Networking for Backend Engineers — Resources

Knowledge

Book: everything curl — Daniel Stenberg Free book by curl's author; the Verbose chapter decodes curl -v line by line, and Exit codes maps 6/7/28/35/56 to failure signatures (Unit 2). Use for: anything curl shows or does — verbose output, exit codes, timings, TLS options.
Book: High Performance Browser Networking — Ilya Grigorik (free online) Rigorous but readable coverage of latency, TCP, TLS, HTTP/1.1–HTTP/2; the Building Blocks of TCP chapter covers the handshake and lifecycle at debugging depth (Unit 2). Use for: the "why" behind RTT, handshakes, and connection reuse (Units 2, 5, 9, 13).
Docs: MDN — HTTP The reference for HTTP semantics: methods, status codes, headers, caching, CORS. Use for: Units 4, 5, 8 — cite it instead of guessing header behavior.
Article: "A Question of Timing" — Cloudflare blog The canonical walkthrough of curl -w timing variables and what each phase contains. Use for: latency decomposition (Units 1, 5, 9).
Article: "How to use dig" — Julia Evans Practitioner-grade dig tutorial: querying specific resolvers, reading answers, tracing. Use for: Unit 3 and the ladder's rung 1.
Zine: Networking! ACK! — Julia Evans (wizardzines, paid) One-page-per-tool debugging zine (ping, dig, nc, curl, tcpdump). Use for: a friendly second angle on any tool that isn't clicking.

Server Fault High-signal Q&A for sysadmin/networking problems; strong moderation. Use for: sanity-checking a diagnosis writeup, searching prior incidents by symptom.
r/devops Practitioner discussion of infra/debugging war stories. Use for: how real teams structure triage and on-call habits.

No single high-trust source for the full "A can't reach B" triage ladder — it's assembled across the sources above; the course's own reference/triage-ladder.md is the compressed version.
tcpdump: need a vetted beginner-safe primer before Unit 6 (candidates: Julia Evans' tcpdump material, man page EXAMPLES section).