crossdomain.xml policy files

I hadn't even heard of this until tailing some apache logs turned up several dropped requests for a file called crossdomain.xml. With the advent of Flash Version 7, Macromedia introduced policy files that govern which domains a Flash movie is allowed to access data from. Without a file called crossdomain.xml file living in the root directory of your website, Flash Player 7 will display a warning dialog to appear when using Flash Player 6 and cause data loading to fail in Flash Player 7 format .swf files. Interestingly enough, these requests coincided with changing our source paths from relative to absolute. There are even more security enhancments in the latest version 8, Deneb Meketa explains further.

An example crossdomain.xml file:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<cross-domain-policy>
	<allow-access-from domain="10.55.0.69" secure="false"/>
	<allow-access-from domain="http://tcmacdonald.com" secure="false"/>
</cross-domain-policy>