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The Browser Based Authentication mechanism is different in that it uses the browser's built-in functionality to authenticate a user to a web site. It is important to point out that the user's web browser fully participates in logging the user into the web site - this is a completely different approach to the Forms/SSL method. Since the browser knows it is logging the user into a remote web site, it can use a built-in dialog box to ask the user for their username and password. Here are the dialog boxes used by Internet Explorer 6.0 and FireFox 1.0:
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