http-stats:
HTTP/1.1 Keep-Alive header field

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

This field is probably a misinterpretation of the standard Connection header field.
"keep-alive" is a possible value for the Connection header field, along with "close" and others.
Is is not intended to be used as a field name. (it is actually a field value)
This field is not supported by any know client.


Common Keep-Alive header values:

The non-standard "Keep-Alive" 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 Keep-Alive web server response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Content-Length: 4913
Keep-Alive: timeout=15, max=100
Date: Fri, 30 Jul 2010 16:59:10 +0000

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

Other common HTTP headers

Other less common headers