Ethereum's Fusaka upgrade went live on December 3, bringing significant improvements to Layer 2 data costs, network capacity, and core infrastructure. This upgrade signals a notable shift in how Ethereum anticipates rollups, particularly those employing L1 sequencing like Taiko, to function. Joaquin Mendes, COO of Taiko, commented that Fusaka substantially impacts data flow, validator coordination, and transaction confirmation for rollups.
The Fusaka upgrade enhances Ethereum's data availability model, introduces deterministic proposer lookahead via EIP-7917, adjusts block parameters, and lays the groundwork for future, more intensive rollup activity. These technical adjustments are crucial for L1-sequenced rollups such as Taiko, influencing their operational mechanics.
What Is Fusaka and Why Does It Matter?
Ethereum heavily relies on rollups for transaction processing. Congestion or high costs on these rollups can impact the entire ecosystem. Fusaka aims to alleviate these issues by optimizing how Ethereum handles the data published by rollups.
The primary objectives of Fusaka include:
- •Increasing the volume of Layer 2 data Ethereum can securely manage.
- •Reducing blob costs to make rollups more economical.
- •Improving validator efficiency.
- •Strengthening the network's resistance to spam.
- •Preparing Ethereum for the long-term vision of Danksharding.
This upgrade builds upon previous Ethereum developments, such as The Merge which introduced proof-of-stake, and Pectra, which enhanced wallet functionality and validation rules. Fusaka now specifically targets the scaling of Ethereum's data layer, which serves as the foundational element for rollups like Taiko. For Taiko, the data availability enhancements and deterministic proposer lookahead are particularly significant, directly influencing the operation of L1-sequenced rollups.
How Does Fusaka Change Ethereum’s Data Model?
A central feature of Fusaka is PeerDAS, which fundamentally alters how Ethereum verifies the large data blobs published by rollups.
Introduction to PeerDAS
PeerDAS stands for Peer Data Availability Sampling. It modifies the process by which Ethereum validates the extensive "blob" data that rollups submit.
Before Fusaka
Previously, every validator was required to download entire blobs. This approach was manageable when rollups generated less data but became a significant burden for home stakers with standard internet connections.
After Fusaka
With Fusaka, validators are now only responsible for verifying small portions of the data. Through erasure coding techniques, Ethereum can still reconstruct the complete data set even if each validator only processes a fraction of it.
What PeerDAS Achieves
- •Enables up to eight times greater throughput for rollup data.
- •Reduces bandwidth usage for validators by approximately 85 percent.
- •Promotes greater decentralization by lowering hardware requirements for home stakers.
- •Facilitates faster settlement of rollup transactions.
This mechanism is akin to verifying a book by checking random pages rather than reading it entirely. If sufficient individuals verify different pages, the integrity of the full book can be confirmed. This is a critical component of Ethereum's long-term scaling strategy, making large rollup ecosystems viable without demanding data center-level hardware for the network.
Is Fusaka Changing Ethereum’s Role?
According to Mendes, Fusaka represents a practical shift in Ethereum's role. Instead of attempting to manage all aspects of execution, computation, and settlement, Ethereum is solidifying its position as a secure base layer for data availability and consensus.
“L1 isn’t trying to do everything for everyone anymore. It’s becoming infrastructure for data availability and consensus coordination, assuming rollups will handle execution.”
- Joaquin Mendes, Taiko COO
This aligns with the current state of the ecosystem, where the majority of high-volume activity occurs on rollups. Fusaka reinforces this model by reducing the cost for rollups to post data and simplifying the process for validators to maintain network integrity.
However, this also introduces new requirements, such as the need for reliable blob access for rollups. Mendes points out that this necessitates running beacon clients in semi-supernode or supernode configurations. This is a trade-off for increased throughput, requiring more robust infrastructure for rollup operators who heavily utilize blobs. Taiko accepts this requirement due to the substantial benefits it offers to its architecture.
What Does EIP-7917 Do and Why Does It Matter for Taiko?
EIP-7917, a key component of Fusaka, introduces deterministic proposer lookahead. This feature provides Ethereum's Beacon Chain with advance knowledge of upcoming block proposers for the next epoch.
