HTTP Protocol

Links

• https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching
• https://book.varnish-software.com/4.0/chapters/HTTP.html

Response

• ETag - hash for resource
  • request If-None-Match = , response 304 (Not Modified)
• Cache-Control
  • no-store - don’t store anything in browser
  • no-cache - use ETag only
  • public - cache is allowed, private - disables CDN
  • max-age - reuse in seconds
  • Expires - deprecated

DNS

• dig abc.com +trace
• dig abs.com @ns30.domaincontrol.com