Ripple announces quantum resistance roadmap, aiming to make the XRP Ledger quantum-resistant by 2028.

Mars Finance reports that on April 21, Ripple officially released the quantum resistance roadmap, with the core goal of making the XRP Ledger (XRPL) resistant to quantum attacks by 2028. The roadmap mainly addresses the potential threat of “harvest now, decrypt later” (Harvest now, decrypt later) attack models, where attackers collect encrypted data now and wait for future quantum computers to mature before decrypting. The entire plan will be carried out in four phases:
First phase: Q-Day emergency preparedness (already initiated). Establish a quantum day (Q-Day) emergency response mechanism. If the current classical encryption system is suddenly broken, the network will immediately stop accepting traditional public key signatures and force a migration to quantum-safe accounts. At the same time, explore asset ownership verification schemes based on post-quantum zero-knowledge proofs (Post-Quantum ZK-proofs), allowing existing account holders to securely recover funds in emergencies without exposing vulnerable keys.
Second phase: Risk assessment and algorithm testing (first half of 2026). Conduct a comprehensive evaluation of the impact of post-quantum cryptography on XRP Ledger network performance, storage, and bandwidth. Collaborate with Project Eleven to carry out validator-level testing and Devnet benchmarking, deploy NIST-standardized ML-DSA quantum-safe signature schemes, and develop prototypes of post-quantum custody wallets. Lead engineer Denis Angell has already deployed ML-DSA signatures on XRPL’s AlphaNet.
Third phase: Devnet hybrid integration (second half of 2026). Parallel integration of candidate post-quantum signature schemes with existing elliptic curve signatures on the developer network (Devnet), allowing developers to test performance and system impact without affecting the mainnet. Simultaneously, explore post-quantum zero-knowledge proof primitives and homomorphic encryption techniques for confidential transfers, advancing privacy and compliance capabilities of tokenized real-world assets on XRPL.
Fourth phase: Full mainnet upgrade (target 2028). Submit formal protocol amendments (Amendment), and upon validator approval, fully enable native post-quantum cryptography on the mainnet. Focus on production readiness optimization: throughput tuning, validator reliability assurance, and ecosystem coordinated migration, ensuring a complete transition without compromising network speed and settlement finality.