Why This Matters
This visibility allows rollups to coordinate with future block proposers, eliminating the need to wait for blocks to be finalized. This capability enables preconfirmation mechanisms, permitting a rollup to commit to transaction inclusion before the block is officially recorded on-chain.
Joaquin Mendes explains:
“Rollups can now commit to transaction inclusion with upcoming validators instead of waiting for blocks to land. For based rollups specifically, this matters.”
A "based rollup" utilizes Ethereum's L1 as its sequencer. Taiko operates under this model. Visibility into upcoming block proposers provides Taiko with architectural advantages that are difficult for other rollups to replicate.
Practical Benefits for Taiko
- •Enables preconfirmations for transactions.
- •Increases predictability in sequencing latency.
- •Allows the rollup to synchronize its architecture with Ethereum's timing.
- •Simplifies the management of risks associated with reorg-related delays.
These advantages are significant for any rollup designed around L1 sequencing.
Fusaka’s Phased Rollout and What It Signals
Fusaka's implementation is being rolled out in phases:
- •December 3: Fusaka activation.
- •December 9: Blob Parameter Only fork.
- •January 7: Second Blob Parameter Only fork.
These subsequent "parameter-only" forks allow Ethereum to incrementally increase blob capacity without requiring a full hard fork. This approach enables the network to adapt to demand more frequently and with reduced complexity.
Mendes highlights this as an evolution in Ethereum's upgrade strategy:
“Ethereum can now iterate on DA capacity as demand requires rather than waiting for major upgrades.”
This adaptability provides rollups with greater planning clarity. For Taiko, it ensures a predictable scaling path that aligns with its L1 sequencing model.
Does Fusaka Affect Block Capacity and Fee Stability?
Fusaka boosts the effective block gas limit from approximately 36 million to around 60 million. It also introduces new regulations concerning blob pricing and block sizes.
Key changes include:
- •EIP-7918: Modifies blob fee pricing mechanisms.
- •EIP-7934: Implements safeguards against oversized blocks.
- •EIP-7825: Introduces transaction gas limits within blocks.
Why These Changes Matter
- •Rollups gain more predictable slots for posting data.
- •Layer 2 fees are expected to stabilize.
- •The severity of congestion spikes is reduced.
- •Ethereum's reliability during periods of high activity is enhanced.
These adjustments support the objective of positioning Ethereum as a robust data availability layer, rather than a bottleneck for general settlement.
How Fusaka Improves Daily User Experience
While most users will not need to take direct action, the benefits of Fusaka will be evident across the ecosystem:
- •Reduced fees on rollups.
- •Fewer transaction failures during peak market activity.
- •More stable execution for decentralized finance (DeFi) applications.
- •Increased responsiveness of applications.
Biometrics and secp256r1
Fusaka incorporates support for the secp256r1 signature scheme. This advancement facilitates the use of built-in smartphone hardware security features for transaction signing. In the future, users may be able to approve transactions using biometric authentication like Face ID or fingerprint sensors, rather than relying on typing seed phrases. This feature complements existing wallet functionalities and expands design possibilities for wallet developers.
Conclusion
The Fusaka upgrade significantly enhances Ethereum's data availability, lowers rollup costs, strengthens validation processes, expands block capacity, and enables deterministic proposer lookahead. These improvements benefit the entire Ethereum ecosystem, offering particular advantages to L1-sequenced rollups like Taiko. Fusaka provides Ethereum with a more efficient foundation and offers Taiko a clearer architectural path forward. By focusing on capability enhancements rather than speculation, Fusaka's impact is already shaping how rollups prepare for the next phase of Ethereum's scaling roadmap.
For Taiko, Fusaka amplifies the benefits of L1 sequencing. Deterministic proposer lookahead, increased blob capacity, and more predictable data availability empower Taiko to refine its architecture in ways that are difficult for other rollup models to replicate.
Resources
Ethereum on X: Announcement (Dec. 3)
Consensys Fusaka dashboard: About Fusaka upgrade
Report by Blockworks: Ethereum’s Fusaka upgrade lands today
Taiko docs: About Taiko