Video lectures for Alfred Menezes's introductory course on real-world deployments of cryptography. Topics covered: Key management, FIDO, ePassports, code signing, certificates, public-key infrastructures, PKI, certification authority, CA, certificate format, certificate revocation, CA trust models Lecture playlist: Course web page: The slides are available on the course web page. Other cryptography courses: Slides 00:00 Introduction 00:44 Slide 18: Key management 01:11 Slide 19: Example: secure channels 02:35 Slide 20: Example: software updates 03:22 Slide 21: Three other examples 05:35 Slide 22: Methods for distributing public keys 07:08 Slide 23: Public-key infrastructures (PKI) 07:49 Slide 24: Components of a PKI 08:19 Slide 25: Certificate format 09:48 Slide 26: Certificate Authorities (CAs) 11:48 Slide 27: The certification process (1) 13:35 Slide 28: The certification process (2) 14:44 Slide 29: Certificate recovation 17:00 Slide 30: Certificate revocation lists (CRLs) 18:00 Slide 31: CA trust model: Single CA 18:41 Slide 32: CA trust model: Single-root hierarchical CA 20:00 Slide 33: CA trust model: Multi-root hierarchical CA 20:39 Slide 34: Example: ePassports PKI 22:13 Slide 35: PKI challenges