HTTP/1.1, HTTP/2 and HTTP/3

The idea

Three HTTP versions, one request: what changes on the wire from HTTP/1.1 to HTTP/2 and HTTP/3. The laptop fetches pages through homeRouter from webServer, which speaks all three on Port 443.

Steps

1. HTTP/2: the same request, in frames

   Text lines are slow for a machine to parse, so HTTP/2 sends the same request as binary frames over one TCP connection. Fetch the page over HTTP/2, then with nghttp, which prints what crosses the wire.

   laptop:~# curl -sv --http2 https://webServer.lab/
   laptop:~# nghttp -nv https://webServer.lab/

2. Six files: six connections, or one

   A page needs many files, and each new connection costs a handshake before its first byte. curl fetches six style sheets at once over HTTP/1.1 while the laptop counts new TCP connections. Then fetch the same six over HTTP/2.

   laptop:~# curl -s --http1.1 -Z -o '/tmp/#1.css' -w '%{http_version}\n' 'https://webServer.lab/assets/{1,2,3,4,5,6}.css'
   laptop:~# curl -s --http2 -Z -o '/tmp/#1.css' -w '%{http_version}\n' 'https://webServer.lab/assets/{1,2,3,4,5,6}.css'