What is the guest role within Tomcat - web.xml?

[Meinolf . Schulte-Doeinghaus]

Hi,
I have created a WebApplication with tomcat 3.2
and gave security rights to a directory called 'test'
to a special role admin. Within this directory I want 
to create a subdirectory called 'img' that could be
used by everyone. 

How do I implement this in the web.xml descriptor?
I tried to do the following, but the role NONE doesn't work
with tomcat. I also tried guest, everyone, default ...

Any suggestions?

Regards
Meinolf


----------- 
web.xml

<security-constraint>
<web-resource-collection>
<web-resource-name>/test/*</web-resource-name>
<url-pattern>/test/*</url-pattern>
</web-resource-collection>

<auth-constraint>
<role-name>admin</role-name>
</auth-constraint>
</security-constraint>


<security-constraint>
<web-resource-collection>
<web-resource-name>/test/img/*</web-resource-name>
<url-pattern>/test/img/*</url-pattern>
</web-resource-collection>

<auth-constraint>
<role-name>NONE</role-name>
</auth-constraint>
</security-constraint>


<login-config>
<auth-method>BASIC</auth-method>
<realm-name>Templates</realm-name>
</login-config>


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