of the executive level: decentralized sequencer, zkEVM And parallel trading.
With the advent of the age of big data and the age of cloud, data, as a basic resource in modern society, can provide help and support in various decision-making scenarios, and its strategic position is just like that of oil in the past. When we talk about blockchain data, we usually mean the various transaction data and smart contract data stored on the chain. These data stores are different from traditional databases. In a sense, blockchain data is distributed, meaning each node stores a complete copy of the data. At present, with the active transaction data of users on the chain and the prosperity of smart contracts, blockchain data shows signs of exponential growth on the basis of linear growth. Bitcoin network from 2016 Year 55 G The size of the whole network has been in accordance with each year. 50 G Growth, but in. 2020 The annual growth of its network size jumps to   from the beginning of 2005. 60 Eg. As of now. 2023 Year 2 Month, the data size of the whole network is 459 G.
As the world's computer and smart contract platform, Ethereum's network of data is far larger than Bitcoin's focus on payments. By Etherscan As you can see, becoming Ethereum's default full node now requires at least a minimum. 800 Many G Space, become Ethereum. Archive All nodes need at least 13000 G Storage space.
Not only is the overall amount of data huge, but most of the data is stored in unformatted form, which makes it extremely difficult to process, index and query blockchain data. Therefore, thinking from the perspective of monomer blockchain, how to efficiently and cheaply store, quickly process and support massive access to blockchain data has become an extremely important research direction.
As early as the bitcoin white paper proposed, Satoshi Nakamoto for the state of the network explosion to do the solution in advance: they are Reclaiming Disk Space And Simple Payment Verification (SPV). Reclaiming Disk Space It allows nodes to prune the consumed historical data so as to reduce the data size of the whole network. This scheme can reduce the maintenance cost and participation threshold to a certain extent. However, due to the huge data volume of the whole network and the monomer blockchain of the account model, such as Ethereum, the data dimension and   maintained by the node; UTXO Different models, direct application degree will be more limited, but based on Reclaiming Disk Space The idea that the Ethereum community has been pushing and pursuing is to separate account state from the blockchain. Stateless Ethereum Plan,. SPV Mainly advocate light node Merkle Tree to verify the blockchain transaction data scheme, in addition to the implementation of the network's low participation threshold, to ensure the validity of the transaction data. As a result of SPV The light node simply downloads block header information for authentication, so it may receive fraudulent proof attacks.
To that end, it's now a joint venture with Celestia. Mustafa Al-Bassam, Mysten Labs nbsp; Alberto Sonnino And Vitalik used to be in. 2018 Fraud and Data Availability Proofs: Maximising Light Client Security and Scaling Blockchains with Dishonest Majorities, Maximising Light Client Security and Scaling Blockchains with Dishonest Majorities, The data availability of a single blockchain can be understood as a light node through a transaction without fully synchronizing the block data. Merkle Tree validation of transaction data.
For the execution layer of modular blockchain, the data of a single blockchain is transformed into on-chain data, and the transaction data of the execution layer is compressed and stored into on-chain data and on-chain data. On-chain data not only has direct requirements on performance and cost such as conventional storage query, but also relies on consensus mechanism accompanying on-chain data to ensure security. Thus, it is the development of execution-level products that enrich the data availability of individual blockchains and expand the context in which the data availability layer concept corresponds.
Before moving on, it is important to understand that the data availability layer and the data storage layer are not to be confused. The data availability layer emphasizes availability, thinking in terms of the availability of data. The data storage layer is to define the data storage and use performance from the perspective of computer memory, and pay more attention to the cost of on-chain storage, read and write efficiency, etc. Data availability is necessarily based on the notion that the data storage layer is extended, and here it is the availability that is extended by the consensus mechanism. In other words, Don't Trust me to Verify. Verify The corresponding is data availability.
Ethereum, now the preferred data availability layer for execution-level products, has its own Gas Model and Calldata Structure, there are the following obvious shortcomings: 1 , high data operation and storage costs; 2 Data storage capacity is limited; 3 Uneven distribution of network resources. To that end, Ethereum uses the EIP-4844 nbsp; Proto-Danksharding, Data Availability Sampling (DAS), Erasure Coding And Proposer/Builder Separation And proposed their own data fragmentation and state expansion schemes. In the future, Ethereum will introduce new ones. Blob Transaction types and additional data layers reduce the cost of dynamic storage on the current chain while ensuring data availability. As for other specialized DA Products are not only available in data sampling, Erasure Coding They also made breakthroughs in the field of data availability, such as Polygon Avail nbsp; Fast Sync Technology Celestia Sovereignty and interoperability. In addition to the data available layer of products, in the existing data storage layer, we can also see there are. BNB Eco New Storage Side Chain Greenfield, and Kvye And Arweave and other combination products.
Not your keys, not your crypto. In a blockchain network, a secret key represents ownership of a digital asset. In order to ensure the ownership of the key corresponding to the digital asset, the blockchain network must implement a strong consensus mechanism to ensure sufficient degree of decentralization and security. The consensus mechanism guarantees data that conforms to the transaction format of a single blockchain. For example, Bitcoin guarantees the transactions on it and the scripting logic built into the transactions. Ethereum guarantees. EVM Transactions that can be executed and validated. Moreover, because there are two types of consensus mechanisms (PoW and PoS) with obvious differences in the blockchain world, it is difficult to interoperate and combine and use different consensus among different monomer blockchains. In addition, even monomer blockchains that natively support multi-chain interoperability, such as Cosmos Polkadot and Polkadot are compatible with each other in terms of trade formats or consensus mechanisms, but there are still situations where consensus mechanisms are difficult to share.
