pcrzero academy · a visual field guide · beginner to expert

Platform Configuration Registers & PCR0
A Visual Path to Expertise

Every core idea leads with a diagram. Every acronym is spelled out in plain language the first time it appears. This track takes you from first principles to authoritative command of measured boot and attestation — its genesis, history, use today, and future.

beginner → expert9 phases diagram-firstevery acronym defined labs + mastery gates

First, the words behind the letters. A PCR is a Platform Configuration Register — a special memory slot inside a security chip. PCR0 is simply the first of those slots, and it holds the fingerprint of the very first software that runs. Everything in this course is about how that fingerprint is made, chained, signed, and checked. Keep the picture below in your head — the entire field is this one loop, drawn again and again in different hardware.

① Root of Trust the first code you are forced to trust ② Each next component firmware → boot loader → kernel → your app ③ PCR — the hardware register append-only; can be added to, never rewritten ④ Event Log the plain list of everything measured, in order ⑤ Quote (the signed evidence) PCR values + a fresh random challenge, hardware-signed ⑥ Verifier decides replays the log, checks the signature → trust or reject measures (hashes) it before it runs extend the fingerprint in also written down, in words packaged & signed sent to a checker
The whole field in one picture. Master this loop and every platform later is just a re-drawing of it. The math in step ③ is one line: new value = Hash( old value ‖ new measurement ), where "‖" means "stuck together end to end."

How to read this track. Each phase opens with a diagram, then gives you the short spoken-language explanation, the primary sources (the original specifications — the real authority), a hands-on lab, and a mastery gate (a "draw or build this from memory" test). Because you learn visually: redraw each phase's diagram from memory before moving on. When you can redraw all of them, you are the expert.