Date Added: Aug 2010
Policy analysis is one of the main focuses in the research of policy based security mechanisms for coalition environments. The authors have used abductive inference, a powerful reasoning tool, for centralised policy analysis under the formal policy framework they have developed for the ITA project. However, while considering a more dynamic and distributed coalition environment, assumptions for collecting all policies or domain knowledge for central computation are often not applicable, due to either confidentiality or efficiency. Therefore, distributed algorithms are needed for decentralised policy analysis. In addition, these algorithms have to be able to support constraint satisfaction, since policies often contain constraints over time as conditions.