Network Security Access Restrictions
Network Security Access Restrictions in Silverlight 2:
1) When a socket request is made to the site (cross-domain or site of origin), the Silverlight 2 runtime opens a connection using TCP to a well-known port (port 943) on the target site. Then the runtime sends a special string <policy-file-request/> to the server to request a Silverlight policy file. The Silverlight 2 runtime then waits to receive a reply from the target site that contains a Silverlight policy file. The policy file retrieved will have to grant permission to have a connection to the target host opened.
A simple FluorineFx Silverlight Policy Server is provided. The application comes with a clientaccesspolicy.xml file you can change accordingly (set the port number used):
...
<socket-resource port="4502-4534" protocol="tcp"/>
...
2) Port range that a Silverlight 2 network application is allowed to connect to must be within the range of 4502-4534
Flash Media Server must be configured to listen on the port that can be accessed from a Silverlight application.
Open the fms.ini file and change the entry ADAPTOR.HOSTPORT = :1935 (if previously used 1935) to ADAPTOR.HOSTPORT = :4502
For details on Network Security Access Restrictions please read Network Security Access Restrictions in Silverlight 2 in the MSDN library