With the continuous development of blockchain technology, modular architecture has proven to be an effective way to solve the impossible triangle problem of blockchain. B2 Network is committed to utilizing modular design to promote the unlimited expansion of the Bitcoin ecosystem, thereby achieving the perfect balance of scalability, security and decentralization.
Modular blockchain architecture: a trend to solve scalability challenges
The development of blockchain technology has always been restricted by scalability, security and decentralization, forming the famous "blockchain impossible triangle problem". To solve this problem, the modular blockchain architecture emerged, which provides a new way to improve the scalability of the blockchain system by decoupling the monolithic blockchain stack.
Judging from the development roadmap of Ethereum, after the sharding solution DankSharding is successfully deployed to the Ethereum main network in the future, the Ethereum main network will maintain a consensus layer responsible for block sorting and final confirmation, and responsible for storing the data required to verify the validity of state transitions. The data availability layer, the asset settlement layer responsible for verifying Rollup status data and processing fraud proof/validity proof, and the execution layer responsible for processing transactions and status updates will be completely handed over to Ethereum such as Arbitrum, Optimism, Starknet, ZkSync, Polygon, etc. The completion of the Ethereum ecosystem L2 and the sharding solution DankSharding will completely transform Ethereum into a modular blockchain architecture.
Although the modular blockchain architecture brings huge potential to Ethereum, its long upgrade path cannot be ignored. At the current stage, Ethereum is preparing for the Cancun upgrade EIP4844 to add block space dedicated to storing state data submitted by Rollup L2. This is only the first step in realizing the final sharding solution DankSharding. However, this has not stopped other projects from implementing modular architecture in advance to realize their vision.
And because the Bitcoin network is more secure and decentralized, Bitcoin is more suitable as the final settlement layer. However, Bitcoin's network load, storage limitations, and non-Turing complete characteristics prevent Bitcoin from completing the functions of the data availability layer and execution layer. Therefore, a modular blockchain architecture design is introduced, using Bitcoin as part of the consensus layer, data availability layer and settlement layer. The functions of the execution layer are shared by multiple Rollups to achieve the expansion of the Bitcoin network. Modular blockchain architecture design will be an important part of the ecological expansion of Bitcoin.
B2 Network modular architecture design concept
The overall architecture of B2 Network adopts a modular design, with zk-rollup as the execution layer and B2 Hub combining decentralized storage and the Bitcoin network to form the consensus layer, data availability layer and settlement layer.
Bitcoin cannot serve as a settlement layer independently due to its own transaction throughput limitations, storage limitations, and non-Turing complete scripting mechanism. The emergence of B2 Hub solves this problem by connecting rollup, decentralized storage and the Bitcoin network, using rollup as the execution layer, B2 Hub + decentralized storage + Bitcoin as the data availability layer, and B2 Hub + Bitcoin Serves as the consensus layer and settlement layer.
Specifically, B2 Hub stores rollup details in a decentralized storage protocol and aggregates rollup data and proofs. The aggregated information will be written into the Bitcoin network, using the powerful computing power and decentralized characteristics of Bitcoin, as well as the multi-copy storage of decentralized storage and the economic incentives of B2 Hub to jointly ensure the security and availability of rollup data. . Considering the non-Turing completeness of Bitcoin, B2 Hub adopts zk proof verification commitment and challenge mechanism to ensure that the Bitcoin network can confirm and prove the state transition of rollup, thereby realizing the settlement confirmation of rollup on the Bitcoin network.
Technical features
Rollup as the execution layer: B2 Network uses zk-rollup as the execution layer to ensure the privacy and security of transactions through zero-knowledge proof technology.
B2 Hub serves as the data availability and settlement layer: B2 Hub integrates the decentralized storage protocol and the Bitcoin network, and is responsible for storing rollup detailed data and providing data availability guarantees. At the same time, it completes settlement confirmation through the Bitcoin network to ensure the validity of the transaction.
Unlimited horizontal expansion: B2 Hub uses aggregation and challenge mechanisms to achieve effective management and verification of data and proofs from multiple zk-rollups, thereby achieving unlimited horizontal expansion of the Bitcoin ecosystem.
Positive impact on the Bitcoin ecosystem
B2 Hub achieves data availability guarantee and validity proof/fraud proof provision by connecting rollup, decentralized storage and Bitcoin network. It supports multiple zk-rollups and sends rollup data and zk proof to B2 Hub. B2 Hub stores rollup’s detailed data in a decentralized storage protocol, aggregates the data and proofs, and then submits the aggregated information to the Bitcoin network. In this way, B2 Hub ensures the data availability of all rollups, verifies zk proof, generates aggregate proof, and submits it to the Bitcoin network, ensuring the validity of all rollup states through the challenge mechanism.
The design of B2 Hub also helps prevent Bitcoin from affecting its security and decentralization due to second-layer expansion. As more and more Bitcoin second-layer solutions emerge, each solution needs to submit data or proof to the Bitcoin network. However, this will lead to transaction throughput limitations and storage limitations of the Bitcoin network, thereby affecting the normal operation of the Bitcoin network. By aggregating rollup data and proofs, and uniformly submitting data availability proofs and state transition proofs to the Bitcoin network, B2 Hub achieves unlimited horizontal expansion without affecting the operation of Bitcoin proofs. This design ensures the security and decentralization of the Bitcoin network while providing greater space for the development of the entire ecosystem.
future outlook
B2 Network will continue to work on the optimization and expansion of modular architecture and continuously improve the scalability, security and decentralization of the Bitcoin ecosystem. At the same time, B2 Network will cooperate with more infrastructure partners to provide complete infrastructure and technical support for rollup builder, and jointly promote the vigorous development of the Bitcoin ecosystem.
Through the design and implementation of modular architecture, B2 Network will inject new vitality and power into the future development of the Bitcoin ecosystem and promote Bitcoin to become one of the world's leading blockchain infrastructures.
