Extended Queueing Networks Modeling and Markup Language is a formalism (abstract + concrete) syntaxes + XML-based interchange format for high level interoperability between analysis and simulation tools, Automatic generated IDEs + code based on MDE.
The eXtensible Access Control Markup Language (XACML) allows for generic access control policies in XML format. pam_xacml provides XACML support for many existing pam enabled applications (no changes to the code required).