The UserIdentityToken structure used in the Server Service Set allows Clients to specify the identity of the user they are acting on behalf of. The exact mechanism used to identify users depends on the system configuration. The different types of identity tokens are based on the most common mechanisms that are used in systems today. Table 185 defines the current set of user identity tokens. The ExtensibleParameter type is defined in 7.17.

Table 185 – UserIdentityToken parameterTypeIds

Symbolic Id	Description
AnonymousIdentityToken	No user information is available.
UserNameIdentityToken	A user identified by user name and password.
X509IdentityToken	A user identified by an X.509 v3 Certificate.
IssuedIdentityToken	A user identified by a token issued by an external Authorization Service.