Ethereum’s next major upgrade, called Fusaka, a hybrid of “Fulu” (consensus) and “Osaka” (execution), will change the way the network manages data and fees without altering the core user experience.
Beneath the surface there is a policy statement: Ethereum’s main chain remains the center of final settlement and data availability, while daily activity continues to flow toward cheaper and faster rollups.
The open question of whether Fusaka will bring users back to Layer 1 already has its answer. It won’t. This will make layer 2 even harder to exit.
Inside Fusaka: resizing the plumbing and making the journey smoother
Fusaka’s technical backbone centers around data availability, sampling, and blob management, which is Ethereum’s approach to making Layer 2 publishing cheaper and more efficient. The main proposal, EIP-7594 (PeerDAS), allows nodes to sample only fragments of cumulative data, called “blobs,” instead of downloading the whole thing.
This frees up higher blob capacity and significantly reduces bandwidth costs for validators, a prerequisite for scaling L2 throughput.
Next comes EIP-7892, introducing “Blob Parameter-Only” forks, or BPOs, a mechanism for gradually increasing the number of blobs per block (for example, from 10 to 14, or from 15 to 21) without rewriting the protocol.
This effectively allows developers to adjust Ethereum’s data capacity without waiting for full upgrades. EIP-7918 sets a base price floor for blobs, ensuring that the auction price for data space does not collapse to near zero during low demand.
The rest of the offering focuses on user experience and security. EIP-7951 adds support for secp256r1, the cryptographic curve used in WebAuthn, making password logins on Ethereum wallets possible. EIP-7917 introduces deterministic proposator analysis, a small but significant change that helps pre-confirmation systems predict who will produce the next block, thereby enabling faster assurance of transactions.
Meanwhile, EIP-7825 caps transaction gas to avoid denial of service risks, and EIP-7935 adjusts default gas block targets to maintain validator stability.
These upgrades are already available on testnets like Holesky and Sepolia, with mainnet activation expected in early December.
Why Fusaka is important for fees and stacking economics
For users, Fusaka does not promise cheaper layer 1 gas. It is designed to reduce Layer 2 overhead. By allowing rollups to publish more data at a lower cost, the upgrade improves the profitability of networks like Arbitrum, Optimism, Base, and zkSync.
Internal modeling suggests that stacking fees could drop between 15% and 40% under typical conditions, or even as much as 60% if blob supply exceeds demand for an extended period of time. On the Ethereum mainnet, gas prices could remain roughly stable, although future adjustments to lock in gas targets could reduce them by another 10-20%.
However, password and nominator updates could make a difference in how Ethereum feels used. With support for WebAuthn, wallets can integrate biometric or device-based logins, removing the friction of seed phrases and passwords. With pre-confirmations enabled by predictable submitter schedules, users can expect near-instant confirmations for routine transactions, especially on rollups.
The net result is that Ethereum becomes smoother to use without bringing anyone back to L1. The rails become faster, but they are still pointed towards the rollup lane.
L1 as regulation, L2 as experience
Ethereum’s architecture is no longer a debate between monolithic and modular design: it is modular by choice. The purpose of Layer 1 is to serve as a basis for high-security settlement and data availability, while actual user activity is moved to Layer 2.
Fusaka reinforces this split. As blob capacity increases, L2s can handle higher throughput for games, social applications, and microtransactions that would not be profitable on the mainnet. Improvements to login and confirmation workflows make these L2 environments feel native and instant, erasing much of the UX gap that once favored L1.
Where can users still choose layer 1? In narrow cases, this involves large-value settlements, institution-wide transfers, or situations where block order accuracy is crucial, such as Miner Extractable Value (MEV) management or DeFi clearing. But these scenarios represent a small fraction of total on-chain activity. For the rest, L2 remains the natural home.
The Bigger Story: Ethereum as a Tiered Internet
Seen from above, Fusaka is less interested in gas optimization than in maturity. It gives Ethereum a scalable framework for scaling data capacity (BPO) without disruptive forks, and a UX layer that makes Web3 more like Web2.
However, its philosophy is clear: the network does not seek to centralize traffic on the main network. It involves building a highway system where rollups manage local traffic, and L1 serves as the courthouse where everything is ultimately notarized.
There is also a monetary layer to the story. Releasing data cheaply could bring a wave of new, low-value applications, such as social media, payments and gaming, back into the mix. Each of them still consumes ETH via blob fees, and along with EIP-7918’s floor fees, these fees contribute to the burning of ETH. Ethereum’s consumption rate could even increase if activity grows faster than fees decline, despite lower usage costs.
On the validator side, PeerDAS alleviates the bandwidth load but can create a new dependency on “supernodes” which store the entire blob data. This is a decentralization trade-off that the community will continue to debate: how to increase data availability without restricting participation.
The balance that Ethereum strikes here, between throughput, usability, and trust, reflects the broader direction of crypto infrastructure. L1s harden into secure foundations, while L2s absorb experimentation and scalability.
Takeaways
Fusaka is not aiming to regain the spotlight on the Ethereum mainnet. It’s the opposite: a deliberate decision to strengthen the foundations of a rollup-centric future.
The upgrade increases data capacity, stabilizes fees, and modernizes the wallet experience, but it does so in service of the upper layers. Ethereum’s L1 becomes more secure and smarter, while users continue to live with L2s that now run cheaper and faster than before.
When BPO1 and BPO2 roll out early next year, the real signals to watch will be blob utilization versus capacity, L2 fee compression, and wallet adoption of access keys. The result will define how frictionless Ethereum will feel in 2026, not by driving people back to the main chain, but by making the exit ramps almost invisible.
