Algorand Edges Out XRP Ledger in Quantum Resistance

Algorand and XRP Ledger are two prominent blockchain networks that have been working to address the threat of quantum computing. The risk of signature forgery in a post-quantum scenario is relevant for institutions that hold balances in addresses with exposed public keys, as an attacker could derive a private key and sign unauthorized transfers.

Algorand has implemented Falcon signatures on its mainnet since August 2026, providing users with the ability to create accounts resistant to Shor's algorithm. However, Algorand's consensus layer is not fully post-quantum, as it still relies on Ed25519 and a vulnerable VRF. On the other hand, XRP Ledger follows a full-stack migration strategy, aiming for complete post-quantum readiness by 2028.

XRP Ledger has native key rotation, which simplifies preserving addresses and history during a migration. However, its primary technical challenge is the larger signature size of ML-DSA, which can impact storage, bandwidth, and verification cost. Algorand requires creating new accounts for native Falcon signatures, which can complicate accounting and listings.