HTTP headers | Via

The HTTP headers Via is used to inform the server of proxies through which the request was sent. The Via general is added by. It tacks the messages forwarded, request loops avoided, and identify the protocol capabilities of the sender. The header type of Via is the General type.

Syntax:

Via: [ <protocol-name> "/" ] <protocol-version> <host> [ ":" <port> ]

or

Via: [ <protocol-name> "/" ] <protocol-version> <pseudonym>

Directives: There are four directives accepted by HTTP headers Via.

  • <protocol-name>: It is an optional directive and used to define the protocols in headers like “HTTP”
  • <protocol-version>: This directive is used to define the version of the protocol.
  • <host> and <post>: This directive defines the public proxy URL and port.
  • <pseudonym>: This directives defines the name/alias of an internal proxy.

Example:

Via: HTTP/1.1 GWA
via: 1.1 2e9b3ee4d534903f433e1ed8ea30e57a.cloudfront.net (CloudFront)

To check this Via in action go to Inspect Element -> Network check the request header for Via like below, via is highlighted you can see.

Note: The HTTP headers via can be visible in the Response and Request both headers.

Supported Browsers: The browsers compatible with HTTP headers Via are listed below:

  • Google Chrome
  • Internet Explorer
  • Firefox
  • Safari
  • Opera