The Evolution of Blockchain Technology: Sui Lutris's Innovative Solutions

Blockchain technology has made significant progress since the advent of Bitcoin. With the emergence of new application scenarios such as games and NFTs, the industry is continuously exploring ways to enhance technical efficiency, especially in handling high load and real-time latency. L1 blockchains face two major challenges: first, achieving high throughput while maintaining low latency, and second, ensuring the long-term stability of consensus protocols. Additionally, decentralization must be maintained through the dynamic participation and reconfiguration of validating nodes.

One way to increase throughput is to adopt a DAG-based consensus protocol, such as Narwhale/Bullshark used by Sui. These types of protocols can handle a large number of transactions simultaneously, making them suitable for applications like gaming and NFTs. However, DAG-based protocols usually result in a few seconds of latency, which can be a high time cost for regular transfers or gaming operations.

On the other hand, consensus-free protocols (such as FastPay) show great potential in reducing latency and scalability. These protocols can quickly process transactions without consensus, eliminating the need for total ordering of independent transactions that are processed in parallel. However, they are limited to a class of constrained simple Blockchain operations, which restricts the achievable smart contract functionality, and dynamically reconfiguring the changing set of validators may pose challenges.

Despite the enormous potential of these methods, they have not yet been applied to production-level Blockchains and have only been published at academic conferences, without widespread adoption by the Blockchain community. Sui Lutris, as a protocol supporting Sui, combines DAG-based consensus with non-consensus methods to achieve the best of both worlds: sub-second latency and sustained throughput of thousands of transactions per second. Sui has not only accomplished these two tasks but has also maintained the ability to express complex contracts on shared objects, generate checkpoints, and reconfigure the validator set across periods.

Sui Lutris adopts a unique approach that combines the two aforementioned solutions. To ensure the security of single-owner asset operations, the system employs a consistent broadcasting protocol among validators to achieve latency below consensus. For complex smart contracts running on shared objects, Sui Lutris relies solely on consensus processing. Additionally, it supports network maintenance operations such as defining checkpoints and reconfiguring validators. This innovative strategy provides a solution that balances efficiency and security when handling transactions in a replicated Byzantine environment.

The transaction lifecycle of Sui Lutris includes the following steps:

1. The user creates and signs the transaction and sends it to the Sui Lutris validation node.
2. The verification node conducts validity and security checks, signs, and returns to the client.
3. The client collects the responses from most of the validating nodes to form the transaction certificate.
4. The certificate is sent back to all validating nodes for confirmation.
5. Transactions involving exclusive objects can be processed immediately (direct fast track).
6. All certificates are forwarded to the DAG-based consensus protocol.
7. The total order of consensus output certificates, verifying that nodes execute transactions containing shared objects.
8. The client collects the responses from the validation nodes and assembles the effect certificate as proof of transaction settlement.
9. Form checkpoints for each consensus submission to drive the reconfiguration protocol.

In addition to the main trading process, Sui Lutris also provides multiple features to support production-level Blockchain:

1. Implement checkpoint protocol to generate a causal history of all transactions in the system for complete auditing and synchronization.
2. Support reconfiguration at the end of each epoch to ensure all final transactions are included in one epoch.
3. Safely "unlock" mistakenly locked assets at the end of the epoch, minimizing damage caused by vulnerabilities.

Sui Lutris supports Sui and aims to manage the value of a large number of user assets. The protocol provides security and liveness guarantees in a standard distributed system model, capable of handling partially synchronous Byzantine participants.