应用层

HTTP/1.0 short connections and statelessness, HTTP/1.1 persistent connections and pipelining, and HTTP/2 binary framing and header compression.

What WebSocket is, why it is needed, its role, its relationship with HTTP, and the WebSocket frame format.

English translation of the original VNote “HTTP Status Codes”, preserving the original list of status codes and explanations.

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

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

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

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

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

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

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

Historical notes on browser HTTP caching, strong cache, negotiated cache, Expires, Cache-Control, Last-Modified, and ETag.

A short historical note on HTTP connection, read, and write timeouts.

Historical notes on RESTful architecture, resources, representations, state transfer, and perceived limitations.

A short historical note on why URL encoding is needed and how URLs are encoded.

Historical notes on the cookie/session mechanism and a simple comparison.

Historical notes on the sequence of events after entering a URL in a browser.

Historical notes on the browser same-origin policy, cross-origin restrictions, and CORS.

Application-layer overview linking the original HTTP and DNS notes.