I'm going to try to clarify what I think the question is before attempting to answer it:

There are four parties

You want to know when a someone visits your page on site X.

Since you have no access to the logs of X, cannot add JavaScript to X, cannot run server side scripting on X, then the only way to get the information is to cause the visitor to make a request to something on Y.

About the only way to do this is to include an image on that page which is loaded off server Y. This isn't entirely reliable as users can disable iamges, disable images from remote sites, etc, etc

Without putting a seperate URL to the image for each id on X you can't reliably know the ID.

HTTP provides a referer header, this will tell you the URL that referred the user agent to another URL (i.e. the URL of the page that linked to the image).

The referer header is, however, optional and many personal firewall products munge it.

There is no reliable way to do what you want.

In reply to Re: capture data - html by dorward
in thread capture data - html by kevyt

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