TL;DR

• The increasing storage demands present significant challenges for Ethereum nodes.
• Some clients have started to prune the historical data due to storage constraints, leading to inconsistent storage behaviors among full nodes in the network.
• To ensure alignment across all clients, historical data pruning is being standardized in EIP-4444 and EIP-4844
• Consequently, recovering the latest L1 or L2 state by replaying historical data relies on centralized, out-of-protocol services, prompting the exploration of more decentralized Ethereum-aligned solutions
• Ethereum Portal network is a lightweight, decentralized P2P network for all types of Ethereum data including historical data. It is designed for resource-constrained devices and provides Ethereum JSON-RPC service. The historical network and beacon network are almost ready to use.
• EthStorage network is an incentivized modular storage network for EIP-4844 BLOBs. To store a BLOB, a user calls the L1 storage contract put() method to record the BLOB hash with a storage fee in ETH. The fee will be gradually distributed to storage providers upon submitting a proof of storage of off-chain BLOBs over time. The EthStorage testnet is running on Ethereum Sepolia testnet with multiple community participants successfully proving their local storage.
• Future initiatives include the development of a decentralized Ethereum state network, the implementation of proof of storage for dynamic-sized data, and decentralized access directly from browsers.

Acknowledgement: Many thanks Piper Merriam from EF, Karthik Raju from Polychain, Qiang from EthStorage for providing feedback of the article.

Background

On Oct 22, 2023, Péter Szilágyi, the renowned Go-Ethereum (Geth) dev lead, expressed his deep concerns on Twitter. He pointed out that while Geth clients preserve all historical data, other Ethereum clients like Nethermind and Besu can be configured to prune historical Ethereum data, such as historical block bodies and headers. This makes all clients inconsistent and is unfair to Geth. It sparked intense discussions and debates surrounding the Ethereum Storage problem within the Ethereum roadmap.

The Storage Challenge

Why do Nethermind and Besu opt to cease storing historical data? What issues underlie this decision? From our perspective, there are two primary root causes:

• The storage requirements for an Ethereum client are becoming increasingly demanding.
• There is no in-protocol incentive or penalty to store Ethereum historical data.

The first reason stems from the escalating storage demands of running an Ethereum client. To delve into the specific requirements, the following pie chart illustrates the distribution of storage for a fresh Geth node, as of block 18,779,761 on December 13, 2023

where