Ethereum Advances to Final Testnet Phase in Preparation for Fusaka Upgrade Mainnet Rollout

Ethereum has officially entered the last testnet phase for its highly anticipated Fusaka upgrade, according to a report by Cointelegraph on October 21. Scheduled for mainnet deployment on December 3, this upgrade represents a critical step forward in Ethereum's roadmap. Central to the Fusaka upgrade is the introduction of a transaction gas limit cap of approximately 16.78 million gas units, aimed at improving the network's block efficiency and supporting the future shift to parallel processing.

This gas limit mechanism has already been successfully implemented on Ethereum's Holesky and Sepolia testnets. Prior to this adjustment, a single transaction could monopolize the entire block gas capacity of approximately 45 million gas units, increasing the likelihood of DDoS attacks and limiting scalability. By capping the gas limit per transaction, Ethereum seeks to ensure more equitable distribution of computational resources within each block. This improvement not only enhances scalability but also paves the way for better handling of simultaneous transactions, fostering a balanced and efficient network ecosystem.

Optimizing Network Activity with Gas Limit Caps

The introduction of individual transaction gas limits marks an important step in Ethereum’s evolution. By preventing any one transaction from consuming all available block resources, the network can accommodate smaller transactions more efficiently and predictably. This structural change lays the groundwork for Ethereum's eventual adoption of parallel execution, enabling multiple transactions to be processed concurrently, thereby addressing scalability challenges inherent to blockchain networks.

Key Features and Milestones of the Fusaka Upgrade

As part of the Fusaka upgrade process, Ethereum has implemented further improvements to its testnet environments. The Sepolia testnet recently experienced an increase in block gas limits from approximately 45 million to 60 million gas units. Another significant testnet milestone is set for October 28, when the upgrade will be activated on the Hoodi testnet. Following these steps, Fusaka's mainnet launch is slated for December 2025.

Fusaka Upgrade (EIP-7825) is a pivotal release in Ethereum’s upgrade trajectory, bridging key milestones between earlier and future deployments, such as the Dencun upgrade planned for March 2024 and the Pectra upgrade scheduled for May 6, 2025. Specific highlights of Fusaka include:

• Base block gas limit increase: The overall block gas limit rises to 60 million units, creating room for more transactions.
• Transaction gas cap: An individual transaction gas cap of approximately 16.77 million units ensures fair resource allocation.
• PeerDAS (Peer Data Availability Sampling): This innovative feature allows Ethereum nodes to store smaller, randomized chunks of Layer 2 "blob" data rather than the entire dataset. This considerably reduces hardware requirements while preserving network security and supports the low-cost and high-throughput functionality of Ethereum’s Layer 2 ecosystem.

The introduction of PeerDAS offers significant advantages for Ethereum’s scalability. By minimizing hardware demands, the network bolsters its capacity to grow Layer 2 solutions, making it more accessible for developers and enhancing overall transaction efficiency.

The Evolution Continues: Post-Fusaka Plans

Following the Fusaka upgrade, Ethereum will pivot toward its next developmental milestone, dubbed "Glamsterdam." This subsequent upgrade will focus on introducing EIP-7928, which serves as the foundation for Ethereum's transition to full parallel transaction processing. Specifically, Glamsterdam aims to enhance the network’s execution layer, taking further steps toward scalability and efficiency improvements.

Gabriel Trintinalia, a protocol engineer with Consensys’ Besu client team, shed light on the vital role of testnet phases in a recent interview with Cointelegraph. “These testnet upgrades are critical in providing client teams, validators, and the ecosystem with the confidence to evaluate performance, identify edge cases, and fine-tune parameters before the mainnet hard fork,” Trintinalia explained.

The testnet phases not only validate the features planned for each upgrade but also provide an opportunity to refine the protocol, ensuring a smoother transition for the Ethereum ecosystem when these changes are deployed on the mainnet.

Conclusion

As Ethereum nears the December 3 mainnet rollout of the Fusaka upgrade, the network is making significant strides in scalability and efficiency. From introducing transaction gas caps to bolster security and resource distribution, to advancing Layer 2 functionality through the PeerDAS feature, Fusaka represents a transformative step in Ethereum’s roadmap. With Glamsterdam and parallel transaction processing developments on the horizon, Ethereum continues to set a strong foundation for the future growth of decentralized applications and blockchain technology.