-*- mode: outline; coding: utf-8 -*-

* Web server in Cygwin.

  $ setup -p apache2,lighttpd,dhttp

* Encoding HTTP data.

Starting with HTTP/1.1, web clients can indicate support for compression:

  Accept-Encoding: gzip, deflate

Web server notifies the web client of this via the Content-Encoding header in the response:

  Content-Encoding: gzip

* ETags.

Server respond:

  HTTP/1.1 200 OK
  Last-Modified: Tue, 12 Dec 2006 03:03:59 GMT
  ETag: "10c24bc-4ab-457e1c1f"
  Content-Length: 12195

Lately client send:

  GET /i/yahoo.gif HTTP/1.1
  Host: us.yimg.com
  If-Modified-Since: Tue, 12 Dec 2006 03:03:59 GMT
  If-None-Match: "10c24bc-4ab-457e1c1f"

and get respond:

  HTTP/1.1 304 Not Modified