Certificates & chains of trust
P53.pki-trust.01 · Audience: guest, it-ml, language-pro · Prerequisites: Public-key crypto & signatures
Welcome to PKI, Certificates & TLS/HTTPS — the second pillar of the Security discipline, and the one that turns P52's primitives into the padlock in your browser. A certificate binds a name to a public key; a chain of trust links it up to a root your machine already trusts. This track builds the walk that decides whether to trust a server at all.
Same thread as every module here: concept → protocol → attack → defence. The graded work is always the defence — here, rejecting a certificate that shouldn't be trusted.
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Rung 1 — validate a certificate chain of trust
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Rung 2 — diagnose why a chain failed
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Later in PKI & Chains of Trust
This module unlocks