WCF Custom Authentication from Silverlight Application

I'm trying to create secure authentication for a silverlight application, but not sure where to start.

The application has several WCF Services that it connects to, I only want users that are logged in to be able to access these services.

All of the methods within the services take a user id as a parameter and only retrieve data valid for that user this user id.

I've tried following a few tutorials but most of the stuff I find is for RIA services which I开发者_开发问答'm not using.

Would anyone be able to suggest some sites / tutorials that I can read through.

Thanks

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It I remember correctly, last time I looked at Silverlight's implementation of WCF, it supports either Windows auth or username/password auth (in full-blown WCF you can do more intricate custom authentications).

(Edit: I don't think Silverlight includes wsHttpBinding, so my statement above about WIndows auth is probably wrong).

Does this help any? http://web-snippets.blogspot.com/2008/08/authentication-in-silverlight-using.html

Or this one: http://www.netfxharmonics.com/2008/11/Understanding-WCF-Services-in-Silverlight-2#WCFSilverlightAuthentication