Aggregated Blockchains Fix the Layer 1 vs. Layer 2 Debate by Unifying Web3

The Internet didn’t just fall out of a coconut tree. Early on, in the pre-Internet-as-we-know-it-now era, there were many isolated networks. These networks were fragmented, they couldn’t talk to one another, and their users were isolated, too. 

Sound familiar?

The Internet really became the Internet when internetworking was defined and developed, with the W3C pushing standards that matter, like HTML, HTTP, and CSS, allowing communication and messages to be passed seamlessly, all across the world.

Right now, the blockchain landscape resembles this bygone pre-Internet era. Crypto is fragmented across thousands of chains, both L1s and Ethereum-focused L2s, of many varied execution environments and consensus mechanisms. 

Such fragmentation fundamentally hinders mass adoption. 

As we’ve noted before, no single monolithic (read: integrated) chain, no matter how many nodes it spins up, can handle an Internet-level load of transactions. State bloat (storing too much data) and state contention (processing too many transactions that touch the same state) will always be a problem. On the other hand, the wonders of modular ecosystems, like what’s found in Ethereum L2s, are stymied by fragmentation—even when these modular chains are proposed to be part of an interconnected megachain.

But there’s a way forward, with an aggregated approach: Enter the AggLayer, the TCP/IP moment for Web3.

The AggLayer’s architecture

The purpose of the AggLayer is simple: aggregate sovereign chains in order to unify liquidity, users, and state. It is designed to be as minimal and non-invasive as possible, a neutral public good.

With a core set of contributors from various ecosystems, the AggLayer imposes no extractive fees on aggregated chains (aggchains), requires no architecture for connected chains, and will enable fast, cross-chain fungible assets.

How will it do this? 

The AggLayer leverages zero-knowledge (ZK) proofs for a secure cross-chain ecosystem, enabling seamless communication, asset transfers, and data sharing across a diverse network of chains—just like how TCP/IP revolutionized the Internet.

At an extremely high level, you can think of three core characteristics for the AggLayer:

• A unified bridge, to which sovereign chains can connect for fungible cross-chain assets
• The pessimistic proof, a special ZK proof and accounting mechanism that ensures no single chain can withdraw more from the bridge than it has deposited
• Secure, cross-chain communication and advanced compute logic that enables unified liquidity, state, and users for aggchains.

A common misconception is that AggLayer is “just a bridge,” similar to existing interoperability solutions. 

This isn’t the case. Many existing third-party bridges facilitate token transfers or message passing between chains, but they do so by introducing new security assumptions for users, and often rely on wrapped assets that further fragment cross-chain liquidity. 

The AggLayer offers a trustless mechanism for unifying liquidity and state without the security risks associated with many third party interoperability solutions: a unified bridge and the pessimistic proof. With the unified bridge, where the AggLayer sees a multiplicity of chains, Ethereum sees just one shared contract—laying the foundation for one critical component of universal native assets. The pessimistic proof, on the other hand, provides a cryptographic guarantee which ensures that, even if a chain’s security is compromised, it cannot drain funds from other chains.

So even though the pessimistic proof can’t guarantee that a chain is doing correct internal accounting, it can ensure that it doesn’t rug other chains.

With this ZK super power, the AggLayer allows any chain to connect to the AggLayer. 

So no, it is not only Polygon CDK chains that can join. In reality, the AggLayer is inclusive. Already, core contributors are working to expand beyond EVM chains, to Move, Cosmos, and beyond—bringing all these chains into an aggregated, unified ecosystem.

But wait, how is this different from other interoperability solutions?

Although the AggLayer enables interoperability, it is not merely an interoperability solution, nor another mega-network of networks

The AggLayer is something new: an aggregated solution.

By aggregating chains and posting finality to Ethereum, the AggLayer unlocks cross-chain settlement. With emerging coordination mechanisms, like shared sequencers, the AggLayer will be able to handle extremely fast, atomic bundles of transactions. 

That means settling multiple transactions, across different chains, at the same time. You can read more about how this works, logically, in Brendan Farmer’s original post, here.

Compared to other existing multichain solutions, the AggLayer has a few unique characteristics:

• Fungible assets: Many interop solutions result in wrapped cross-chain assets. This isn’t unified liquidity, but further fragmentation. 
• No fee extraction: Chains (and users) aren’t taxed when joining the AggLayer—and ZK makes exits super easy, without the seven-day penalty of fraud proofs. 
• No imposition of chain architecture: There are no requirements or constitutions that chains must adhere to when they join; every chain is sovereign and completely customizable, but with security to protect the entire ecosystem from bad actors.
• One-time setup: When a chain joins the AggLayer, they get access to every other connected chain. 

So that’s the AggLayer from a high level. What does it look like on the ground?

Following a cross-chain transaction

If you want to dig into the weeds, check out the docs for the AggLayer to learn, for example, how a transaction works on a granular level.

At a high-level, it’s fairly easy to understand. Let’s unpack what bridgeAndCall() will enable users to do in one click:

1. transfer an asset from Chain A to Chain B; 
2. swap for a new asset; 
3. transfer the new asset from Chain B to Gaming Chain;
4. and mint a gaming NFT.

With bridgeAndCall(), it can happen in a single click.

Unpacking benefits for developers and users

Let’s bring it back to the beginning: a unified, aggregated environment is a game-changing synthesis for the next iteration of the Internet. The AggLayer enables people to access the Internet’s value in a unified ecosystem.

A few of the (many) benefits:

For developers:

• Building for unified users and liquidity: The AggLayer's unified bridge acts as a single point of entry for liquidity across connected chains. This eliminates the need for developers to bootstrap liquidity on individual chains, providing instant access to a large, aggregated ecosystem.
• Simplified cross-chain development: The bridgeAndCall() function streamlines cross-chain transactions, allowing developers to build complex, cross-chain logic. This simplifies the development process and enables the creation of truly interoperable applications.
• Expanded reach: Building on any one AggLayer-connected chain is the same as building on all of them. That means developers can maximize reach to a larger user base and enable seamless interactions with cross-chain dApps.

For users:

• Better UX: The AggLayer abstracts away complexities of transacting across connected chains. Think fungible assets, easy cross-chain experience that feels like interacting with a single blockchain.‍
• Enhanced security: The pessimistic proof ensures the safety and security of the unified bridge, ensuring no single chain can rug the entire ecosystem.

The Future is aggregated

The AggLayer is a paradigm shift, with a new aggregated thesis for unifying Web3. By providing a trustless and secure public good for cross-chain interactions, the AggLayer unlocks unparalleled benefits for developers and users.

As more chains join the AggLayer, the network effects will continue to grow, leading to increased liquidity, a wider range of applications, and even better user experience. Already, dozens of chains have announced plans to connect, including the Polygon Proof-of-Stake network (pending community consensus). And dozens more are in the works. Stay tuned.

An aggregated future is emerging faster than ever before—and bringing to fruition crypto’s full potential.

Tune into the blog and our social channels to keep up with updates about Polygon.

The future of Web3 is aggregated.

Website | Farcaster | X (Twitter) | Forum | Telegram | Discord | Instagram | LinkedIn | Polygon Knowledge Layer