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Networking for Interviews

Interview-focused networking depth for senior+ loops — the layered request path, TCP/UDP, DNS, TLS, HTTP evolution through HTTP/3, load balancing, and CDN caching. Curated readings with time estimates, not a networking PhD. Skips ops-heavy topics (kernel I/O, Wireshark certification, distributed tracing) that rarely move interview verdicts.

Time budget: ≈14h

How to use this reference

  • Work through topics top to bottom — HTTP/2 and HTTP/3 assume TCP and TLS; CDN caching assumes HTTP headers from earlier topics.
  • Each subtopic is a brief overview plus 2–4 hand-picked readings — one Kurose section and one practitioner article where possible. Read for interview fluency, not cover-to-cover.
  • Optional hands-on tasks use curl, dig, and openssl — the tools you should be able to describe in a verbal round.
  • This track is sized for interview ROI: if a topic rarely appears in senior loops (ARP internals, epoll tuning, Jaeger architecture), it's not here. Continue with Communication & Data Transfer for application-layer APIs, RPC, and bulk transfer patterns.

The Reference

  1. 1

    The layered mental model and end-to-end request path every other topic builds on.

    1. 1.1Layers, Encapsulation & the Request Path1/520m
  2. 2

    Ports, reliability, and the congestion behavior behind every API call.

    1. 2.1UDP & When to Use It2/515m
    2. 2.2TCP Handshake, Reliability & Congestion3/525m
  3. 3

    How hostnames become IPs — and why resolution failures look like "the service is down."

    1. 3.1Resolution, Records & Caching2/520m
  4. 4

    Encrypting the wire — handshakes, certificates, and the trade-offs interviewers still ask about.

    1. 4.1Handshake, Certificates & TLS 1.33/525m
  5. 5

    How the application layer chased lower latency — and why each version still matters in interviews.

    1. 5.1HTTP/1.1, HTTP/2 & HTTP/3 Compared3/530m
  6. 6

    How traffic reaches your service — and how edge caching shapes latency.

    1. 6.1L4 vs L7 Load Balancing3/520m
    2. 6.2Reverse Proxies, Connection Pooling & CDN3/525m
  7. 7

    The minimum command-line fluency for verbal rounds and live troubleshooting.

    1. 7.1curl, dig & Basic Diagnostics2/515m