Ask HN: Retrieving and processing offsite pages on a web browser

Hello

I am wondering how, if it is possible at all, how a browser visiting one site (say a.com) could be made retrieving and processing pages from multiple websites (b.com, c.com, d.com..), sending back some strings to a.com?

The goal is to compare how fast/different are the various b.com, c.com, d.com websites based on a.com visitors connection, with the information being sent to a.com

The result would be a survey updated with data from every new visitor.

So far, the javascript options I've tried are not possible due to cross site scripting protection on the browser. a.com javascript can only be made loading a.com own pages.

Loading offsites pages requires running some kind of proxy on a.com to load them through it, which defeats the purpose - comparing the other websites from different connections.

There is no need to run scripts from the other websites - all the scripts will be provided by a.com. However, they need to have b.com (etc.) html code loaded to check how fast it does, how different it is from another visitor, etc. with chunks being sent back to a.com

hn at guylhem dot net