Silverlight 2 tutorial (10): Silverlight 2.0 URL Access Policy

For security reasons and other security threats, such as passing cookies and allowing address redirection, Silverlight restricts cross-security region, cross-origin, and cross-Protocol URL access. For example, if your Silverlight program is embedded in a domain and you attempt to use a WebClient object to access files stored in another domain, the request will fail, in addition, this error prompt is not an accurate prompt for this error. If you want Cross-origin access, you need to configure files such as clientaccesspolicy. xml or crossdomain. xml.

The following table lists URL access rules in Silverlight 2.0:

	WebClient object	Media, images, ASX	XAML files and Font files	Streaming Media
Protocols allowed	HTTP and HTTPS	HTTP, HTTPS, FILE	HTTP, HTTPS, FILE	HTTP
Cross-protocol access	Not Allowed	Not Allowed	Not Allowed	Access from HTTPS is not allowed
Cross-Web domain access	Not Allowed	If it is not from HTTPS, allow	Not Allowed	Allow
Cross-security region access (Windows)	Not Allowed	Not Allowed	Not Allowed	Not Allowed
Cross-security region access (Macintosh)	Not Allowed	Allow	Not Allowed	Allow
Redirect allowed	Same Domain Allowed	Allow	Same Domain Allowed	Not Allowed