http-stats:
HTTP/1.1 Host header field

The Host field is NOT a standard HTTP header field and may not be supported by all clients.

"Host" is a valid Request Header Field but should not be used as a Response Header Field.

That is, this header is valid when send from the client in a request to the server but non the other way around, when the server answers to the client query.

Probably, programmers confused this field with the Location header, which is intended to give destination information to the client (e.g. redirect destination).

No known clients are currently supporting this header field.


Common Host header values:

The non-standard "Host" header is only sent by:

NOTE: this header may be sent directly by the server software or from some third party application running on that server.

Sample Host web server response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Content-Length: 2881
Host: 124.109.178.140
Date: Fri, 30 Jul 2010 16:55:20 +0000

<!DOCTYPE html PUBLIC "-//W3C//DTD ...
...
...

Other common HTTP headers

Other less common headers