The recent advancements in quantum computing have sparked concerns about the potential risks to legacy blockchains. Experts suggest that XRP's architecture may be better equipped to handle these threats than Bitcoin's. XRP operates on the XRP Ledger, an open-source and decentralized blockchain, which is utilized by Ripple for cross-border transactions. A key difference lies in the exposure of public keys, which can be reverse-engineered by a sufficiently powerful quantum computer.
In the case of XRP, around 300,000 accounts holding 2.4 billion XRP have never sent funds and thus have not exposed their public keys. These accounts are considered quantum-safe by default. However, dormant whale accounts that have transacted in the past and exposed their public keys are at risk. 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.
This is in contrast to Bitcoin, where a significant portion of early coins were mined using a format that exposed public keys directly. Approximately 6.9 million BTC are estimated to be vulnerable, accounting for nearly 35% of Bitcoin's circulating supply. Bitcoin's lack of a key rotation feature leaves holders with the option of moving funds to a new address, but this process exposes the public key of the old address. While the risks are still theoretical, they highlight the relative structural vulnerability of Bitcoin compared to XRP.