Proposal for Quantum-Resistant Address Migration Protocol (QRAMP) BIP

The discussion on the transition to quantum-resistant addresses in blockchain technology raises a significant concern regarding the potential for network congestion and artificially inflated transaction fees. The limited block size inherent to many blockchain networks could be exploited by those who stand to gain from higher fees, by flooding the network with bogus transactions. This manipulation would force users to pay exorbitant fees to move their funds before a given deadline or risk losing them entirely. Such a scenario underscores the challenges of implementing a mandatory switch to quantum-resistant addresses without causing undue hardship for users.

A more nuanced approach to enhancing quantum resistance within blockchain systems is suggested, focusing initially on disabling spending from specific types of outputs that lack inherent quantum resistance. Outputs like Pay-to-PubKey (P2PK) and Pay-to-Taproot (P2TR), which do not utilize hashed public keys, are highlighted as more vulnerable and thus should be targeted first for restrictions. Conversely, outputs that incorporate hashed public keys, such as Pay-to-PubKey-Hash (P2PKH) and Pay-to-Witness-PubKey-Hash (P2WPKH), offer a greater degree of protection against quantum computing attacks and could remain active for a longer period.

The threat posed by quantum computing to blockchain security is not immediate but is expected to grow over time. Current analyses suggest that quantum computers would initially struggle to derive private keys from known public keys quickly enough to intercept transactions before they are confirmed on the blockchain. This temporal gap provides a window during which the risk of quantum attacks remains relatively low. Moreover, the option to transmit transactions directly to trusted miners, rather than broadcasting them publicly, could serve as a temporary safeguard against quantum decryption attempts.

Despite these interim solutions, the eventual disablement of Unspent Transaction Outputs (UTXOs) with hashed public keys may become necessary. The issue of address reuse exacerbates this vulnerability, as it increases the likelihood of public key exposure. As quantum computing technology advances, the probability of decrypting private keys rapidly enough to affect transaction security before confirmation could increase to a worrying level. This evolving threat landscape suggests that while immediate wholesale changes to disable all potentially vulnerable outputs may not be advisable, a phased approach to enhancing quantum resistance is crucial for maintaining the integrity and security of blockchain networks.