Ethereum Foundation Abandons Poseidon, Shifts to Conventional Hash Functions for Post-Quantum Security
The Ethereum Foundation is pivoting away from the Poseidon hash function in its post-quantum architecture, opting instead for established algorithms like SHA and BLAKE as advances in cryptographic proofs make the specialized function obsolete.
Poseidon Loses Its Edge
The Ethereum Foundation is moving away from Poseidon, a specialized hash function that had been earmarked for future post-quantum systems, according to researcher Justin Drake. The shift represents a significant change in the foundation’s approach to quantum-resistant infrastructure. Poseidon had been considered a candidate for leanVM, a system designed to enable Ethereum to efficiently verify large volumes of blockchain activity. However, recent developments in cryptographic technology have rendered this specialized approach unnecessary. In its place, the foundation is turning toward more conventional, battle-tested hash functions such as SHA and BLAKE.
Technological Breakthrough Changes the Landscape
The decision stems from substantial progress in the field of SNARKs—compact cryptographic proofs that allow computers to verify complex computations without repeating the underlying work. These advances have leveled the playing field, enabling standard hashing algorithms to now perform at the efficiency levels that once gave Poseidon its main advantage. This development reshapes how Ethereum will approach its post-quantum transition. Additionally, collaborative efforts involving the Ethereum Foundation, Eigen Labs, and Succinct have achieved a 2.5-fold increase in proving speeds, further validating the feasibility of using traditional hash functions. Sreeram Kannan, founder and CEO of Eigen Labs, highlighted an additional benefit: established hash-based systems present fewer potential security vulnerabilities compared to alternative post-quantum approaches, and their extensive track record of scrutiny over many years reduces deployment risk.
Ethereum’s Post-Quantum Timeline
Drake outlined a forward-looking timeline for implementation. The foundation aims to have a production-ready version of leanVM completed in 2027, though he noted these dates remain preliminary and subject to change. Following that milestone, deployment across Ethereum’s consensus, data, and execution layers is targeted for 2028. This phased approach reflects the foundation’s cautious but deliberate strategy in implementing quantum-resistant technologies across the network’s critical infrastructure.
The transition away from Poseidon signals a maturation of post-quantum cryptography strategies in the blockchain space, where pragmatic security meets proven performance. By leveraging well-established cryptographic primitives alongside cutting-edge proof systems, Ethereum is positioning itself to defend against potential quantum computing threats while maintaining operational efficiency.
Source: Ethereum Foundation, via Cointelegraph. Not financial advice.