HTTP Upgrade Header - HTTP/2
Download List of All Websites using HTTP Upgrade Header - HTTP/2
The HTTP Upgrade mechanism is used to establish HTTP/2 starting from plain HTTP. The client starts an HTTP/1.1 connection and sends an Upgrade: h2c header. If the server supports HTTP/2, it replies with HTTP 101 Switching Protocol status code. The HTTP Upgrade mechanism is used only for cleartext HTTP2 (h2c). In the case of HTTP2 over TLS (h2), the ALPN TLS protocol extension is used instead.
Tags:
Must Revalidate HTTP Cache-Control
Download List of All Websites using Must Revalidate HTTP Cache-Control
Indicates that once a resource has become stale (e.g. max-age has expired), a cache must not use the response to satisfy subsequent requests for this resource without successful validation on the origin server.
Tags:
Cache-Control Header Max-Age
Download List of All Websites using Cache-Control Header Max-Age
Specifies the maximum amount of time a resource will be considered fresh. Contrary to Expires, this directive is relative to the time of the request. this website is having max-age=3 secs.
Tags:
Vary Header Accept-Encoding
Download List of All Websites using Vary Header Accept-Encoding
The Accept-Encoding request HTTP header advertises which content encoding, usually a compression algorithm, the client is able to understand. Using content negotiation, the server selects one of the proposals, uses it and informs the client of its choice with the Content-Encoding response header.
Tags:
Vary Header check for User-Agent
Download List of All Websites using Vary Header check for User-Agent
When using the Vary: User-Agent header, caching servers should consider the user agent when deciding whether to serve the page from cache
Tags:
Vary Header check for cookies
Download List of All Websites using Vary Header check for cookies
The Vary HTTP response header determines how to match future request headers to decide whether a cached response can be used rather than requesting a fresh one from the origin server. It is used by the server to indicate which headers it used when selecting a representation of a resource in a content negotiation algorithm.
Tags:
XFN 1.1
Download List of All Websites using XFN 1.1
XFN is a technical term that is an acronym that stands for “XHTML Friends Network.” This is primarily used by websites that want to create a series of referral links between other websites in order to boost SEO ratings.