I\'ve been using a custom membership provider for authentication in all my web form applications till now. I\'m about to start developing my first website using MVC. I\'m
If you have to ask, you shouldn't be writing your own provider. Doing security well is really hard. Doing it wrong is incredibly easy.
But the good news is that what you want is incredibly common, and there are tested, off-the-shelf tools which already do it. An example is Janrain. There are others, too. Use an existing, proven tool whenever possible.