In an exemplary embodiment, the rights expressions with the same canonical form can be configured as logical equivalents using any suitable algorithm, for example, such as the algorithm described in the Canonical XML Version 1.0 from the World Wide Web Consortium (W3C), W3C Recommendation 15 Mar. 2001, available on the World Wide Web (WWW) at <http://www.w3.org/TR/2001 /REC-xml-cl4n-20010315>, inc