What is a Rollup?

Rollup is a layer-2 solution developed to increase the scalability of blockchain networks. To reduce the transaction load on the main blockchain, for example Ethereum, it processes some transactions off-chain and records them in batches on the mainchain. This scaling solution aggregates a large number of transactions and sends them to the mainchain as a compressed data set. This reduces transaction costs, lowers gas fees, mitigates network congestion, and increases transaction speed while continuing to benefit from the security of the mainchain.

Rollups in the blockchain ecosystem provide significant advantages, especially for projects with high transaction volumes. Users can perform faster, cheaper, and scalable transactions by utilizing this technology. With these features, scalability solutions have started to be widely used in popular blockchain networks like Ethereum.

What are the types of Rollups?

The solutions in question are layer-2 solutions used to increase the scalability of blockchain networks and are primarily divided into two main types: Optimistic Rollup and ZK-Rollup. Below, these varieties are explained in two paragraphs:

( 1 Optimistic Rollup

Optimistic Rollup is a type of solution that assumes the correctness of transactions and only verifies them in the case of a challenge ). Transactions are processed off-chain and recorded on the mainchain as a compressed dataset. If a transaction is faulty, it is detected and corrected within a specific challenge period, typically 7 days. This method provides low computational costs and high transaction volumes, making it particularly popular in applications such as DeFi and NFTs. For example, Arbitrum and Optimism are leading protocols that use these Optimistic solutions. However, due to the challenge period, withdrawal transactions may be delayed, which can impact user experience.

Such solutions operate on the assumption of the accuracy of off-chain transactions. That is, transactions are aggregated off-chain and are assumed to be correct when sent to the chain. However, in the case of an error, users can appeal within a certain period. Thus, security and decentralization are maintained.

( 2 ZK-Rollup )Zero-Knowledge Rollup(

ZK-Rollup is a type of solution that mathematically guarantees the correctness of transactions using zero-knowledge proofs ). After transactions are processed off-chain, a cryptographic proof ###, for example, ZK-SNARK or ZK-STARK(, is sent to the mainchain, providing high security. ZK-Rollups stand out for their fast transaction finality and low dispute times, but the proof generation process requires more computational power, which can increase costs. Protocols like StarkNet and zkSync utilize this technology. ZK-Rollups are particularly suitable for applications that require privacy and high security, but the complexity makes the development process more challenging.

These types of measurable solutions process transactions off-chain and only add a cryptographic proof )zero-knowledge proof( to the chain. This proof verifies that the transactions are valid. ZK-Rollups typically offer faster confirmation times and greater privacy.

This article does not contain investment advice or recommendations. Every investment and trading activity carries risks, and readers should conduct their own research when making decisions.