Harvest-now-decrypt-later risk

HNDL means adversaries capture ciphertext today and decrypt it after quantum computers mature. Healthcare, finance, and government data with decades of shelf-life are highest risk.

Superposition

Compare feasible plans before you collapse to one.

Phase

Feasibility first, then rank against the operational objective.

Measurement

Ranked plan, short why, and the metric behind the call.

Mosca inequality

When data shelf-life plus migration time exceeds the quantum timeline, you have exposure now. See /q-day/mosca-inequality for the interactive calculator.

Resources to open next

The goal of this guide is to help you navigate toward the right tools, not stop at the overview. The resources below are the strongest next clicks for this topic.

open-quantum-safePost-quantum cryptography

liboqs

C library for prototyping and experimenting with quantum-resistant cryptography

CFlagship

2,946 stars · Updated 7d ago

Next step

HNDL primer.