A Formalization of Distributed Authorization with Delegation

Abstract

Trust management is a promising approach for the authorization in distributed environment. There are two key issues for a trust management system: how to design high-level policy language and how to solve the compliance-checking problem [3,4]. We adopt this approach to deal with distributed authorization with delegation. In this paper, we propose an authorization language AL, a human-understandable high level language to specify various authorization policies. We define the semantics of AL through Answer Set Programming. Language AL has rich expressive power which can not only specify delegation, threshold structures addressed in previous approaches, but also represent structured resources and privileges, positive and negative authorizations, separation of duty, incomplete information reasoning and partial authorization and delegation. We also demonstrate the application of language AL through an authorization scenario.

Preface to an Introduction

“…The applicability of the knowledge representation and reasoning languages such as logic programming for the design and implementation of a distributed authorization system is becoming promising. Researchers use answer set programming to deal with many complex issues associated with the distributed authorization along with the trust management approach (Wang, 2005). Formal authorization language based on semantics of answer set programming can express non-monotonic delegation policies unambiguously.…”