CSE38 · CSE foundations & data structures
DNS, HTTP & TLS Explorer
Follow one web request: DNS finds the address, TLS sets up a secure channel and HTTP carries the request.
🎯 You will learn to
- Trace a name lookup
- Read a TLS handshake summary
- Read HTTP status codes
🧪 Live environment
Runs entirely in your browser: nothing is installed, no real cloud account is used and your code is never sent to our server.
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✅ Steps & checkpoints
🗺️ One request, three protocols
DNS turns the name into an address, TLS proves the server and agrees keys, then HTTP carries the request inside the encrypted channel.
The 2D diagram shows the exact flow, ports and trust boundaries. The 3D scene is a concept view of the same parts; packets travel along the same arrows.
🤔 Think about it
Why does the browser refuse a certificate for the wrong name?
🛡️ Safety & cost
Simulations and in-browser runtimes only.
🧹 Cleanup
Nothing to clean up.
📚 Reference documents
- RFC 1034: Domain names, concepts and facilities · IETF
- RFC 8446: TLS 1.3 · IETF
- An overview of HTTP · MDN
- Introduction to Algorithms (6.006) · MIT OpenCourseWare
- The Python Tutorial · Python
- SQL as understood by SQLite · SQLite
- Linux man pages · man7.org
Official sources, checked on 5 Nov 2026. Cloud services change often; check the official page before relying on a feature. All references