Responsible editors: P. A. Bonatti

This report’s main goal is specifying syntax and semantics of the core of Protune, the policy language and metalanguage of REWERSE. The language can specify access control policies, privacy policies, reputation-based policies, provisional policies, and a class of business rules. The document also specifies the architecture of a distributed policy-based system, together with a suite of policy-related services. It introduces some policy filtering methodologies needed for negotiation semantics and query processing, and proves their properties in terms of information preservation or loss. We illustrate the language by means of numerous examples and outline a refined use case list for verbalization (i.e., formulation in controlled natural language) in the form of a representative list of sample policies