tl;dr: Over the past couple of days, some L2s observed that their deployments on Sepolia did not work correctly anymore. This is because of EIP-7594 which modifications the format for proofs. In anticipation of Fusaka, we urge all blob originators to replace their software program to create Cell Proofs as an alternative of blob proofs.
Background
One underdiscussed side of EIP-7549 (PeerDAS) is that it modifications the format for proofs from blob proofs to cell proofs. This enables for downloading a particular a part of the blob as an alternative of the entire blob for information availability sampling.
This variation may break consumer purposes that ship blob transactions. Already signed transactions are nonetheless legitimate although, they simply must recompute the cell proofs. Some purchasers (most notably go-ethereum) will do that by way of the RPC on eth_sendTransaction and eth_sendRawTransaction (1). This conversion from blob proofs to cell proofs takes about one second, so we encourage blob transaction originators to maneuver to cell proofs with a view to scale back overhead on the RPC stage.
Transactions which might be within the txpool on the time of the fork shall be dropped by some implementations, whereas different implementations will convert them to cell proofs. So it might be prudent to resend your transactions with cell proofs shortly after the fork, if they don’t seem to be being included by the chain. Some implementations permit for the distribution of blob proof transactions up to some minutes after the exhausting fork on the networking layer for stability functions.
Actionable modifications
If you’re a blob transaction originator (e.g. an L2), you must replace your transaction sending code to create cell proofs.
All main shopper libraries expose performance to create these proofs by way of ComputeCellsAndKZGProofs() which is on the market in all main languages (2). Utilization examples will also be present in all main languages within the shopper libraries (3).
Outlook
We are going to attempt to talk these modifications that impression customers extra clearly by way of the Ethereum weblog going ahead and attempt to do extra neighborhood outreach to forestall customers of Ethereum from feeling blindsided by modifications within the protocol.
We additionally encourage L2s and different entities that closely rely on the Ethereum roadmap to comply with the ACD course of and to have interaction extra instantly with the neighborhood. We might additionally prefer to encourage groups to deploy their contracts and take a look at infrastructure on the devnets shortly earlier than we transfer to the primary testnets.
One other useful gizmo for conserving your modifications updated is to make use of the Ethereum bundle supplied by Kurtosis which can be utilized to create native networks with the newest specs (4).
Whereas it’s unlucky that blob originators realized this late within the exhausting fork course of, it additionally reveals that the testnet course of works very properly and these points are caught lengthy earlier than they might ever seem on mainnet.
(1): go-ethereum will solely do the conversion on eth_sendRawTransaction from present grasp and v1.16.5 onwards (2): see https://github.com/search?q=repopercent3Aethereumpercent2Fc-kzg-4844percent20ComputeCellsAndKZGProofs&kind=code (3) Instance for go-ethereum: https://github.com/ethereum/go-ethereum/blob/7c107c2691fa66a1da60e2b95f5946c3a3921b00/crypto/kzg4844/kzg4844_test.go#L194 (4) Ethereum bundle for kurtosis: https://github.com/ethpandaops/ethereum-package
