Applying KAoS Services to Ensure Policy Compliance for Semantic Web Services Workflow Composition and Enactment

Abstract

In this paper we describe our experience in applying KAoS services to ensure policy compliance for Semantic Web Services workflow composition and enactment. We are developing these capabilities within the context of two applications: Coalition Search and Rescue (CoSAR-TS) and Semantic Firewall (SFW). We describe how this work has uncovered requirements for increasing the expressivity of policy beyond what can be done with description logic (e.g., role-value-maps), and how we are extending our representation and reasoning mechanisms in a carefully controlled manner to that end. Since KAoS employs OWL for policy representation, it fits naturally with the use of OWL-S workflow descriptions generated by the AIAI I-X planning system in the CoSAR-TS application. The advanced reasoning mechanisms of KAoS are based on the JTP inference engine and enable the analysis of classes and instances of processes from a policy perspective. As the result of analysis, KAoS concludes whether a particular workflow step is allowed by policy and whether the performance of this step would incur additional policy-generated obligations. Issues in the representation of processes within OWL-S are described. Besides what is done during workflow composition, aspects of policy compliance can be checked at runtime when a workflow is enacted. We illustrate these capabilities through an example where policies control runtime queries and return results from the CMU Semantic Matchmaker. Finally, we outline plans for future work.

Supporting Semi-automated Compliance Control by a System Design Based on the Concept of Separation of Concerns

“…Thus, even with a compliant policy an incompliant transmission might be allowed and will stay undetected if decision or enforcement of the policy fails. If a security system has complete and audit proof logging, they can be extended by compliance checks [Us04]. For retrieving data, these approaches are very similar to our approach.…”

Access control and the Resource Description Framework: A survey

“…As both DAML and OWL are based on description logic, using the KAoS language it is possible to define class and property hierarchies, along with inference rules. Although KAoS was originally designed to enable interoperability between complex web agents (software that acts on behalf of humans) [12,88], it was later applied to web services [96,95,94,97] and grid computing [45,96].…”

A Survey of Policy-Based Management Approaches for Service Oriented Systems

“…An advantage of description logic is that it can be utilized in automatic derivation of policy for a service composition from those of individual services and vice versa using KAoS's policy reasoning engine. Also, there have been initial efforts in KAoS to support automatic policy analysis and enforcement for workflow [29].…”