1. 3.1 CDNhistorical

    English translation of the original VNote “CDN”, preserving its structure and examples.

  2. 3.2 DNShistorical

    What DNS is, why it is needed, the DNS resolution process, DNS hijacking, and intelligent DNS resolution.

  3. 1.8 TCP TIME_WAIThistorical

    Historical notes on TCP TIME_WAIT, why it exists, why it lasts 2MSL, and the high-concurrency short-connection problem.

  4. 1.9 UDPhistorical

    What UDP is and its connectionless, unreliable, message-oriented characteristics.

  5. 1.10 Transport Layerhistorical

    Transport-layer overview linking the original TCP and UDP notes.

  6. 2.4 Fiddlerhistorical

    Historical notes on Fiddler, its interface, HTTPS/proxy settings, filters, and Android packet capture.

  7. 2.5 HTTP KeepAlivehistorical

    Historical notes on HTTP KeepAlive, TCP connection reuse, and the difference from TCP keepalive.

  8. 2.6 HTTPhistorical

    Historical HTTP overview covering messages, URLs, methods, status codes, versions, caching, cross-origin access, push, cookies, HTTPS, RESTful, and Fiddler.

  9. 2.7 HTTPShistorical

    Historical notes on HTTPS, its simplified handshake model, encryption, certificates, and packet capture.

  10. 2.8 HTTP Methodshistorical

    Historical notes on HTTP methods and properties such as safety, idempotency, and cacheability.