 As a standard RBAC system, PERMIS's main entities are 

The PERMIS policy is eXtensible Markup Language (XML)-based and has rules for user-role assignments and role-privilege assignments, the latter containing optional obligations that are returned to the application when a user is granted access to a resource.A PERMIS policy can be stored as either a simple text XML file, or as an attribute within a signed X.509 attribute certificate to provide integrity protection and tampering detection.User roles and attributes may be held in secure signed X.509 attributes certificates, and stored in Lightweight Directory Access Protocol (LDAP) directories or Web-based Distributed Authoring and Versioning (WebDAV) repositories, or they may be created on demand as Security Assertion Markup Language (SAML) attribute assertions.