How do I pass existing login from one WCF RIA Service to another one?

I have two different Silverlight RIA Services apps running on the same server. They both use the same username/password/membership/cookiename for authentication. All of our WCF methods has RequiresAuthetication attributes. Now has come the time where we need to call one WCF service from another WCF Service.

Other than combining the two apps in one, I'm sure we cannot go around storing username/passwords and then passing them around, so what's best practice for this? How do I pass the username/password (or some other object?) around to pass credentials开发者_高级运维 and consume that other WCF service?

Thanks!

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RIA Services applications use ASP.NET application services by default. If you want credentials from one application to be valid for the other, you can use the same application name (Membership.ApplicationName) for both applications.