Author: Ye Huiwen, Wall Street Insights
Ethereum is currently undergoing a key network upgrade called "Fusaka," marking another significant milestone in its ongoing expansion roadmap. This upgrade aims to further reduce transaction costs on Layer-2 networks by significantly increasing data capacity and optimizing protocol efficiency, thus solidifying Ethereum's core position as a globally efficient settlement layer.
The Fusaka upgrade was activated at block height 13,164,544, as planned. This marks another step forward for Ethereum in its scalability roadmap, following the Dencun and Pectra upgrades. Kenny Lee, head of crypto at Goldman Sachs, noted that Fusaka represents the next phase of Ethereum's scalability roadmap, aiming to drive the network's evolution into a settlement layer that is both globally impactful and cost-effective.
The most significant change in this upgrade is the introduction of "PeerDAS" (Peer Data Availability Sampling) technology. This feature aims to theoretically increase the data capacity of the Layer-2 network by eight times, thereby achieving higher transaction throughput and potentially significantly reducing transaction fees for Layer-2 users.
Furthermore, the Fusaka upgrade includes the introduction of a "Blob-only" (BPO) fork mechanism, making future network capacity increases more flexible ; it also optimizes Layer-1 mainnet performance through features such as storage expiration and block control, and improves wallet functionality and user experience . These changes collectively constitute a structural leap for Ethereum in terms of scalability, sustainability, and operability.
From Dencun to Fusaka: Focusing on Scaling and Infrastructure Optimization
The Fusaka upgrade is actually a simultaneous activation of the consensus layer "Fulu" upgrade and the execution layer "Osaka" upgrade. According to the final plan confirmed by the Ethereum Foundation, the Ethereum Improvement Proposals (EIPs) included in the upgrade primarily focus on three areas:
These three directions are entirely consistent with the strategic priorities established by the Ethereum Foundation in April 2025 (expanding the Ethereum mainnet, expanding Blobs, and improving user experience). This article will focus on its improvement of Layer-2 data capacity and optimization of the fee mechanism.
Core Mission: A Path to Expansion Centered on L2 Level 2
To understand why Ethereum focuses on scaling through Layer-2, it's necessary to review its design philosophy.
In the "blockchain trilemma" (the inability to simultaneously achieve decentralization, security, and scalability), Ethereum's early design prioritized decentralization and security for its Layer-1 layer. This led to bottlenecks in Layer-1, such as high transaction fees and slow confirmation times, as the demand for decentralized applications grew.
To address this issue, Ethereum adopted a "Rollup-centric" roadmap. This strategy offloads the vast majority of transaction processing tasks to the Layer-2 network, where transactions are executed off-chain, and then the compressed data is published back to Ethereum Layer-1 for final settlement and security.
This modular approach allows Ethereum to achieve scalability without sacrificing its core decentralized principles. However, it also raises a new "data availability" problem—how to prove to the entire network that the published compressed data is valid without requiring every node to download the entire data.
PeerDAS: The Key to 8x Data Capacity Growth
PeerDAS, the most influential feature in the Fusaka upgrade, was created precisely to address the aforementioned data availability issues.
Prior to Fusaka, although the Dencun upgrade introduced "Blobs" as a cost-effective Layer-2 data storage method, each Ethereum full node still needed to download the complete Blob data, which limited the network's bandwidth and throughput limits.
PeerDAS fundamentally changes this model. After the upgrade, the network segments the Blob data into smaller pieces and distributes them across different nodes. Each node only needs to download and verify a small portion (approximately 1/8) of the total data, ensuring the availability and integrity of the entire dataset through cryptographic methods. This mechanism significantly reduces the resource requirements of individual nodes, theoretically resulting in approximately eight times the data capacity increase for the network. PeerDAS lays the foundation for subsequent Blob expansion and is a key driver in reducing Layer-2 transaction costs.
BPO fork: More flexible increases in Blob cap
As Layer-2 trading activity continues to grow, the demand for Blob space is also rising.
According to Coinmetrics data, the daily number of blobs is trending upwards. However, under the current mechanism, increasing the number of blobs per block requires a complex "hard fork," and such major upgrades are difficult to coordinate and occur infrequently.
To address this bottleneck, Fusaka introduced a "Blob-only (BPO) fork" mechanism. This is a dedicated, lightweight fork used solely to update parameters related to blobs (such as the maximum number of blobs per block). Due to its small scope and manageable impact, development teams can deploy such upgrades more frequently and safely, enabling the network to incrementally increase its data capacity without waiting for major upgrades that include other features. According to the Ethereum Foundation, the BPO fork will be pre-programmed to double the number of blobs in stages over several weeks until it reaches its maximum value.
Stabilizing the fee market: Introducing a Blob floor price mechanism
After the Dencun upgrade, Layer-2 servers face two separate fees when publishing data to Ethereum: execution gas and blob gas. While blob gas fees may drop to near zero when demand is low, Layer-2 servers still incur potentially substantial execution gas costs. This “price signal failure” can lead to pricing inefficiency and market instability.
To address this issue, Fusaka introduced a "floor price" mechanism for blobs through EIP-7918. This floor price is not a fixed value, but is dynamically linked to the execution gas cost.
When the market-driven Blob fee falls below this floor, the fee adjustment algorithm will prevent it from decreasing further. This is designed to ensure that the Blob fee always reflects its economic value, keep the fee market sensitive to network congestion, and provide a more stable and predictable pricing environment for Layer-2.
Market impact and potential risks
The Fusaka upgrade is expected to have a profound impact on the market. The increased data capacity resulting from the PeerDAS and BPO forks is expected to further reduce the operating costs of Layer-2 networks. Meanwhile, the floor price mechanism of EIP-7918 ensures that Blob space is not used unreasonably cheaply, maintaining the network's economic sustainability. This may intensify competition among Layer-2 networks, shifting the focus from transaction costs to user experience, ecosystem cooperation, and liquidity depth.
However, this upgrade also comes with some risks and considerations:
