Rollups
Layer Type, Scaling Solutions
Rollups are a Layer 2 scaling solution that bundle or “roll up” many transactions off-chain and then submit a single, compressed proof or summary of those transactions to a Layer 1 Protocol. This process drastically reduces congestion, lowers transaction costs, and leverages the security of the main chain. Rollups can be either optimistic (assuming transactions are valid unless challenged) or zero-knowledge (using cryptographic proofs for instant validation), making them a powerful tool for blockchain scalability.
Use Case: Platforms like Optimism and Arbitrum use rollups to enable thousands of transactions per second on Ethereum, offering fast, low-cost user experiences while inheriting Ethereum’s security.
Key Concepts:
- Layer One Protocol ÔÇö The base blockchain where rollup proofs are ultimately posted and finalized.
- Layer Two Protocol ÔÇö Networks built on Layer 1 to process transactions more efficiently, including rollups.
- Settlement Finality ÔÇö Ensures that once a rollup proof is posted to Layer 1, all bundled transactions are considered final.
- Throughput ÔÇö Rollups significantly increase the number of transactions per second compared to Layer 1 alone.
- Sidechains ÔÇö Alternative scaling methods to rollups, using independent chains linked to Layer 1.
Summary: Rollups are an essential component of blockchain scaling, allowing networks to process massive numbers of transactions with minimal cost, all while preserving the decentralization and security of the underlying Layer 1 protocol.
| Feature | Rollups | Traditional Layer 1 |
|---|---|---|
| Transaction Capacity | Thousands per second (batched) | Limited by block size and interval |
| Cost per Transaction | Very low (shared across batch) | Higher (each tx pays full fee) |
| Settlement | Finalizes on Layer 1 with proof | Directly on Layer 1 |
| Security | Inherits Layer 1 security | Native to Layer 1 |
| Examples | Optimism, Arbitrum, zkSync, Scroll | Ethereum, Bitcoin, XRP Ledger |