In 26 years of building security and cryptographic services at Cisco, I’ve worked through a long list of defects in protocols and systems. Only a small minority of the cryptographic failures I’ve seen came from someone breaking the algorithm. Far more often, systems fail in the gap between fix available and fix deployed.

That gap is the last mile of trust. It’s where a patch published upstream reaches a global product portfolio months later. It’s where an embedded device ships with a cryptographic library that will never be updated in its service life. It’s where a fix moves cleanly through four layers of a supply chain and quietly stalls at the fifth.

The math is the part we’ve mostly solved. Logistics are the part we…