The first DA layer on Bitcoin, a brief analysis of Nubit architecture and highlights

DA (Data Availability) simply means that the block producer publishes all transaction data of the block to the network so that validators can download it. We say the data is available if the block producer publishes the complete data and makes it available for download by validators. The DA layer is a layer abstracted along with the expansion needs of each blockchain and the higher requirements for DA. We have seen a large number of projects emerge in the market, such as Celestia, EigenLayer, NearDA, Avail, etc. These projects often establish their own schools, pull the banner, and vow to make their own reputation.

After the Bitcoin ecosystem is gradually injected with funds, various technical routes related to Bitcoin are also booming. L2, staking, introducing BTC to Ethereum or Solana’s DeFi projects have all appeared on the stage, and BTC’s Native DA projects have also begun to receive market attention.

Just recently, NubitNubit completed a $3 million Pre-Seed round of financing, with dao5, OKX Ventures, Primitive Ventures and others participating in the investment. The team said it is preparing for the launch of the mainnet.

What is Nubit?

Nubit is a scalable Bitcoin-native DA layer, security protected by Bitcoin. Nubit can effectively expand the data capacity of Bitcoin and provide support for applications such as Ordinals, L2, oracles, thereby expanding the scope and efficiency of the Bitcoin ecosystem. It aims to fully inherit the security of Bitcoin, including economic security, resistance to tampering, resistance to censorship, etc.

When the cryptocurrency market is hot, the fees for Bitcoin transfers or transactions are often quite high, and there may even be a lot of congestion. Last year's surge in silver market demand caused Bitcoin to store more than 14GB of data, incurring extremely high costs. Data from its official website shows that Nubit can reduce transaction fees by more than 95% and increase the amount of data noise by more than 100 times.

Nubit Architecture

Nubit mainly consists of four basic components, validators, trustless bridges, full storage nodes and light clients.

Among them, the verifier node mainly uses the Byzantine Fault Tolerance (PBFT) consensus algorithm, and its main task is to propose, verify and ensure the integrity of transactions. The trustless bridge acts as an intermediary, charging users storage fees and distributing rewards to validators through payment channels. The full storage node is mainly responsible for the reliable storage of all data after receiving block data from the validator. The light client obtains the blocks broadcast by the validator, including data commitments, and may randomly initiate requests to full storage nodes to verify DA.

Nubit Highlights and Features

Nubit still adheres to the semi-synchronous network assumption. Introducing NuBFT, a consensus algorithm optimized for DA depth. NuBFT is a variant of the BFT consensus algorithm that combines the data partitioning process based on RS encoding and the generation of KZG. Even if some data nodes are damaged, the original data can be recovered using RS encoding.

In addition, the KZG submitted to Bitcoin ensures the validity of the original data. By integrating RS-encoded block division and KZG generation into the consensus algorithm, the integrity, availability, and scalability of stored data are directly linked to the consensus process, significantly enhancing the "robustness" of the entire DA system.

It is worth noting that Nubit uses BTC as the main token of the consensus protocol, inheriting the economic security of Bitcoin through Bitcoin’s native staking mechanism such as Babylon. In contrast, general-purpose DA layers like Celestia introduce additional trust assumptions outside of Bitcoin using their network tokens.

In terms of data availability, in order to solve potential network outages caused by node data encoding errors, Nubit adopts a hybrid approach, integrating full nodes and light nodes to ensure data integrity. First, Nubit uses KZG as a proof of validity to ensure DA, reducing memory, bandwidth, and storage requirements while maintaining simplicity. Even in the event of a complete collapse of the Nubit network, nodes can still use full nodes and KZG commitments submitted on Bitcoin for data recovery. To further enhance network scalability, Nubit employs light nodes equipped with Data Availability Sampling (DAS). This addition expands the block size to meet growing demands for data availability.

However, unlike other Bitcoin L2 solutions, Nubit does not have a smart contract execution layer.

In terms of trustless cross-chain bridges, previous Bitcoin L2 usually relied on centralized cross-chain bridges, which caused potential security vulnerabilities due to Bitcoin’s specific architectural limitations. Nubit directly chose Lightning. network, enabling Nubit to build a secure and trustless bridge into the Bitcoin ecosystem.

Nubit uses Bitcoin payment channels for network fee settlement, also a key differentiator from other BTC bridge solutions. Nubit users are not required to incur any pre-deposit requirements. Instead, they handle transaction fees directly within the state channel of each transaction, ensuring that the security of user funds is directly tied to the security of Bitcoin itself. In addition, Nubit is designed to allow emergency withdrawals, and even if Nubit ceases operations, users can recover their funds by closing the Bitcoin payment channel.

Summary

In the past BTC technology practice, to a certain extent, SegWit, Taproot, etc. have more or less enhanced Bitcoin DA, but the emergence of Nubit seems to be just right. It's time, because at that time the modular and L2 wave was still not emerging, and a completely new solution is now on the horizon. After Nubit has been working non-stop with projects such as Babylon, Merlin, and BounceBit, it said it will officially launch the mainnet later this year. Future development deserves attention.

The above is the detailed content of The first DA layer on Bitcoin, a brief analysis of Nubit architecture and highlights. For more information, please follow other related articles on the PHP Chinese website!