Flash Player 6.
System.security.allowDomain(domain1, domain2, ... domainN)
Method; allows movies in the identified domains to access objects and variables in the movie that calls the allowDomain() method.
The domains can be formatted in the following ways:
domain.com, http://domain.com
or
http://IPaddress
<http://www.macromedia.com/MovieA.swf> loads <http://www.shockwave.com/MovieB.swf>. MovieA.swf contains the command System.security.allowDomain("shockwave.com") . Therefore, MovieB.swf will be able to access the objects and variables of MovieA.swf.