Rollups: Streamlining Blockchain Scalability¶
Rollups are designed to enhance blockchain scalability by simplifying transaction processing. The key concept involves managing multiple transactions off-chain, consolidating them into a single batch, and then submitting this batch as a unified action to the main blockchain.
The result is a notable reduction in transaction processing times and gas fees, making rollups an attractive solution for improving efficiency on platforms like Ethereum.
ZK Rollups Vs Optimistic Rollups¶
Two primary types of rollups are utilized: ZK Rollups (Zero-Knowledge Rollups) and Optimistic Rollups.
ZK Rollups¶
In ZK Rollups, the batch of transactions undergoes thorough verification for correctness on the main network. Successful verification leads to the batch being treated as final, similar to a standard transaction. This verification relies on cryptographic validity proofs, such as zero-knowledge proofs. Notable examples include zkSync, which employs a zkSNARK for this process.
Optimistic Rollups¶
Optimistic Rollups take a distinct approach by lacking a direct mechanism to prove the validity of off-chain transactions. Operating on the assumption that off-chain transactions are valid unless proven otherwise, these rollups rely on fraud-proof systems. Challenges to the submitted state trigger the need to demonstrate the validity of the questioned state and transactions. Examples include Optimism and Arbitrum.