Axis-Aligned Semantics for ODRL: Resolving Dimensional Ambiguity in Policy Constraints

arXiv (Cornell University)

Abstract

The Open Digital Rights Language (ODRL) represents policy constraints as triples of a left operand, an operator, and a value. Several spatial operands, however, range over multi-axis domains such as width, height, and depth, while the constraint syntax provides no explicit axis identity. As a result, policy engines cannot determine whether multiple constraints apply to the same axis or different ones, making conflict detection unsound or incomplete. We resolve this ambiguity by axis decomposition, replacing multi-axis operands with axis-specific scalar operands over totally ordered domains. Each constraint then denotes an interval per axis and each policy an axis-aligned box, reducing conflict detection to box comparison. We define a three-valued semantics (Conflict, Compatible, Unknown), prove the decomposition sound and backward compatible with ODRL, instantiate it as ODRL Axis-Aligned Profile (OAAP), and validate it on a benchmark of 256 ODRL policy problems, each expressed in Turtle and compiled to first-order (TPTP) and SMT-LIB form, using Vampire, E, Z3, and cvc5.

Authors 8

1. Daham Mohammed Mustafa Aachen

   Fraunhofer Institute for Applied Information Technology · RWTH Aachen University

   Affiliation as printed

   Fraunhofer FIT

   RWTH Aachen University

2. Diego Collarana

   Fraunhofer Institute for Applied Information Technology

   Affiliation as printed

   Fraunhofer FIT

3. Sabrina Kirrane
4. Christoph Lange
5. Christoph Quix Aachen

   Fraunhofer Institute for Applied Information Technology · RWTH Aachen University

   Affiliation as printed

   Fraunhofer FIT

   RWTH Aachen University

6. Rafiqul Haque

   Ollscoil na Gaillimhe – University of Galway

   Affiliation as printed

   University of Galway

7. Yixin Peng Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University

8. Stefan Decker Aachen

   Fraunhofer Institute for Applied Information Technology · RWTH Aachen University

   Affiliation as printed

   Fraunhofer FIT

   RWTH Aachen University