How to implement multiple challenge questions in password recovery control in asp .net?
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I am looking to implement multiple challenge questions into the password recovery control in asp .net. The default Membership control accommodates only one challenge question.   

Its been suggested that one way to implement the multiple questions to the control is to create my own Membership provider. Although, to me, it seems like an easier approach if I just handle the challenge question part outside of the the password recovery control. Then, if the user answers the challenge questions successfully, the response will be tied in to  existing change password method to allow him/her to enter a new password. 

Here are my questions:  

 - What are the drawbacks to this approach?    
 - Why would I need to create a new Membership provider?    
 - When would I need to create a
   separate Membership provider?