Two Draft BIPs Aimed at Quantum Defense

Bitcoin (BTC) developers are drafting a defense against quantum computing attacks, and the work now takes the form of two concrete proposals: BIP-360 and BIP-361. Both are Bitcoin Improvement Proposals — the technical documents developers use to change how the network functions — and, as drafts, both remain subject to review and revision before any potential deployment.

How BIPs Shape Bitcoin's Development

Bitcoin Improvement Proposals (BIPs) are the formal mechanism through which changes to the network's consensus rules and technical standards are documented, debated, and adopted. The process, modeled on Python's PEP system, has guided past upgrades such as Segregated Witness (SegWit) in 2017 and Taproot in 2021. If consensus forms around a proposal, it is typically implemented in Bitcoin's reference software and deployed through a soft fork. Because Bitcoin has no central authority, changes of this kind depend on broad agreement among developers, node operators, and the wider community — a dynamic that has historically stretched major upgrades across years. As draft documents, BIP-360 and BIP-361 are still at the stage where their technical details can change.

Why Quantum Computing Is a Concern

Bitcoin transactions are authorized using elliptic-curve cryptography — the Elliptic Curve Digital Signature Algorithm (ECDSA) and, since Taproot, Schnorr signatures. Both are regarded as secure against classical computers, but a sufficiently powerful quantum computer running Shor's algorithm could, in theory, derive a private key from a public key.

Public keys become visible on-chain when coins are spent, and certain legacy output types from Bitcoin's earliest era expose them directly. Repeated reuse of the same address creates a similar surface, which is why researchers have long flagged older and reused outputs as the most vulnerable to a future quantum adversary. Any replacement for these signature schemes would itself touch Bitcoin's consensus rules, placing the response on the same agreement-driven upgrade path described above.

A Long-Term Risk Being Addressed Early

Experts generally characterize the quantum threat as long-term rather than imminent: today's quantum processors operate with far fewer error-corrected logical qubits than the thousands to millions that published estimates suggest breaking ECDSA would require. Even so, the possibility that large-scale machines may eventually be built has driven preparation across the technology sector, and the U.S. National Institute of Standards and Technology (NIST) finalized its first post-quantum cryptography standards in 2024, covering hash-based and lattice-based signature schemes.

BIP-360 and BIP-361 are part of that broader preparation effort, and their specific technical details remain under discussion among Bitcoin contributors. The signals to follow from here are rather than dramatic: revisions to the draft texts, the breadth of contributor engagement during review, and any change in their status within the BIP process — milestones that, for consensus-touching upgrades like SegWit and Taproot, historically unfolded over years.

Source and Attribution

This content was first published on COINOTAG: Bitcoin (BTC) Developers Weigh BIP-360 and BIP-361 Drafts to Cut Quantum Attack Risk (full version: COINOTAG), October 26, 2026.