Ethereum Fusaka Upgrade: Enhancing Capacity and Efficiency

Ethereum Fusaka Upgrade Overview

(Image source: ethereum)

Ethereum’s mainnet activated the Fusaka upgrade on December 3, 2025, a major update aimed at expanding the blockchain’s processing capabilities. The upgrade increases the per-block gas limit from 45 million to 150 million, enabling the network to handle significantly more transactions and smart contract executions per block.

Beyond raw capacity, Fusaka introduces new verification methods and optimized data structures, improving both efficiency and node performance.

Key Technical Features

1. PeerDAS: Lightweight Data Availability Verification

Traditional verification requires nodes to download large blob datasets to confirm the integrity of blocks and transactions. PeerDAS streamlines this process:

• Validators only sample portions of the data from multiple nodes
• Full blob downloads are no longer required
• Storage and bandwidth demands are greatly reduced

This innovation allows nodes to efficiently verify data availability without excessive resource usage.

2. Verkle Trees: Optimized State Data Structure

The Verkle tree is a compressed and optimized data structure that accelerates state verification:

• Reduces proof size
• Speeds up node synchronization
• Enhances storage efficiency

As Ethereum’s state grows, this improvement becomes crucial for maintaining performance and scalability.

3. Higher Gas Limits: More On-Chain Capacity

Fusaka raises the per-block gas limit, enabling:

• Increased transaction throughput
• Execution of more complex smart contracts
• Improved efficiency for Layer 2 blob data sharing

While boosting capacity, this also requires nodes to process larger data volumes efficiently.

Why Fusaka Matters

Ethereum’s ecosystem—including DeFi, NFTs, dApps, and Layer 2 solutions—has grown rapidly, often causing high fees and network delays during peak periods. Fusaka addresses these challenges by:

• Expanding transaction processing space
• Reducing verification workload
• Introducing smarter data structures

These improvements allow Ethereum to scale while preserving decentralization and security.

Conclusion

The Fusaka upgrade represents a significant step forward in Ethereum’s evolution. By combining higher gas limits, PeerDAS, and Verkle tree structures, the network achieves greater throughput while maintaining decentralization and security. Fusaka not only enhances the current user experience but also lays the foundation for the ecosystem’s future growth and scalability.