Why Ethereum's Data Sharding is Still the Endgame for ZKRs

Every external DA layer forces a rollup to sacrifice one core property for another. This fragmentation creates systemic risk and liquidity silos.

• Security vs. Cost: Celestia offers low-cost DA but inherits its own consensus security, not Ethereum's.
• Decentralization vs. Speed: EigenDA provides high throughput but relies on a permissioned set of operators, creating centralization vectors.
• Composability vs. Sovereignty: Using a separate chain for DA (like Avail) breaks atomic composability with Ethereum L1, the ecosystem's liquidity hub.

EIP-4844 introduces blob-carrying transactions, a dedicated data channel that decouples DA cost from execution gas. This is the critical stepping stone.

• Cost Plummets: Blob data is cheap and ephemeral, reducing rollup costs by ~10-100x versus calldata.
• Security Preserved: Data is posted to and validated by all Ethereum consensus nodes, inheriting full L1 security.
• Ecosystem Unification: Provides a canonical, shared DA layer for all L2s, restoring atomic composability and simplifying developer UX.

The final stage scales blob capacity to ~1.3 MB per slot via data availability sampling (DAS). This is where Ethereum becomes the universal DA settlement layer.

• Horizontal Scale: 64 data shards provide effectively unlimited, low-cost bandwidth for thousands of rollups.
• Light Client Verifiability: DAS allows nodes to verify availability with minimal data, preserving decentralization.
• ZK-Native Future: The massive, secure data pipeline is perfectly suited for ZK-rollups like Starknet, zkSync, and Scroll to achieve finality in minutes, not hours.

Hybrid models like StarkEx Volitions and zkPorter are the pragmatic bridge, letting apps choose between full security (ZK-rollup) and lower cost (Validium). This flexibility is temporary.

• Optionality Today: Apps can use Ethereum for consensus and an external DA (e.g., Celestia) for data, cutting costs by another ~10x.
• Convergence Tomorrow: As blobspace becomes cheaper, the economic incentive to exit to an external DA vanishes, naturally unifying the stack on Ethereum.
• Proves the Thesis: Their existence validates the demand for cheap DA, but their optionality highlights the current fragmentation that full danksharding resolves.

Blob space is a separate, scarce resource. During high demand, ZK rollups like zkSync, Starknet, and Scroll will bid against each other, creating unpredictable data posting costs. This directly undermines the promise of stable, ultra-low fees for end-users.\n- Cost Volatility: Blob gas spikes could make L2s temporarily more expensive than alt-L1s.\n- Economic Inefficiency: ZKRs must over-provision capital or risk delayed proofs.

Danksharding assumes ZKRs will eagerly use Ethereum for data availability (DA). Competing DA layers like Celestia, EigenDA, and Avail offer cheaper, dedicated bandwidth today. If major rollups fragment across these systems, Ethereum loses its cohesive security model and network effects.\n- Security Splintering: Users must trust multiple DA security assumptions.\n- Liquidity Fragmentation: Cross-rollup composability breaks without a shared DA base.

Danksharding solves data, not computation. Generating validity proofs remains a highly centralized, capital-intensive operation. A handful of prover operators (e.g., Ulvetanna, Ingonyama) could control the sequencing and finality of major ZK rollups, creating a new layer of trust.\n- Hardware Oligopoly: Access to top-tier GPU/ASIC farms is limited.\n- Sequencer-Prover Coupling: Dominant players could extract MEV or censor transactions.

Danksharding's complexity is buried in the consensus layer (CL). Execution clients like Geth still handle ~85% of nodes. If CL upgrades outpace EL client diversity, we reinforce a single implementation's dominance. A critical bug in Geth could still halt the chain, making the entire scaling edifice brittle.\n- Single Point of Failure: The "Diversity-Proof" goal remains unmet.\n- Complexity Burden: Fewer teams can audit the full, integrated post-Danksharding stack.

With data sharded into blobs, a native cross-rollup message becomes a cross-shard communication problem. Protocols like LayerZero and Axelar abstract this, but they add latency and trust layers. Fast, trust-minimized bridges (e.g., Across, Chainlink CCIP) still require complex fraud-proof windows or oracle committees, negating the "single atomic chain" user experience.\n- Latency Penalty: Secure cross-rollup finality moves from minutes to hours.\n- Trust Assumptions: Users delegate security to external bridge protocols.

Blobs are large, public data commitments. Regulators could pressure node operators or infrastructure providers (e.g., AWS, Google Cloud) to censor or delist specific blobs, effectively freezing rollup state. While validity proofs ensure correctness, they cannot guarantee liveness if the data is unavailable. This attacks the core premise of credibly neutral scaling.\n- Infrastructure Censorship: Centralized RPCs and block builders become attack points.\n- Legal Uncertainty: Is posting a blob a regulated "data transmission"?

Today, ZK-Rollups like zkSync and StarkNet post all transaction data to Ethereum L1, paying ~80% of their costs in calldata fees. This creates a hard economic limit on scaling.

• Cost: Posting 1MB of data costs ~$10,000 at 100 gwei.
• Bottleneck: Throughput is gated by L1 block space, not ZK-proof generation speed.
• Risk: Without cheap DA, ZKR economics fail, pushing users to centralized alternatives.

Ethereum's Proto-Danksharding (EIP-4844) and full Danksharding create a dedicated, low-cost data layer (blobs) for all rollups. This is a neutral, credibly neutral substrate.

• Scale: Targets ~1.3 MB/s with EIP-4844, scaling to ~1.3 GB/s long-term.
• Cost: Blob fees are ~100x cheaper than calldata, decoupling ZKR cost from L1 congestion.
• Network Effect: Every ZK-Rollup (zkSync, Scroll, Polygon zkEVM) and intent-based system (UniswapX, Across) can share this secure base layer.

Projects like Celestia, Avail, and EigenDA offer cheaper DA now, but fragment security and liquidity. This creates long-term systemic risk.

• Security: Alt-DA layers have ~$1B in stake vs. Ethereum's ~$100B+ economic security.
• Fragmentation: Isolated DA breaks composability, turning L2s into isolated islands.
• Winner-Take-All: Data availability is a natural monopoly; the most secure and integrated network (Ethereum) will dominate.

The real value accrual is at the base data availability layer, not individual ZK-Rollup implementations. Ethereum is becoming the global settlement and data layer.

• Moats: Ethereum's DA moat is its decentralized validator set and unmatched economic security.
• Capture: Value flows to ETH stakers and the base asset securing the data.
• Action: For builders, integrate blobs. For investors, the asymmetric bet is on ETH's dominance as the canonical data root.