Recommendation ITU-T X.1144 (2013) develops extensible access control markup language (XACML 3.0) which is an updated version of Recommendation ITU-T X.1142 (which is equivalent to OASIS XACML 2.0 (06/2006)). Revised Recommendation ITU-T X.1144 (2024) defines core XACML including syntax of the language, models, context with policy language model, syntax and processing rules. This Recommendation is technically equivalent and compatible with the OASIS XACML 3.1 standard.