Original text: What Blockchain Layer 3 scaling brings to the table

Translation and proofreading: Starknet Chinese Community

📑 Please indicate the source for reprinting🕹️

Quick Facts

• L3 application chains provide higher customization and lower costs for dApp development

• L3 benefits include customizability, reduced costs, and avoidance of congestion

• StarkWare-backed Herodotus integrity verifier is a major leap forward in enabling L3 scaling

Vitalik Buterin once described Layer 2 (L2) as “the ultimate battlefield of action.” Due to its ability to scale Ethereum, L2 has become an integral part of the Ethereum ecosystem.

Currently, a new layer of network developed based on L2, namely L3, is causing heated discussions. However, if L2 is enough to expand Ethereum , then you may ask, what is the use of L3?

Don’t worry, we will guide you through the details. Through this article, you will have a deeper understanding of L3 and how it adds a new layer of network scalability on top of L2, and more importantly, it also adds Customization capabilities. L3 is actually easier to understand than you might think. Let’s get straight to the point.

Why choose L3?

Imagine a congested highway. This situation is similar to conducting transactions directly on an L1 blockchain such as Ethereum, that is, every transaction must be executed on L1. The more transactions there are, the slower the speed. This is especially bad during peak times when everyone is transacting on Ethereum (think of the CryptoKitties craze, when there were concerns that a 6x increase in total network requests would bring the network to a standstill). As network activity increases, users' transaction fees will also increase.

L2 solutions are like express lanes on a highway. They move some traffic off the main road, making it faster. For example, a transaction on Starknet is much faster than a transaction executed directly on L1. Much cheaper (about $0.01 ).

Starknet does this by removing the heavy computation associated with transaction execution from Ethereum. Starknet executes transactions on the cheaper L2, then bundles those transactions together and generates a certificate proving their validity, which is then This proof is sent along with the state differences to L1 for verification.

This means that you can build dApps on Starknet and achieve cheaper and faster transactions than directly on Ethereum. But what if you want to further customize your dApp, or even complete some functions that cannot be achieved directly on Starknet? ? What if you want to fine-tune the block size, expand the data availability (DA) options, or create your own native token?

This is where L3 comes in.

L3, as a network layer built on L2, is usually developed as an application chain or a chain tailored for a specific application or purpose. L3 application chains provide greater customizability for builders who seek full control over their dApp logic. L3 can also further reduce transaction costs because it settles on L2 (which is cheaper than L1).

How does L3 work?

Just as L2 offloads transaction execution from Ethereum (L1), L3 offloads transaction execution from L2 to L3. It executes transactions on L3, batches them together, and then sends proofs to L2 to prove their validity.

This is the key to reducing costs: L3 publishes transaction data on L2 instead of L1. On L3, L2, which has a much lower cost than L1, will serve as the base layer, and then transmit minimal transaction data to Ethereum. The settlement is carried out on the network layer of L3, and its transaction data will be further compressed by L2 before being transmitted to Ethereum, so L3 saves costs compared to L2.

How to reflect customizability?

Builders who develop L3 application chains are not just building an application on an existing chain, but building the chain itself as an application. They can match various aspects of the chain itself to the application they are building.

Starknet’s L3

With the support of StarkWare, storage verification innovator Herodotus launched an integrity verifier in April 2024, taking an important first step in bringing L3 application chains to Starknet.

With this new validator, developers can verify executions of Cairo programs executed elsewhere on Starknet, just as they verify Starknet executions on Ethereum.

Since L3 application chains will be settled on Starknet, they need to be able to verify Stone (and Stwo in the future) proofs on Starknet to prove the validity of the transactions they execute on L3. Integrity verifiers make this possible. Potentially, paving the way for L3 scaling on Starknet.

The L3 Starknet application chain sends the proof to the public Starknet for verification. The public Starknet then further compresses the proof and transmits it to Ethereum.

What key advantages will L3 bring to Starknet?

We have already talked about some of the key benefits of L3 extensions, namely customizability, lower costs, and avoiding congestion. Here, let’s explain why these benefits are important:

• Customizable : Overall, L3 application chains provide developers with greater flexibility than public L2 application chains, maximizing their customization capabilities in various aspects of the application. For example, consider block size, latency, data availability mode , and even implement features that are not supported by the public L2. For example, if builders want to launch their own native tokens to pay for their dApps, they can implement it on the L3 application chain.

• Reduced costs : When Appchain is built as L3 and settled on Starknet instead of Ethereum, costs are significantly reduced. Starknet also further compresses transaction data and transmits it to Ethereum, further reducing costs. Benefiting from this, it becomes economically feasible to develop more complex use cases, such as high-frequency DeFi transactions, supply chain management, and fully on-chain games.

• Avoid congestion : Application chains provide a more stable transaction environment (critical for real-time applications such as games), and once blockchain is widely used, it can avoid potential network congestion problems on public L2.

The Future of L3

L3 expands the possibilities of blockchain, provides more customizable options for dApp builders, and reduces transaction costs. As L3 takes hold in the blockchain ecosystem, developers will find ways to implement their The best approach is to make it run harmoniously on top of L2 and minimize the disconnect between the two.

The integrity verifier of Herodotus supported by StarkWare is a major leap forward in achieving L3 expansion on Starknet. At the same time, StarkWare is also promoting the development of other tools to make it possible to build L3 application chains on Starknet, and there will be more development in the future. .

Follow us on Twitter to stay up to date.