Installation and Upgrade > Advanced Deployment Considerations > Authentication > Configuring an Alternative Authentication in Windchill > Form-based Authentication
  
Form-based Authentication
Before you can configure Windchill for form-based authentication, you must select a form-based authentication solution and make any required modifications for its use with Windchill. There are a variety of form-based authentication solutions ranging from SiteMinder to the form-based authentication support built into the embedded servlet engine. Although the individual configuration details are specific to the solution and are not documented here, the following sections include Windchill details that are important to understand. For details on setting up a form-based authentication solution, see the documentation provided by the solution.
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Any changes you make to files that are delivered with your Windchill application should be treated as customized files that can be overwritten by PTC during any maintenance installation process. Ensure that customized files are backed up as described in Managing Customizations.
Since the log off capability that is available with form-based authentication is not available with the default basic authentication and, therefore, is not described in detail in end user documentation, users may not be aware of the ability to log off. When rolling out a Windchill environment in which form-based authentication is enabled, alert users as to how they can log off. If you change the default log off behavior for the Log Off menu option (which is described later in this section), be sure to also communicate the new behavior to users.