Question

I have a Silverlight application that cannot login when it installed in a different IP Segment to the server. (The client is in 192.168.77.xx and the server is in 192.168.40.xx).

When the client is on the same segment it runs smoothly.

The client can ping, telnet and remote-desktop the server. It also can login other applications from the server, but it cannot login into my Silverlight application.

Does anybody know how to run Silverlight application with different IP Segments?

Answer 1

To prevent cross-site request forgery, Silverlight 4 (and later) allows only site-of-origin communication by default for all requests other than images and media. To enable a Silverlight control to access a service in another domain, the service must explicitly opt-in to allow cross-domain access.

So, you should place ClientAccessPolicy.xml or CrossDomain.xml at the root of web site where Silverlight application is hosted.

Here is sample of ClientAccessPolicy.xml (allows access from any other domain to all resources on the current domain):

<?xml version="1.0" encoding="utf-8"?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from http-request-headers="SOAPAction">
        <domain uri="*"/>
      </allow-from>
      <grant-to>
        <resource path="/" include-subpaths="true"/>
      </grant-to>
    </policy>
  </cross-domain-access>
</access-policy>

And here is sample of CrossDomain.xml:

<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
  <allow-http-request-headers-from domain="*" headers="SOAPAction,Content-Type"/>
</cross-domain-policy>

Read here about making a service available across domain boundaries.