For any public blockchain to be safe and efficient, the consensus mechanism is the key point to consider.
A good consensus mechanism ensures the security of the network and the distributed data. It also helps avoid malicious attacks. In addition, a good consensus mechanism is crucial in order to have the community participating effectively in network activities, especially by incentivizing the community to act autonomously and to enter a virtuous circle.
Blockchain technology is still in its infancy and researchers are still exploring its potentialities. The current level of progress does not yet allow any actual large-scale commercial application. The InterValue project uses a DAG-based Gossip consensus mechanism with self-designed shards. The consensus mechanism features a variety of technologies including DAG, BA-VRF, layering, and sharding.
The InterValue project aims to create the infrastructure of a “Global Value Internet” and solve the functional problems of current blockchain infrastructures. These problems include network congestion, high transaction fees, potential quantum attacks, absence of communication anonymity, low cross-chain interoperability and excessive storage requirements. The optimization and improvement of protocols and mechanisms at various levels will enable the achievement of this “Global Value Internet”.
As an infrastructure of the blockchain 4.0 era, InterValue serves as foundation for a wide range of value transfer applications. At the same time, it provides a multi-level platform for the development of all kinds of Dapps and a viable technology frame for building a Global Value Internet.
W Finance had the opportunity to interview the InterValue project team. In order to help the public understand InterValue’s technical strengths, W Finance has conducted in-depth discussions on how the InterValue consensus mechanism stands out among its peers. The following is the interview transcript:
How does InterValue’s two-layer consensus mechanism solve the problems of the current blockchain space?
InterValue noticed that most of the existing blockchain technologies are unable to adapt to the requirements of large-scale commercial applications. The main reason is that their consensus mechanism does not provide a good trade-off between decentralization and scalability, as Bitcoin and Ethereum show us. Ethereum has a good degree of decentralization, but the transaction speed is lower; EOS has a higher transaction speed, but the degree of centralization is higher.
The main innovation of the two-layer consensus mechanism is the separation of the shards during the process of establishing consensus. Specifically, full nodes (on the top layer) are responsible for periodically dynamic shards composed of local full-nodes (lower layer) who work on reaching consensus. Local full-nodes achieve consensus on the transactions within one single shard, and the global ledger is synchronized between the nodes by running the “gossip” protocol.
The main advantage of this design is that DAG and BA-VRF protocols are used between full-nodes to ensure the fairness and decentralization of the shards. The bottom part of full-nodes uses the DAG consensus to achieve high transaction throughput, and the number of shards is unlimited.
At present, the InterValue team has implemented the HashNet consensus mechanism in InterValue’s TestNet 2.0, and asked the Ministry of Industry and Information Technology's Tyre Lab to test the V2.0. The performance test gave the following results:
Pure performance test exceeded: 2.4 million TPS across 10 shards, Actual transaction performance: 200,000 TPS across 10 shards
Wide geographic distribution test: 420,000 TPS
Post-signature verification performance test: 100,000 TPS across 10 shards
Single transaction confirmation time: less than 3 seconds.
Malicious data has no impact on transaction performance, the system’s fault tolerance algorithm met the expectations.
According to the CAP theory, it is impossible to have a safe decentralized and highly scalable public chain. As the world's first practical blockchain 4.0 project that supports large-scale applications, how does InterValue balance decentralization, security, and scalability?
How to achieve a good balance between decentralization, security, and high scalability is an issue that has been discussed at the beginning of this project.
InterValue’s HashNet consensus sharding is a key factor in achieving this balance. HashNet adopts a double-layer gossip topology framework to form a distributed accounting system through the method of “intra-shard autonomy and inter-shard collaboration”. Full nodes are responsible for maintaining node topology and shards. The local full nodes are responsible for transaction verification, transaction consensus, transaction storage, data consistency, and maintenance. A good balance between decentralization and scalability is achieved by decoupling shards and consensus.
In order to improve system security, InterValue uses anti-quantum hash and signature algorithms, transactional anonymity protection and other means to protect transaction security and user privacy.
