Shared DA layers vs Dedicated DA per rollup

Shared DA layers, like Celestia, EigenDA, or Avail, excel at cost efficiency and rapid deployment because they amortize security and data storage costs across hundreds of rollups. For example, posting data to Celestia can cost ~$0.01 per MB, orders of magnitude cheaper than Ethereum calldata, enabling high-throughput chains like Arbitrum Nova to scale affordably. This model provides a standardized, battle-tested foundation, reducing time-to-market and operational overhead for new rollups.

Dedicated DA per rollup, where each rollup posts its data directly to a base layer like Ethereum, takes a different approach by maximizing security and ecosystem integration. This results in the trade-off of higher, more volatile costs for the strongest possible security guarantees. Chains like Arbitrum One and Optimism pay Ethereum's L1 gas fees for data, which can spike, but they inherit Ethereum's unparalleled validator set and censorship resistance, a non-negotiable for high-value DeFi protocols securing billions in TVL.

The key trade-off: If your priority is minimizing transaction costs, achieving maximum throughput, and launching quickly, choose a Shared DA layer. If you prioritize absolute security, deep composability with Ethereum's DeFi ecosystem, and are building a high-value application, choose a Dedicated DA on Ethereum. Your decision ultimately hinges on whether you value economic scalability or maximal security inheritance.

Shared DA layers like Celestia, EigenDA, and Avail excel at providing low-cost, high-throughput data availability by amortizing security and infrastructure costs across hundreds of rollups. This results in dramatically lower transaction fees for end-users. For example, a rollup using EigenDA can achieve data availability for under $0.001 per transaction, a critical metric for high-frequency applications. This model fosters a modular ecosystem where projects like Arbitrum Orbit and Optimism's OP Stack can easily plug into a shared security base.

Dedicated DA per rollup, where a rollup posts its data directly to a base layer like Ethereum, takes a different approach by prioritizing maximal security and sovereignty. This results in the trade-off of significantly higher costs—Ethereum blob fees can be 10-100x more expensive than a shared alternative—but provides the strongest possible cryptographic guarantees and direct alignment with the most battle-tested settlement layer. This is the path chosen by protocols like zkSync Era and Base, which value Ethereum's consensus above all else.

The key trade-off is cost vs. security sovereignty. If your priority is minimizing user transaction fees, achieving hyper-scalability, and operating within a modular stack, choose a shared DA layer like Celestia. If your priority is maximizing security by inheriting Ethereum's full consensus, maintaining direct composability with the L1, and accepting higher operational costs for that guarantee, choose dedicated DA on Ethereum. For teams building consumer dApps or gaming protocols, shared DA is often the pragmatic choice. For protocols managing billions in TVL or requiring the strongest possible trust assumptions, dedicated DA remains the gold standard.