Key Half Life 1.1 -

Where ( u ) is the number of uses, and ( \lambda ) is the leakage coefficient—a number you must empirically measure, because every system has its own.

So when you generate that new RSA-4096 or Ed25519 key, do not ask "How long will this last?" Ask: "What is its half-life under load?" And if the answer is less than the life of your session, you are finally building for the world as it is—not as 1.0 wished it to be. key half life 1.1

[ P(t, u) = 2^{-t/T} \cdot (1 - e^{-\lambda u}) ] Where ( u ) is the number of

Version 1.0 of key half-life was simple. It said: After time T, a cryptographic key has a 50% chance of being compromised. That was the era of Moore’s Law as a gentle slope, where attack surfaces were smaller and trust was implicit. But threats don't stand still. It said: After time T, a cryptographic key