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- Grouper built-in basic authentication
- Grouper LDAP authentication
- Tomcat authentication
- Apache authentication
- Kerberos user/pass
- Custom authentication
- Rampart (on top of something else)
- SSL certificates. There is no documentation on this. Do this with Apache or Tomcat and pass in the REMOTE_USER.
- other? if you can get a REMOTE user _USER via apache or tomcat plugin or filter, it will work with Grouper WS
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