Ethereum's scalability journey has been shaped by the need to address the "blockchain trilemma," which posits that security, decentralization, and scalability cannot all be achieved simultaneously within a Layer 1 (L1) network.
What to Know About Ethereum Rollups?
Ethereum has historically prioritized security and decentralization, leaving scalability as a challenge. With transaction fees rising and processing times slowing as user demand grows, Layer 2 (L2) solutions, particularly rollups, have emerged as critical tools to overcome these limitations.
Rollups scale Ethereum by moving computation off the main chain, bundling transactions into compressed batches, and submitting them to L1 for verification. This approach enables faster and cheaper transactions while preserving Ethereum's security and decentralization.
Rollups have become central to Ethereum's roadmap since 2020, making use cases like on-chain gaming and high-speed decentralized finance (DeFi) viable. Among rollup types, zk-rollups have gained dominance due to their efficiency and security, leveraging zero-knowledge proofs for validation. Projects like zkSync Era and Linea are leading in adoption, offering low fees and high throughput.
Despite their success, rollups face challenges such as fragmentation of state and liquidity across different rollup networks, limiting user experience and developer adoption. Additionally, many rollups still rely on centralized components like sequencers for transaction ordering, which introduces risks of censorship.
Ethereum's roadmap aims to evolve rollups toward full decentralization by removing these "training wheels" - centralized safeguards - and enabling trustless systems for transaction sequencing and proof generation.
For Ethereum users, rollups are essential to reducing costs and improving transaction speeds. However, they should be aware of the trade-offs between different rollup architectures - such as zk-rollups versus optimistic rollups - and the ongoing evolution toward decentralization. As rollups mature, they will play an increasingly critical role in shaping Ethereum's scalability and user experience.
Key Features of Based Rollups:
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Decentralized Sequencing: Instead of using a designated sequencer or centralized entity, transaction ordering is handled by Ethereum’s own validators. This approach significantly reduces risks of censorship and transaction manipulation, ensuring fair and transparent processing.
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Seamless L1 Integration: Ethereum’s L1 infrastructure handles consensus, data publication, and settlement, while execution happens on the rollup network. This design inherits Ethereum’s security and decentralization properties without adding new layers of trust assumptions.
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Simplified Architecture: By removing the need for centralized sequencers, based rollups create a leaner and more Ethereum-aligned transaction processing model. This simplification also reduces reliance on external governance structures, making them more robust in the long term.
Advantages of Based Rollups:
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Stronger security and decentralization by leveraging Ethereum validators.
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Reduced dependency on external governance and infrastructure providers.
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A streamlined system that stays true to Ethereum’s original ethos.
Challenges and Considerations:
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Throughput Limitations: Since Ethereum’s L1 block times are longer (approximately 12 seconds), transaction finality may be slower compared to rollups with dedicated sequencers.
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Pre-Confirmation Innovations: To mitigate latency issues, developers are exploring pre-confirmation techniques that allow transactions to be tentatively confirmed before full inclusion in L1 blocks.
Key Features of Native Rollups:
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Direct Ethereum Validation: Native rollups eliminate the need for additional proof systems by leveraging Ethereum’s built-in transaction validation rules. This ensures that state transitions are verified within Ethereum itself, removing complexity from rollup implementations.
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Automatic Upgrades: Since native rollups operate within Ethereum’s core infrastructure, they automatically inherit protocol upgrades. This avoids governance bottlenecks that often affect traditional rollups requiring manual security council approvals.
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Simplified Security Model: By posting transaction data directly to Ethereum and utilizing its validation mechanisms, native rollups reduce the need for independent security models, making the system more unified and easier to maintain.
Advantages of Native Rollups:
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Greater Trustlessness: Transactions are verified directly by Ethereum, ensuring alignment with its security guarantees.
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Lower Maintenance Overhead: Rollup teams benefit from Ethereum’s security and consensus mechanisms, reducing operational complexity.
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Better Ecosystem Interoperability: Since validation happens at the Ethereum protocol level, native rollups enable more seamless interactions between different L2 solutions.
Challenges and Considerations:
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Protocol Modifications Required: Implementing the EXECUTE precompile necessitates changes to Ethereum’s protocol, requiring coordination through hard forks and ecosystem-wide upgrades.
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MEV-Based Centralization Risks: Miner Extractable Value (MEV) could introduce competition for transaction ordering, potentially centralizing aspects of the rollup execution process. Mechanisms to mitigate these risks are being explored.
Choosing Between Based and Native Rollups
Ethereum's Layer 2 ecosystem continues to evolve, and both based and native rollups offer innovative approaches to scaling while maintaining security and decentralization. Each model presents distinct advantages and trade-offs, making the choice between them dependent on the priorities of developers, users, and the broader Ethereum community.
Based rollups integrate with Ethereum’s existing validator-based sequencing model, reinforcing decentralization by leveraging Layer 1 validators to order transactions. This reduces reliance on centralized sequencers but may introduce latency due to Ethereum’s block times. In contrast, native rollups are more deeply embedded within Ethereum’s core protocol, eliminating the need for separate sequencing mechanisms and proof systems. While this integration streamlines transaction validation, it requires significant protocol upgrades, potentially through hard forks.
Security remains a strong point for both approaches, as they inherit Ethereum’s robust Layer 1 security model. However, native rollups take this a step further by using Ethereum’s built-in validation mechanisms, removing the need for fraud proofs or zero-knowledge proofs. Governance is another key difference - based rollups align with Ethereum’s economic model but still require some independent governance, while native rollups automatically adopt Ethereum upgrades, reducing governance overhead.
Ultimately, the adoption of based or native rollups will depend on Ethereum’s long-term vision for scalability. While based rollups provide an immediate path forward with minimal protocol changes, native rollups offer a more integrated, long-term solution for efficiency and scalability. As rollup technology matures, Ethereum’s Layer 2 landscape will continue to improve, bringing faster, cheaper, and more secure transactions to users worldwide.