Authentication methods: which one fits your need
What authentication means, then Basic, cookies, tokens, JWT, OAuth, OpenID Connect and SAML mapped to the need each serves, and the problem each one fixed.
More in the System design
- Core concepts in System Design
- SQL vs NoSQL: picking a database
- CAP theorem: when the network breaks, pick one
- Before message queues: why systems needed a mailbox
- Queues, pub/sub and logs: how they differ inside
- Case studies in System Design
- Who gets the last phone in a flash sale
- Which database for a food delivery app
- The cache expired and the database fell over
- A live final: scale before the toss
- An app like ChatGPT: the answer is written live
- A product Q&A box on sale day
- Tatkal at 10:00: one seat, sold in stretches
- A group chat: one register, many sockets
- Authentication in System Design
- JWT in System Design: Sessions, Revocation & Refresh
- The interview questions, answered
- Life of a session, step by step
- Anatomy of a JWT
- Forge lab: why verification must be strict
- JWT vs session
- The validation pipeline: where a bad request dies
- Revocation: the 12-minute problem
- Refresh tokens and rotation
- Logout in depth: one device, all devices, SSO
- What actually makes a JWT secure
- OAuth 2.0 and OIDC: how the token gets there
- Where the token lives on the client
- Microservices, keys, and trust boundaries
- Sender-constrained tokens: making a stolen token useless
- Authentication vs authorization middleware
- Failure explorer: what breaks when X fails
- Capacity planner: sessions vs JWT vs hybrid
- Edge cases catalog
- Test it, measure it, migrate to it
- Anti-patterns to reject in a design review
- Design checklist and cheat sheet
More courses
- Jobs, linked to lessons — Browse jobs where every requirement links to the chapter that teaches it. See how ready you are, how long the gap takes to close, and which listings look stale.
- Match a job post to courses — Paste a job post. Each skill is matched to a track here and put in learning order, foundations first.
- React from open source with patterns — Patterns extracted from Material UI, Radix, React Aria, React Hook Form, Redux Toolkit, TanStack, and Next.js — not slides about hooks.
- Database in depth — How a query becomes work. Indexes, isolation, locks, and the plans that explain why a page is slow — not an ORM tour.
- Microservices — Microservice patterns one diagram at a time: how to split a monolith, how services talk, and how data stays consistent without distributed transactions.
- Kafka — A beginner-to-senior path through event logs, reliable delivery, production operations, and disaster recovery.
- Frontend system design — How a UI is sliced when it is a product, not a page: ownership of state, cache, routes, and what happens when the network lies.
- TypeScript in depth — The type system as a design tool. Inference, narrowing, generics, and the errors that mean the model is wrong — not a catalog of utility types.
- CSS in depth — See the box, then the page. Visual chapters from the box model through Flexbox surprises, Grid, selectors, and units, then backgrounds, shapes, and visual effects, each with a playground.
- Accessibility — Foundations first (WCAG in plain words, semantic HTML, lists, alt text), then hands-on HTML labs, a full pass of WAI-ARIA 1.3, and a final fix-the-page challenge.
- Docker — What an image is, why layers cache, and how containers find each other on a network.
- Redis — Fifteen Redis patterns, one picture each: cache, session, lock, counter, rate limiter, queue, and when Redis is the wrong tool.