Hybrid rollups: The silver bullet for scalability and security on Ethereum

Graphic designers have an old saying: “Your project can be fast, cheap or good — pick two.” It’s a classic trilemma. Rushing to create something might mean it’ll be delivered quickly, and therefore less expensive. Then again, the end product could be disappointing. If customers go the “cheap and good” route instead, they’re willing to wait a while — it’s going to take time, and projects that pay better will be prioritized.

For years, there’s also been a lot of talk in the blockchain world about a trilemma in terms of decentralization, security and scalability: decentralized networks can only provide two of the three benefits at any given time.

Experts argue that scalability requires a trade-off with security. In this case, a network can handle more transactions, but the risk of an exploit increases.

But this doesn’t necessarily have to be the case. Right now, developers are working on layer-2 solutions to help increase the capacity of the Ethereum network following its ambitious upgrade to a proof-of-stake (PoS) consensus mechanism.

Introducing hybrid rollups

There is one solution allowing developers to build decentralized applications (DApps) — and this is hybrid rollups, which combine two different architectures and can cope with high levels of traffic, making Ethereum a compelling blockchain for building the next generation of the internet.

The first element involves optimistic rollups, where transactions are processed off-chain to reduce network congestion and cut gas costs — another key hurdle on the road to adoption. According to the developers, this has the potential to increase scalability by up to 100 times, while records are then updated on the mainnet.

The second ingredient is zero-knowledge rollups, which provide security and fast finality. This technology can reduce the time it takes to complete transactions from seven days to as little as four hours — all without the need for additional data processing. In the real world, this is the equivalent of packing more clothes in a suitcase. Even better, trustless cryptographic mechanisms ensure the blockchain is resilient against exploits.

Bringing both types of rollups together makes sense, as each of these architectures has its limitations. A hybrid approach takes advantage of both, while providing the best possible experience for users and developers alike.

Other advantages

Hybrid rollups are the brainchild of Metis, an Ethereum-based layer-2 solution provider. According to the project, the benefits don’t end there.

Source: Metis

Full compatibility with the Ethereum Virtual Machine (EVM) means developers get an easy-to-code-in blockchain. There are also benefits for users, especially considering they have the freedom to withdraw funds from layer-2 protocols without delay.

While there have long been concerns about the creeping tide of centralization, Metis says its model encourages decentralization, with transactions processed in parallel.

The team behind Metis shared:

“One of our goals is to solve the scalability trilemma by combining the transcendent scalability of optimistic rollups with the security and fast finality of zero-knowledge rollups. Thus, we create a developer-friendly layer-2 allowing Ethereum developers to deploy all kinds of decentralized applications. The deeper Web3 dives into DeFi, the deeper builders must go to enable the highest security standards possible — and zero-knowledge proofs will do precisely that.”

Metis says it’s determined to increase the potential use cases for blockchain technology, and reducing finality times is key. Optimistic rollups derive their name from the fact that it’s assumed that all transactions are valid, with a seven-day window in place to prevent fraud. Meanwhile, zero-knowledge proofs significantly reduce this time and could be the silver bullet for enticing businesses to join the Web3 revolution.

Why this technology is needed

Scalability concerns on the Ethereum network have been long documented and affect gas fees. Vitalik Buterin himself has admitted that costs need to come down for crypto transactions to be economically viable for consumers in emerging economies.

Innovation is key to bridging the gap between scalability and security and delivering long-term growth for this thriving sector. A robust blockchain that can process transactions quickly and cheaply has the potential to transform businesses around the world and‌ lead to the creation of a new wave of decentralized autonomous companies (DACs), where a corporation can be self-governed and controlled by shareholders through democratic votes.

Metis’ argument is crystal clear: The Ethereum blockchain can be fast, cheap and good, and hybrid rollups — which are being built right now and open-sourced for the benefit of all crypto users — are set to make this a reality.