Ripple has announced a phased roadmap to achieve quantum-resistant upgrades for its XRP Ledger by 2028. This plan includes developing a "Quantum-Day" contingency plan to address potential quantum computing threats and collaborating with Project Eleven for preliminary testing and validation. Ripple states that this move aims to prepare for a post-quantum-secure transition, and the entire plan will proceed in four phases: Phase 1: Q-Day Contingency Preparedness (Already Underway). Establishing a Quantum Day (Q-Day) contingency response mechanism. If the existing classical encryption system is suddenly compromised, the network will immediately stop accepting traditional public-key signatures and forcibly migrate to quantum-secure accounts. Phase 2: Risk Assessment and Algorithm Testing (First Half of 2026). Comprehensively assessing the impact of post-quantum cryptography on the XRP Ledger network performance, storage, and bandwidth. Collaborating with Project Eleven to conduct validator-level testing and Devnet benchmarking, deploying the NIST-standardized ML-DSA quantum-secure signature scheme, and developing a post-quantum escrow wallet prototype. Phase 3: Devnet Hybrid Integration (Second Half of 2026). Integrate candidate post-quantum signature schemes in parallel 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 for confidential transfers to advance the privacy and compliance capabilities of tokenized real-world assets on XRPL. Phase Four: Full Mainnet Upgrade (Target 2028). Submit a formal protocol amendment, which, after being approved by validators, will fully enable native post-quantum cryptography on the mainnet. (Cointelegraph)