03. Availability, Consistency, and the CAP Theorem

Episode 3 of 34 | System Design: From Fundamentals to Interview Mastery Understand CAP through an original two-region reservation example. See the difference between linearizability and eventual convergence, why a timeout creates uncertainty, how quorum ownership affects booking correctness, and why browsing and reservations can legitimately choose different behavior during a partition. Original script, worked examples, diagrams and animation. Adapted educational presentation; no endorsement implied. Voice generated locally with the speaker's authorization. Chapters 0:00 Welcome and what we will cover 0:11 One room, two regions, one difficult promise 1:25 What the three words mean 2:55 Why the disconnected region cannot know enough 4:09 A consistency-first reservation policy 5:32 An availability-first policy needs honest semantics 6:54 One product can choose different guarantees per operation 8:20 A replicated read is not automatically current 9:43 How to explain CAP without a memorized triangle 11:09 Recap, practice and thank you