Before entering the consensus layer products, let's understand and familiarize ourselves. PoW And PoS The development and current situation.
PoW The most common attacks on blockchain networks, roughly understood as using the computing power of the physical world to secure them, are. 51% Computing power attack and double flower attack. Therefore, only when the computing power of the network is large enough, the security of the network can be guaranteed. A lot of new ones. PoW Public chain, in the cold startup stage, due to the lack of early computing power, the network is easy to encounter security problems. To do so, they're either building up computing power over long periods of time and at high cost, or they're looking to traditions like Bitcoin. PoW The mining power of the network adopts the same PoW Algorithm for joint mining. Because the computing power of blockchain is essentially increased with the increase of block height, the combined mining/combined mining rents computing power through the encryption economic incentive mechanism. When the interests of the two public chains coincide and match, the combined mining/combined mining is attractive to miners. However, when the new PoW When there is a conflict between the interests of the public chain and the Bitcoin network, because the Bitcoin network has no way to sanction miners at the level of agreement, miners will generally take actions against others. PoW The act of a public chain.
For example, long ago, Namecoin The joint mining is carried out through the computing power of the Bitcoin network. Because the joint mining scheme will cause the benefit mismatch between the two networks in some scenarios, it is caused. Namecoin Potential risks. For the bit network side chain which realizes the function of intelligent contract RSK In terms of, although RSK It is optimized for the benefit of the Bitcoin network, but its own iterative development is limited by the non-Turing completeness of the bitnet, so the breakthrough in the joint mining is limited. In addition, for Quai Network From the beginning of the design, the multi-chain association was originally proposed. PoW, huddle for warmth at the computational level. Even so, Quai Networks & NBSP; It is also just to share the agreed cold start-up costs equally, also cannot do. PoW Reuse and combination of consensus mechanisms.
PoS The core of consensus mechanism is the use of rights and interests protection network, the value of rights and interests will determine the overall value of the network, only high enough value of rights and interests to protect the high value of the network. Now popular. PoS The mechanics are based on PBFT The improved essence is still the proof of equity. Common PoS The network has a well-known. Cosmos And Polkadot. With the mechanics of minimizing trust, Cosmos As Hub is a consensus mechanism that does not actively interfere with the ecological application chain. Cosmos Ecological application chain can reuse the whole ecological development stack, but when maintaining the corresponding application chain network, the establishment and maintenance of network validator set is a very high threshold and cost, which is also the cost of trust and security.
Many application chains will generally be attracted by air drop. Cosmos The verifier provides high inflation incentives to encourage the verifier to pledge the protection network. To reduce the cost of establishing consensus mechanism and improve the security of application chain, Cosmos 2.0 Propose various improvement schemes, for example, can be borrowed. Cosmos Secure sharing for the application chain ICS, Space Mesh that allows consensus sharing for application chains, etc. In addition, Cosmos Ecological Babylon There are also attempts to integrate the Bitcoin network. PoW Consensus security Introduction Cosmos Ecology is used to ensure the security of the application chain. For Poca, we all know that it combines a strong on-chain governance model with a cutting-edge consensus philosophy.
It can be understood that Poca directly extends the guarantee boundary of consensus mechanism to other chain transactions through the mechanism of parallel chain card slot auction. Undeniably, these mechanisms have advanced ideas in terms of reusing consensus. However, due to the mismatch between the efficiency of on-chain governance and the strong demand of consensus, the Poka parallel chain has faded out of view.
Now, let's go back to after the merger. PoS The consensus mechanism of Ethereum. To Tai Fang is an excellent consensus layer product resources, many years PoW Precipitate development has led Ethereum to accumulate high value, explore and iterate for years. PoS The mechanics, coupled with Ethereum's sophisticated smart contract platform and the burgeoning Ethereum executive layer products, have led to the adoption of the PoS Ethereum is ripe for a new generation of consensus-layer products. Based on the logic of the existing Ethereum pledge, we can reuse the pledged Ethereum through the design of reasonable and effective incentive and punishment mechanism, and use this part of Ethereum to protect other types of networks, such as prophetic machine network, bridge network, etc. And we eigenattribute them. After years of research on the track, it has recently published a corresponding white paper, formally proposed. Restaking The concept, and from slashing Mechanism describes the function and design of its own network.
In addition, the recently hot Ethereum liquidity pledge derivatives track products, essentially with a large amount of pledge Ethereum, once the appropriate consensus layer products, liquidity pledge derivatives track products will be seamlessly involved as consensus providers.
Service-oriented micro-service architecture is popular in modern software development. By dividing the application program into services with independent functions and features, each service can be developed, deployed and run independently, and each service can be combined flexibly by means of communication and data sharing, so as to achieve higher scalability, flexibility and maintainability. The development of microservice architecture is gradually mature and perfect. Although there are still some challenges and problems in practice, such as distributed transaction, service governance, security, etc., these problems are gradually solved with the further maturity of technology and accumulation of experience.
Modular blockchain has many similarities with micro-service architecture. With the continuous development of blockchain, it will also become an important direction of blockchain technology. At present, the products of the executive layer are constantly taking on more functions of transaction calculation, and achieving excellent results in various indicators such as user data and transaction data. The data available layer and consensus layer are advancing in their respective program fields, while the functions of the settlement layer need to be developed. The potential flexible combination between them will bring more unlimited potential. In the future, we have reason to believe that modular blockchain will bring more innovation and opportunities, and make important contributions to promoting the application and development of blockchain technology.