Local Connection Conundrum

Hiya, I’m working on some banners and I would like to get them to interact with each other.
I am fine having them interact using Local Connection, the banners may not be running at the same time as some sites rotate their banners. This is fine as I can get the swfs to check if another one is running though a problem may arise if the user opens more than one web page.

Is there a way I can get a swf to check which web page it resides on or is there another way I can check to see that my two swf banners exist on the same web page?

Any suggestions much appreciated.