Ethereum Fusaka Upgrade: 12 EIPs Drive Scalability Evolution

The core developers of the Ethereum execution layer held their 214th meeting on June 20th, determining the final scope of the Fusaka upgrade. In addition to the original plan, an extra EIP (EIP 7939) was added, bringing the total to 12 EIPs covered by the upgrade. This marks the official transition of Fusaka from the planning phase to the substantive implementation phase.

As the largest hard fork bundled upgrade since The Merge for Ethereum, Fusaka is expected to be launched by the end of 2025. The industry generally believes that this will bring significant improvements to the L2 data space, and L2 transaction fees may further decrease in the next 1-2 years, thereby consolidating Ethereum's market position.

Ethereum Continuous Expansion Roadmap

The scalability issue of Ethereum has long been a core bottleneck for the high on-chain costs of the mainnet and the difficulty in popularizing DApps. According to publicly available data from April this year, Ethereum L1 currently has a throughput of 15 transactions per second, and the gas limit has recently been raised to 36 million, an increase of about 6 times over the past 10 years.

At the same time, Ethereum L2 has made significant progress. The current L2 throughput has reached about 250 TPS, achieving a huge leap in scalability. This improvement is not only reflected in the data, but many users have also truly felt the reduction in costs and the acceleration of on-chain operations.

In the past year, the transfer fees of several mainstream L2 networks have generally dropped to around $0.01, or even lower, achieving a decrease of one or more orders of magnitude compared to before. The daily Gas costs on the Ethereum mainnet have also become significantly more affordable (of course, this is also influenced by market conditions and on-chain activity levels).

This transformation is the result of Ethereum strictly implementing its roadmap and continuously iterating upgrades. Key upgrades to the Ethereum network in recent years include:

• In 2022, the upgrade to PoS mechanism through The Merge significantly reduced energy consumption, freeing up execution layer bandwidth for subsequent upgrades.
• The Dencun upgrade will be activated in 2024, introducing a Blob data mechanism to provide low-cost temporary storage for L2, significantly reducing Rollup costs.
• The Pectra upgrade will be completed on May 7, 2024, optimizing the validator operation process and enhancing the flexibility of participation in the PoS system.

The Fusaka upgrade is a key step in continuing the aforementioned process. According to the co-executive director of the Ethereum Foundation, the Fusaka mainnet is planned to go live in the third or fourth quarter of 2025, implementing several core EIPs, including PeerDAS, further pushing Ethereum to break through performance bottlenecks and move towards mainstream applications.

From The Merge to Dencun, Pectra, and then to Fusaka, Ethereum is steadily advancing towards its long-term blueprint, which aims to create a global network that combines security, scalability, decentralization, and sustainability.

Fusaka Upgrade Overview

The Fusaka upgrade includes 12 core EIPs, covering multiple technical dimensions such as data availability, node lightweighting, EVM optimization, and the collaborative mechanism between the execution layer and data layer.

The most notable is EIP-7594 (PeerDAS), which introduces the "Data Availability Sampling (DAS)" mechanism. This mechanism allows validators in the network to complete verification by downloading only a portion of the Blob data, without needing to store all the data in full. This greatly reduces the burden on the network, improves verification efficiency, and lays the foundation for L2's large-scale transaction processing capability.

The concept of Blob originates from EIP-4844 introduced in the Dencun upgrade of 2024. As the most important milestone for Ethereum in 2024, the Dencun upgrade enabled transactions carrying Blobs for the first time, allowing L2 to choose not to use the traditional calldata storage mechanism, thereby significantly improving the Gas fees required for transactions and transfers on L2.

Carrying Blob transactions refers to embedding a large amount of transaction data in a Blob, significantly reducing the storage and processing burden on the Ethereum mainnet. Blob data is not counted towards the Ethereum mainnet state, directly addressing the L1 cost issues related to data availability, ensuring that L2 platforms can provide cheaper and faster transactions without compromising the security and decentralization of Ethereum.

The May Pectra upgrade has increased the Blob capacity from 3 to 6. Ideally, Fusaka will expand the Blob capacity to 72 per block (initially possibly increasing to 12-24). In the future, if DAS is fully realized, the theoretical maximum capacity could reach 512 Blobs per block.

Once implemented, the processing capacity (TPS) of L2 is expected to soar to tens of thousands. This will significantly enhance the usability and cost efficiency of high-frequency interaction scenarios such as on-chain DApps, DeFi, social networks, and games.

At the same time, Fusaka also plans to achieve lightweight state and node structure by introducing Verkle trees. This not only significantly compresses the size of state proofs, making light clients and stateless verification possible, but also helps promote the decentralization of Ethereum and the popularization of mobile platforms.

In addition, Fusaka also focuses on the flexibility of the virtual machine layer (EVM) and performance bottlenecks, including the following proposals:

• EIP-7939 (CLZ opcode): Efficiently implements bit operations to accelerate cryptographic computations.
• EIP-7951 (secp256r1 alternative support): Enhancing compatibility with Web2 and enterprise architectures.
• EIP-7907: Expanding the contract size limit to support the deployment of more complex logic, enhancing developer flexibility.

To ensure that scaling does not affect network stability, Fusaka has introduced EIP-7934 to set block size limits, preventing blocks from becoming too heavy due to Blob scaling. At the same time, EIP-7892/EIP-7918 adjusts the fees for Blob usage to prevent resource abuse and dynamically match supply and demand fluctuations.

Ethereum Scalability and Experience Watershed

Fusaka is not only a technological upgrade but is also expected to lay the bridge "from scalability to usability" on multiple key levels.

For Rollup developers, this means lower data writing costs and more flexible interaction space. For wallet and infrastructure providers, it means supporting more complex interactions and heavier node environments. For end users, this will bring a lower cost and faster response on-chain operation experience. For enterprises and compliant users, EVM scaling and state proof simplification will make on-chain interactions easier to integrate with regulatory systems and large-scale deployments.

Fusaka is currently undergoing testing on multiple Devnets, and the final launch date may vary. Optimistically, Fusaka is expected to complete its mainnet deployment by the end of 2025, which could become another significant milestone in Ethereum's history following The Merge.

Overall, Fusaka is not only limited to enhancing on-chain scalability but also represents a key step for Ethereum in transitioning to mainstream commercial applications and ordinary users. It is expected to provide a solid technical foundation for the next phase of the Rollup ecosystem, enterprise-level Dapps, and on-chain user experience.

The true watershed for Ethereum's transition to large-scale mainstream applications may be approaching.