How-To Secure Desktop Application To Web Service Calls

How can i secure Web Service calls from a desktop application (winform) ?

I first think about pass login/password to each web services m开发者_如何学编程ethods and then check from my database of user is authorized, but i'm looking for a better way to secure that.

Thanks.

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If your web service is written in WCF there are lots of security scenarios already built-in and which can be manipulated as easy as web.config settings.