Data availability (DA) is the process by which Layer N makes available the entire history of transaction data it receives to network nodes who can then use this history to reconstruct state transitions, and verify that the state on Layer N is indeed correct and legitimate. In the case where a state transition is invalid, a node can use the transaction data to construct a fraud proof used to roll back the chain state and to slash the validator that submitted the fraudulent state update.
Having a highly efficient data availability architecture is extremely important in building a secure and performant blockchain. Layer N's modular architecture allows it to uniquely leverage industry-leading high-bandwidth data availability networks.
Layer N's DA of choice is EigenDA.
Eigen DA ↗ (opens in a new tab) is a hyperscaled DA layer providing high DA rates and low costs utilizing EigenLayer restaking and cutting edge ideas in DA developed in the Ethereum community, including Danksharding. Eigen Layer re-purposes Ethereum stakers, thus also enabling high security guarantees.