Something You Don't Know

Every software system that has ever mattered has wrestled with the same fundamental question: how do you know who you’re talking to? Something You Don't Know moves beyond the standard "how-to" of login boxes to explore the physics of identity and the architecture of trust. This book traces the evolution of authentication from Sumerian clay tablets to the birth of computer security at MIT, eventually landing on the cutting edge of modern engineering. 

You will move from the "original sin" of the stateless web to the implementation of phishing-resistant systems using passkeys and WebAuthn. Finally, you will look forward to the next decade of challenges, including agentic authentication for autonomous AI and the migration to Post-Quantum Cryptography using ML-KEM. Written for software engineers who build systems at scale, this is the definitive guide to getting identity right.