How does facebook comments plugin works?

Question

I would like to understand how the facebook comment plugin, that is inserted inside a web page, using a javascript script and a div tag, works.

If I try to guess (and using firebug), the javascript part loads an iframe that is inserted inside the div part.

My problem, is that everybody can put a comment feed that is not necessarily ralative to the web page content! Suggest I'm example.com, how can I be sure that example.org is not using my example.com facebook comments?

Does Disqus works similarily?

Thanks in advance.

Answer 1

在IFRAME中加载的facebook网址可以访问REFERRER URL（在这种情况下是加载页面）并使用它来检查域。