Blockstream researcher Jonas Nick has proposed a new quantum-resistant signature scheme designed for Bitcoin. This proposal aims to support secure multi-device signatures while keeping signature sizes smaller than current post-quantum standards.
SHRIMPS introduces multi-device quantum signatures
In a recent tweet post, Jonas Nick introduced SHRIMPS and explained that it is a hash-based construction. This allows multiple devices loaded from the same seed to independently generate approximately 2.5 KB signatures.
This is approximately three times smaller than the current post-quantum standard SLH-DSA, which produces a signature of approximately 7.8 KB. However, the smaller size increases efficiency while maintaining quantum-resistant security.
“Please welcome SHRIMPS to the family of stateful PQ signatures.” “SHRINCS provided sigs up to 324 bytes, but single device. SHRIMPS is multi-device capable.”
SHRIMPS solves multi-device wallet limitations
Previous work in this area, including SHRINCS, has produced impressively small signatures but has been limited to a single device. If you move the seed to a new device or run it across your backup hardware, you’ll fall back to a much larger stateless signature, compromising any efficiency gains.
SHRIMPS removes that constraint using several key design principles.
- Devices loaded from the same seed can independently generate compact signatures.
- The total number of devices is limited to a preset limit (typically 1,024).
- When the device loses state and reloads, it automatically reverts to compact path
- If you exceed your device’s limits, security degrades over time rather than collapsing.
Why now: Google factors
The proposal comes as the risks of quantum computing gain attention. Google researchers recently suggested that solving elliptic curve cryptography may require fewer resources than previously estimated.
Google researchers have shown that ECDLP-256, the standard that secures most blockchain networks, could theoretically be cracked using fewer than 1,200 logical qubits. This represents a roughly 20x reduction in hardware requirements from previous estimates.
Researcher Justin Drake called the day a “momentous day” and estimated there was at least a 10% chance that a quantum computer would be able to recover Bitcoin’s private keys by 2032.
Why is it important for Bitcoin?
Bitcoin keys are typically used for only a small number of signatures, and multi-device wallet setups are common. SHRIMPS is designed with both realities in mind. The important points are:
- Bitcoin’s current elliptic curve cryptography remains unbroken today.
- The threat lies in signature security, not mining
- Post-quantum upgrades require network-wide coordination and will take years to implement
- All wallets must be upgraded, even wallets that no one controls, like Satoshi’s wallet.
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