The emergence of quantum computing has sparked concerns about the potential vulnerability of legacy blockchains. However, experts believe that XRP's architecture provides a level of protection against quantum threats that surpasses that of Bitcoin. XRP operates on the XRP Ledger, an open-source and decentralized blockchain, which is utilized by Ripple for facilitating cross-border transactions. A key difference lies in the exposure of public keys, which can be reverse-engineered by a powerful quantum computer running Shor's algorithm, potentially draining funds.
Typically, public keys are exposed when sending transactions, making account activity a determining factor in quantum vulnerability, rather than the balance or the duration of holding an address. A recent audit of the XRP Ledger found that approximately 300,000 accounts, holding 2.4 billion XRP, have never sent funds and thus have not exposed their public keys, rendering them quantum-safe by default.
In contrast, dormant 'whale' accounts that have transacted in the past and exposed their public keys are at risk, with two such accounts found to hold 21 million XRP, equating to 0.03% of the circulating supply. The XRP Ledger's feature of signing key rotation allows users to change their signing key without moving funds, providing an additional layer of security. Moreover, the 'escrow feature' with a time lock offers protection against quantum risk, as funds locked in escrow are safe due to logical constraints rather than cryptography.
While Bitcoin faces a greater quantum threat due to the sheer scale of vulnerable coins, including Satoshi Nakamoto's 1 million BTC, and the lack of a key rotation feature, experts note that Bitcoin developers are working on proposals to develop quantum resistance.