EigenDA

EigenDA is a data availability (DA) service built as a cryptoeconomic security layer on top of Ethereum, leveraging restaking via EigenLayer. It allows rollups (like Optimistic and ZK Rollups) to publish their transaction data to a network of operators instead of directly to Ethereum's expensive calldata, significantly reducing transaction costs while inheriting Ethereum's security. This is achieved by using a technology called data availability sampling (DAS), where light clients can verify that data is available without downloading it all.

The system's security is derived from Ethereum validators who opt-in to restake their ETH and run EigenDA software, becoming operators. These operators form a committee that collectively attests to the availability of data blobs. If they act maliciously by withholding data, their restaked ETH is slashed. This model, known as restaking, allows EigenDA to bootstrap a secure network without launching a new, fragile token, creating what is termed intersubjective forking to resolve disputes over data availability.

For rollup developers, integrating EigenDA typically involves modifying their sequencer to post data blobs to EigenDA nodes instead of Ethereum L1. The associated data availability certificates or attestations are then posted back to a smart contract on Ethereum, providing a verifiable record. This architecture enables modular blockchain design, where execution, settlement, consensus, and data availability are separated into specialized layers. EigenDA is a core component of the EigenLayer ecosystem, which aims to provide a marketplace for decentralized trust.

Key performance metrics for EigenDA include throughput, measured in megabytes per second (MB/s) of data, and cost, which is a fraction of the equivalent cost to publish on Ethereum L1. Its design prioritizes high scalability and low latency for data posting, making it suitable for high-frequency applications. As a DA layer, it does not execute transactions or provide consensus for settlement; it solely guarantees that the data necessary to reconstruct a rollup's state is published and accessible.

The primary use case is scaling Ethereum Layer 2 solutions. By offloading the most expensive component of a rollup's operation—data publication—EigenDA can reduce user fees by orders of magnitude. It also enables new design spaces for sovereign rollups and validiums, which trade off some security guarantees for even greater scalability. Its development is closely tied to proto-danksharding (EIP-4844) on Ethereum, which introduced blob transactions, a native data format that EigenDA and other DA layers utilize.

EigenDA operates as a cryptoeconomic security marketplace where operators who have restaked their ETH via EigenLayer provide attestations to the availability of data blobs. These operators run EigenDA nodes that sign cryptographic attestations, forming a Data Availability Committee (DAC). When a rollup or application submits data, the committee collectively attests to its availability, generating a Data Availability Certificate. This certificate, secured by the slashing conditions of the restaked ETH, is then posted back to the originating rollup's smart contract on Ethereum L1, proving the data is retrievable.

The system's architecture separates consensus from data availability. EigenDA does not run its own consensus for transaction ordering; instead, it relies on the underlying Ethereum consensus for the canonical ordering of its attestations. This design allows it to focus exclusively on scalable data attestation. Through techniques like KZG polynomial commitments and erasure coding, EigenDA ensures data can be reconstructed even if some committee members are offline or malicious. The dispersal process involves splitting the data blob into chunks and distributing them across the operator network.

Performance is achieved through horizontal scaling via quorum-based security. A rollup can choose its security parameters by specifying the number and type of operators in its committee. This creates a trade-off between cost, throughput, and security. EigenDA's throughput—measured in megabytes per second (MB/s)—scales with the number of active operators, as the work of attesting to data is parallelized across the decentralized network. This model contrasts with monolithic blockchains where throughput is limited by a single, global consensus mechanism.

The finality of data availability is soft-confirmed upon receiving the requisite threshold of operator signatures and is economically finalized once the attestation transaction is included in an Ethereum block. This dual-layer finality provides fast guarantees for rollups while inheriting Ethereum's robust settlement security. Fault proofs and slashing mechanisms penalize operators for equivocation or for failing to store and serve their assigned data chunks, ensuring the cryptoeconomic security of the entire system.

EigenDA is a data availability (DA) service that provides a cryptoeconomic security model derived from EigenLayer's restaking mechanism. Its core security guarantee is that data blobs posted by rollups are available for download by any network participant, enforced by a decentralized set of operators who have staked (or, more precisely, restaked) ETH. If an operator withholds data or attests to its availability incorrectly, they are subject to slashing penalties on their restaked capital. This model allows EigenDA to inherit a significant portion of Ethereum's economic security without requiring a new, independent token or validator set.

The security model operates through a dual-attestation system. First, a Disperser node receives data from a rollup sequencer, erasure codes it into chunks, and distributes these chunks to the operator set. Operators then cryptographically attest—by signing a message—that they have received and stored their assigned data chunks. These attestations are aggregated into a single proof and posted to the EigenDA management contract on Ethereum. For a user or a rollup node to be convinced the data is available, they must only verify this aggregated signature against the known operator set and then be able to successfully retrieve a sufficient number of chunks from the network to reconstruct the original data.

A critical component is the Data Availability Committee (DAC), which in EigenDA's case is not a small, permissioned set but the entire decentralized operator set. The security scales with the total amount of restaked ETH delegated to these operators. The system employs proof-of-custody schemes, where operators must periodically prove they are physically storing the data assigned to them, not just attesting to it. Failure to provide a valid proof-of-custody can also trigger slashing. This combination of cryptographic attestations, economic penalties, and direct proofs of storage creates a robust deterrent against data withholding attacks.

EigenDA's security is actively verified by a role called the Watchtower. Watchtowers are permissionless entities that continuously monitor the network, challenge incorrect operator attestations, and can initiate slashing proposals. This creates a verification game similar to optimistic rollups, where security relies on the presence of at least one honest verifier. The final security backstop is Ethereum itself: all slashing proposals and dispute resolutions are ultimately settled on the Ethereum L1, ensuring the enforcement of the system's rules is as secure as the underlying blockchain.