An application's trust level determines the permissions it is granted by CAS policy. This determines the extent to which the application can access secure resources and perform privileged operations.
Use the <trust> element to configure the application's trust level. By default, the configuration level is set to Full, as shown below:
<!-- level="[FullHighMediumLowMinimal]" --> <trust level="Full" originUrl=""/>
This means that the application is granted full and unrestricted CAS permissions. With this configuration, the success or failure of any resource access performed by the application depends only on operating system security.
If you change the trust level to a level other than Full, you may break existing ASP.NET Web applications depending on the types of resources they access and the operations they perform. Applications should be thoroughly tested at each trust level.
For more information about building partial-trust Web applications that use CAS, see Chapter 9, "Using Code Access Security with ASP.NET." For more information about using trust levels to provide application isolation, see Chapter 20, "Hosting Multiple ASP.NET Web Applications."