All decentralized applications (DAPP) need to be built on an underlying chain. Different business scenarios have different requirements on the performance and consensus mechanism of the underlying public chain. Some applications even need to build their own underlying chain (including private chain, alliance chain and public chain, etc.).

However, developing an underlying chain that adapts to its own business often requires a certain technical threshold and time. There are many businesses with landing scenarios that do not have technical personnel who understand the underlying blockchain. At the same time, the business needs to go online as soon as possible. Even if there is, it is difficult to build a completely suitable underlying chain in a short time.

The NULS to be introduced in this article (https://nuls.io/), intends to "modularize" the underlying chain, lowering the threshold for developers to quickly customize their own underlying chain.

NULS is a customizable blockchain infrastructure, a global blockchain open source community project, and its foundation is registered in Singapore. The team built a main chain and modularized the main components of the underlying chain. These components are reusable and open source. Developers can customize a different underlying chain by assembling and modifying different modules.

2. Modular architecture:

The sponsor and the white paper summarize the characteristics of NULS from four aspects:

1. Consensus mechanism:

NULS named the consensus mechanism of its main chain POC (Proof-Of-Credit, credit-based consensus mechanism), which is a bit like DPOS. Retail investors who hold less currency can entrust the currency to the agent, and the agent can form a node to participate in the consensus.

The historical number of blocks produced by a node, violations and correctness of blocks will affect the node credit. When the credit of the node meets the standard, a certain deposit can be locked to join the consensus. After the consensus nodes are reordered, blocks will be produced in each round.

The difference between the role of the agent and the principal in the POC consensus mechanism

2. Modular architecture:

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Developers can change the consensus mechanism, block size, block mechanism and storage mechanism according to their own performance and security requirements, and build the underlying chain into different forms such as public chain, alliance chain, and private chain.

3. Multi-chain parallelism:

Multi-chain parallelism is a mechanism to improve the performance of the blockchain, which weakens the concept of the main chain. Different chains can handle different businesses, and theoretically can continue to expand in parallel. The Nuls community will develop different cross-chain consensus modules for different sub-chains. Nuls uses cross-chain consensus modules to connect different chains together to achieve cross-chain communication.

Some nodes of the main chain and some nodes of the sub-chain form a cross-chain consensus domain. Nodes in the cross-chain consensus domain reach a consensus on cross-chain transactions, convert the cross-chain data protocol and share cross-chain data to other peer nodes.

4. Smart contract:

According to the project white paper, Nuls has built-in NulsVM to handle smart contracts. The smart contract module is between the external service module (such as the RPC module) and the underlying facility module (such as the network module, storage module, account module, etc.), and the latter provides the underlying support for it. Nuls has designed some smart contract templates, and its interpreter will support a variety of high-level programming languages, and developers can choose freely.

Zhang Xing introduced that application-level products can be directly deployed on the public chain of Nuls, or the data of the private chain can be audited on the public chain. The former can share the performance improvement of Nuls bottom layer upgrade, and the latter can obtain technical support from the team. Nuls is currently in the development stage. It is planned to launch the test network in March this year and the official network in May.

There are currently about 7 core developers of the NULS project (see the official website for details). The initiator and chief developer, Zhang Xing, graduated from Tianjin University and has been engaged in data security work in the financial field for 6 years. He is a full-stack engineer and once worked for Jiangnan Keyou, an information security technology research and development company, leading the company's product design and R&D work.

(I am Aloe Vera, a reporter from Odaily. Please add WeChat 1012387983 for breaking news and communicating. Please note your name, unit, position and reason.)