Rob Behnke
January 22nd, 2024
One of the biggest challenges faced by blockchain technology is scalability. Traditional Layer-1 blockchains have a maximum number of transactions that they can fit into a block, limiting their potential throughput. This limited throughput creates significant challenges for blockchain adoption and growth since the more a blockchain is used, the slower it runs.
Rollups were invented as a means of scaling the blockchain. To reduce the consumption of an L1 blockchain’s limited space, rollups move transactions off-chain. These transactions are batched together into a mass state update that is recorded to the L1 chain.
Based on the rollup architecture (Optimistic vs. zkRollup), the accuracy of these updates is verified by either incentivizing challenges to incorrect updates or by using zero-knowledge proofs. After a certain point, rollup transactions are finalized on-chain, enabling the recipient to use their new assets.
However, rollups have their own throughput limitations, and cross-rollup transactions are currently a difficult challenge. Hyperchains and Superchains are related solutions proposed to enable greater blockchain scalability. Both solutions offer horizontal scalability and trustless cross-rollup transfers, but they differ in their underlying infrastructure.
Hyperchains are a concept developed by zkSync Era to improve blockchain scalability. With Hyperchains, multiple instances of a zkEVM operate in parallel, enabling greater blockchain scalability. These different instances are linked to one another using Hyperbridges, enabling swaps and communication between them. These Hyperbridges are shown as the orange arrows in the image below (Source: zkSync Era) and are implemented by deploying Layer-3 smart contracts within each Hyperchain.
All of these Hyperchains will share a bridge smart contract on the Layer-1 blockchain (Ethereum, etc.). This ensures Layer-1 finality of transactions on the blockchain and enables assets to be easily and trustlessly minted and burned to transfer them between the various hyperchains.
The concept of the Superchain was created by Optimism. Optimism developed an open-source toolkit — called the OP Stack — for building Layer 2 Optimistic rollups that run on the Ethereum network. Using this toolkit, it is easier for developers to create, customize, and deploy these rollups to meet their needs.
The OP Stack toolkit is a key component of Optimism’s Superchain scaling solution. Optimism’s Superchain consists of all Layer 2 rollups built using OP Stack. These rollups will share the same bridges, communication layer, and security, similar to how Hyperchains have the same Layer 1 bridge contract. As a result, these parallel rollups can easily communicate, making message passing and cross-rollup transfers easier and more secure than with independent rollups using different underlying architectures.
Hyperchains and superchains are related concepts developed by different organizations. Hyperchains are related to zkSync Era, while the Superchain was developed by Optimism.
At a high level, the main difference between Hyperchains and the Superchain is the rollup architecture that they use:
Hyperchains: zkSync’s Hyperchains implement zkRollups, which use zero-knowledge proofs to prove the correctness of their state updates. This offers instant finality on L1 since anyone can evaluate the provided proof and verify that a set of bundled transactions creates the indicated state update.
Superchain: Optimism’s Superchain uses Optimistic rollups. Optimistic rollups assume that a state update is correct unless a challenge is submitted within the challenge period. As a result, they do not offer instant finality on L1, and assets are locked until the challenge period expires for a particular bundle.
Beyond these high-level differences, Hyperchains and Superchain are similar systems with similar goals. In both cases, the intent is to enable horizontal scalability of rollups by building with a shared architecture and underlying infrastructure.
Hyperchains and the Superchain are designed to solve the same problem and use similar approaches. This means that they both provide various benefits to the blockchain and its users, including:
Horizontal Scalability: Both Hyperchains and the Superchain offer the potential to deploy multiple rollups in parallel. This dramatically increases the scalability of the blockchain since each rollup can independently process transactions and write them to the blockchain as a more space-efficient bundle.
Rollup Integration: Cross-rollup swaps and communication are currently a major challenge and limitation of rollup architectures. Both of these solutions implement shared infrastructure that can support efficient, secure swaps across rollups.
Standardization: Both Hyperchains and the Superchain offer tools for developers to deploy their own rollups. This creates a greater level of standardization that can enhance integration and security.
Security and Trust: Within each ecosystem, parallel rollups share the same security infrastructure and record transactions to an L1 blockchain. This both helps to ensure the security of each rollup and creates trust between them, enabling more efficient cross-rollup swaps.
Beyond these shared benefits, each implementation also has its unique pros and cons. For example, the use of zkRollups in Hyperchains means that rollup transactions have instant finality on L1. This fact, combined with the greater capacity created by running many rollups in parallel, creates the capacity for extremely fast transactions within the rollup ecosystem.
Scalability is one of the biggest challenges facing blockchains today. Layer 1 blockchains have limited scalability, and existing rollups have their own challenges, including the complexity of moving assets between rollups across bridges.
Hyperchains and Superchain offer a solution to this challenge. By creating multiple parallel rollups with a shared underlying infrastructure, they both offer the potential to dramatically improve rollups’ horizontal scalability while also enabling trustless and painless transfers of assets between these parallel rollups.
While Hyperchains and Superchain offer strong security, building on them is not without risk. Even if the EVM or zkEVM used by a rollup is secure, smart contracts deployed within it may contain vulnerabilities that leave it vulnerable to exploitation. Additionally, some platforms may have their security risks, such as Optimistic rollups’ reliance on challenges to ensure that state updates are valid.
When building in any smart contract environment, a security audit is an essential part of ensuring that smart contracts are not vulnerable to attack. For more information about securing your smart contracts with Halborn, get in touch.