InterValue transactions have high concurrency and fast transaction confirmation. This enables to quickly build an ecosystem for different application scenarios. What do you think is the difference between the consensus mechanism of the blockchain 4.0 compared to blockchain 3.0?
The main advantages of InterValue's HashNet consensus mechanism include: (1) High transaction throughput, which is expected to support the deployment large-scale commercial applications and has achieved a peak transaction speed of over 1,000,000 during various tests. (2) A better balance between decentralization and scalability through a two-layer consensus mechanism.
We have noticed that DAG's data structure can result in a high TPS main network. How does InterValue guarantee the ultimate consistency of node data within the main network? In short, when InterValue's last transaction is fully confirmed, how many confirmations do you need? How many nodes does it need to go through? How to solve the problem of malicious nodes?
The consistency of the InterValue node data is essentially ensured by an asynchronous PBFT algorithm. The node synchronizes the generated transactions through the gossip protocol, and verifies the consensus of the transaction consistency by verifying the path that the transaction is witnessed.
After InterValue's last transaction has been confirmed, it has to be approved by at least 2/3 of the local full nodes within the shard. When the number of malicious nodes is less than 1/3, the consensus will not be affected.
In order to prevent malicious local full-node collusion within the shard, InterValue periodically replaces the local full nodes in the existing consensus with other nodes called “candidates”. In order to prevent double-spending transactions, each light node can only send a transaction request to a local full node according to the result of the ID suffix matching. The data is sorted according to its consensus timestamp, thereby ensuring the authenticity of the data.
In order to prevent nodes from maliciously synchronizing large-scale data to cause service unavailability problems, each connection automatically limits the number of events it sends.
As far as the security of the public chain is concerned, there is still no public blockchain that everyone is satisfied with. InterValue may well be the next unicorn chain. Does InterValue's unique self-evolving ecosystem reflect its consensus mechanism advantage?
Yes. The top-level goal of the InterValue ecosystem is to be able to build applications in fields such as digital currencies, distributed social platforms, distributed storage, divergent contracts, and other non-financial areas. In addition, it can promote the development of cross-chain communication and multi-chain convergence.
From the perspective of financial and non-financial applications, InterValue’s advantage lies in its strong scalability and high TPS, which are allowed by HashNet consensus mechanism. From the perspective of cross-chain communication and multi-chain convergence, the two-layer architecture mode of the consensus mechanism enables interactions with other public blockchains. This connection is made through full nodes.
The entire main network of InterValue is based on the DAG data transmission mode. Full nodes are selected through a DPOS mechanism and the local full nodes through a combination of POS+POW+POB+POO. Besides, it features Byzantine fault tolerance. InterValue has many technical advantages when it comes to building commercial public chains. How can the team achieve the most advanced technology and make the most of the technological advantages?
When the team started to work on the InterValue project, its original goal was not to go after the public’s hopes but to truly innovate.
Blockchain is essentially a distributed ledger system. The challenge of the public blockchain is to achieve the best balance between decentralization, scalability, and security. Due to decentralization, scalability, and security constraints, it is necessary to comprehensively consider the specific design difficulties at each level, and not just focus on a specific point.
In the process of developing InterValue, the team has encountered various specific problems. The current technical solutions have been achieved through continuous development. In the follow-up development process, InterValue will continue to keep up with the technology frontier and improve the security, scalability, and decentralization of the system in many ways.
The consensus mechanism is crucial and is the core of the blockchain technology. It largely determines the degree of mutual trust between the nodes of the system. In addition, it also determines the trust of users in the data on the blockchain.
For a given blockchain system, whether the design of the consensus mechanism is good and bad directly determines the system's work efficiency, operating costs, security, stability, and even directly determines the value of the system.
For a given public blockchain project, the most important part is the research. Undoubtedly, the InterValue team did it and implemented a unique consensus mechanism. Every in-depth tech-related discussion highlights their enthusiasm and determination to develop the blockchain 4.0.
W Finance believes that InterValue will leverage on HashNet consensus to impress people and attract users. We hope that InterValue becomes the leader of the public blockchain space in the future.