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<h1>Help</h1>
<p>
<h3>Basic authentication</h3> is the default and can be supported effectively without even setting <b>sso.type</b>
Just by providing credentials for the domain. The credentials will not be sent preemptively, 
but if a 401 request is returned for Basic authentication, it will be handled properly.   
Tis is equivalent to setting sso.type=basic (or sso.type=html (old - now deprecated in favor of calling it <b>basic</b>).
if you set sso.type=basic.preemptive, it will send the credentials preemptively.
</p>
<br/>
<p>
<h3>URL authentication</h3> (query args) is supported as <b>sso.type=url</b> or <b>sso.type=url.base64</b>.
By definition, this type of authentication is <quote>preemptive</quote>, so no distinction is made 
there.   
</p>
<br/>
<p>
<h3>Form-authentication</h3> is supported with <b>sso.type=form</b> (which is equivalent to sso.type=form.post - you can also specify sso.type=form.get, 
if GET protocol is used on the login form). This form also requires a bunch of other data 
( e.g. the action URL, other args, names of the fields for credentials, etc.).   
All of this is in an example that is in the demo portlet.xml.   
Form-based authentication is also considred "preemptive", in that it authenticates before any other 
content is read. However, it only does it once.  If it succeeds, all should be well.
If it fails, the user will have to login by hand (since the initial content URL will 
cause a redirect to the login page).
</p>
<br/>