Why Web.config does not have tags, but the Membership page wroks fine?

 Followed the msdn Walkthrough, http://msdn.microsoft.com/en-us/library/879kf95c.aspx
I have created a Membership website with forms authentication.  The web pages seemed to
be working very well.  Instead of the SQL Server 2005 Express, I used our SQL Server 2005
at the IIS server.  From the database, I can see the aspnet_Membership and aspnet_Users
tables.

However, the Walkthrough did not show how to configure the Membership Provider by adding
the <membership> section to the web.config file, therefore my web.config does not have <membership>
tags.  My question is why my web.config does not have <membership> tags, but the Membership
web page still worked very well? 


 
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