XRP Ledger (XRPL) has begun experimenting with next-generation encryption technology to counter the threat of quantum computing. A developer test network is being used to test the performance and practical applicability of quantum-resistant cryptography ahead of mainnet deployment.
Denis Angell, a software engineer at XRPL Labs, recently announced the integration of a quantum-resistant digital signature algorithm into AlphaNet, the developer network. The experiment, which utilizes CRYSTALS-Dilithium, a lattice-based cryptography, will test the network's core security structures, including account signing, transaction verification, and validator consensus.
Currently, most blockchains, including Bitcoin and Ethereum, use elliptic curve cryptography (ECC). While ECC maintains high security in conventional computing environments, its structural vulnerability has been pointed out: if sufficiently advanced quantum computers emerge, private keys can be decoded from public keys using the Shor algorithm. Dilithium, a quantum-resistant digital signature scheme (ML-DSA) adopted as a standard by the National Institute of Standards and Technology (NIST), was designed with this threat in mind.
However, the introduction of quantum-resistant cryptography comes with clear costs. While existing ECDSA signatures are approximately 64 bytes, Dilithium signatures are approximately 2.4KB. This can significantly increase network bandwidth and storage usage, and can also impact transaction processing speed and efficiency. XRPL's AlphaNet experiment is also aimed at verifying the balance between this enhanced security and reduced performance.
Industry forecasts are divided on the timing of the so-called "Q-Day," when quantum computers will render existing cryptographic systems ineffective. While some believe it will take decades, industry figures, including Ethereum co-founder Vitalik Buterin, have emphasized the need for early response, arguing that the quantum threat could materialize sooner than expected. Regardless of the timing of the threat, there is general agreement that proactive preparation is essential at the blockchain infrastructure level.
XRPL's latest experiment is considered one of the first examples of quantum-resistant cryptography being applied and verified in a real-world network environment among major public blockchains. Based on future test results, the decision to implement the mainnet and a phased transition strategy will likely be discussed.
