Bitcoin News
By James Thorp
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What SHRINCS Actually Does. The scheme is already running on Blockstream's Liquid sidechain.
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The Key Management Problem. SHRINCS uses one-time keys. They're stored on devices.
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Lattice Schemes and the ZK Proof Question. Blockstream's research isn't locked onto SHRINCS alone.
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A new Bitcoin Improvement Proposal is live. It covers SHRINCS, an experimental post-quantum signature scheme that Blockstream has been quietly developing, and it's already…
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Blockstream, led by CEO Adam Back — who's publicly skeptical about how close quantum computing actually is to threatening Bitcoin — pushed the proposal forward anyway.
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The scheme is already running on Blockstream's Liquid sidechain. It got tested there in March, which gives it at least some real-world footing — though the cryptographic…
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Here's the core tension: current NIST-endorsed post-quantum schemes are massive compared to what Bitcoin uses today. Bitcoin's Schnorr signatures sit at 64 bytes.
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But there's a partial fix baked in. Under Bitcoin's Segregated Witness protocol, the weight of those larger signatures gets partially absorbed.
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That said, each SHRINCS signature grows by 16 bytes with each use. Scalability questions don't disappear just because SegWit softens the blow.
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SHRINCS uses one-time keys. They're stored on devices. And that's where things get complicated fast — because key reuse is a serious risk with stateful signature schemes like…
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Lose your device data? You're looking at a large fallback transaction to recover. The mechanics work, but they add a layer of responsibility that most Bitcoin users probably…
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More context: Bitcoin Futures See Crypto Collateral Plummet to Just 12% as Stablecoins Rise
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Compare that to something like SPHINCS+, a stateless scheme that uses multi-layer hash trees to sidestep the key-reuse problem entirely. No state to manage, no device dependency.
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Blockstream also introduced SHRIMPS in March — a companion scheme meant to support backup devices that can co-sign transactions from the same seed.
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Blockstream's research isn't locked onto SHRINCS alone. The team has been looking at lattice-based signature schemes too.
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