on 5/5/01 9:24 PM, Anh Tu Vu at [EMAIL PROTECTED] wrote:
> telnet to port 80 of a site and use GET / HTTP/1.0 , i get a different web
> page from using IE to get to that site. Did the site use a proxy server to
> analyze HTTP header and return a page upon the header ? Which
> NAT/Proxy/Firewall scheme was probably used ?
This site is most probably using Name based virtual services services that
are HTTP/1.1 spec only, binding multiple sites to a single IP.
The HTTP 1.1 RFCs are available at many places;
http://www.ics.uci.edu/pub/ietf/http/rfc2616.txt is just an example of one.
The statements from the RFC below illustrate my thoughts, the proxy data is
here just since it is useful >;):
[snippage]
The absoluteURI form is REQUIRED when the request is being made to a
proxy. The proxy is requested to forward the request or service it
from a valid cache, and return the response. Note that the proxy MAY
forward the request on to another proxy or directly to the server
specified by the absoluteURI. In order to avoid request loops, a
proxy MUST be able to recognize all of its server names, including
any aliases, local variations, and the numeric IP address. An example
Request-Line would be:
GET http://www.w3.org/pub/WWW/TheProject.html HTTP/1.1
To allow for transition to absoluteURIs in all requests in future
versions of HTTP, all HTTP/1.1 servers MUST accept the absoluteURI
form in requests, even though HTTP/1.1 clients will only generate
them in requests to proxies.
The authority form is only used by the CONNECT method (section 9.9).
The most common form of Request-URI is that used to identify a
resource on an origin server or gateway. In this case the absolute
path of the URI MUST be transmitted (see section 3.2.1, abs_path) as
the Request-URI, and the network location of the URI (authority) MUST
be transmitted in a Host header field. For example, a client wishing
to retrieve the resource above directly from the origin server would
create a TCP connection to port 80 of the host "www.w3.org" and send
the lines:
GET /pub/WWW/TheProject.html HTTP/1.1
Host: www.w3.org
followed by the remainder of the Request. Note that the absolute path
cannot be empty; if none is present in the original URI, it MUST be
given as "/" (the server root).
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