Subject: Proxies and Real IP addresses...

From: "Remi B. Smith" <[email-masked]>
Date: Wed, 18 Dec 2002 14:02:33 -0500 (EST)

Hi, I recently found the following message posted on here, its from 2001:

>hi 
>    i m writing a small webserver. i just want to know that when the client connects to the webserver through proxy
>th webserver gets the  proxy ip. is there any way by which i can get the actual client ip.
>
>Ajay

The answers pretty much were all no.  My question is about the same.  Has a way been found around the IP masquerading of proxies?  Would something as simple as a hidden field in a form that contains the IP from the remote computer make it through the proxy?  Or is there a much more complex solution?

Thanks

Remi

---

From: Alex Rousskov <[email-masked]>
Date: Wed, 18 Dec 2002 12:49:28 -0700 (MST)

On Wed, 18 Dec 2002, Remi B. Smith wrote:

> Would something as simple as a hidden field in a form that contains the IP
> from the remote computer make it through the proxy?

Yes, in general. However, not all remote computers have a (single,
unique, static) IP address. Some remote computers have no IP address.
Not all browsers will let you access client IP address. Not all users
are humans using browsers.

> Or is there a much more complex solution?

IMHO, the _correct_ solution is (usually) to avoid relying on IP-level
information because it may not be available, is not reliable, easily
spoofed, and has virtually nothing to do with HTTP or even the Web.

Alex.

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