[Show abstract][Hide abstract] ABSTRACT: Complex services in service-oriented architectures such as the grid typically require to be configured in multiple ways that cannot be anticipated by service designers; we illustrate this requirement by studying the myGrid registry, a grid registry capable of supporting annotations of service descriptions by third-party users. Instead, services have to be conceived so that they can be configured at deployment and run time. We argue that KAoS is a powerful and flexible language that can help define such configurations. Using our registry case study, we examine the requirements that the definition of such complex configurations brings on policy languages and explain how they can be satisfied. Specifically, we use role-value maps to express constraints between property values; we introduce a notion of PolicySet with associated parameters that support constraints within a well defined scope; finally, we define a notion of context that allows us to refer to property values that were extant in past execution environments. Essentially, these concepts allow us to add constraints to values in policy definitions, to organise policies in coherent and structure blocks, and to refer to the execution history. The paper discusses these concepts and how they are implemented in a binding of the KAoS policy language to the myGrid registry.
Cluster Computing and the Grid, 2005. CCGrid 2005. IEEE International Symposium on; 06/2005
[Show abstract][Hide abstract] ABSTRACT: We describe our initial implementation of the KAoS policy and domain services. While primarily oriented to the dynamic and complex requirements of software agent applications, the services are also being adapted to general-purpose grid computing and Web services environments as well. The KAoS services rely on a DAML description-logic-based ontology of the computational environment, application context, and the policies themselves that enables runtime extensibility and adaptability of the system, as well as the ability to analyze policies relating to entities described at different levels of abstraction.
Policies for Distributed Systems and Networks, 2003. Proceedings. POLICY 2003. IEEE 4th International Workshop on; 07/2003
[Show abstract][Hide abstract] ABSTRACT: To increase the assurance with which agents can be deployed in operational settings, we have been developing the KAoS policy and domain services. In conjunction with Nomads strong mobility and safe execution features, KAoS services and tools allow for the specification, management, conflict resolution, and enforcement of DAML-based policies within the specific contexts established by complex organizational structures. In this paper, we will discuss results, issues, and lessons learned in the development of these representations, tools, and services and their use in military and space applications Keywords social order, conventions, norms, social control; cultural norms and institutions, ontologies for agents and social modeling; ontologies in agent-based information systems and knowledge management, DAML, policy, domains, KAoS, Nomads, human-agent teamwork, adjustable autonomy, coalition, augmented cognition, cognitive prosthesis 1.
[Show abstract][Hide abstract] ABSTRACT: This paper introduces a version of KAoS Semantic Policy and Domain Services that has been developed to support Web Services-based (i.e., OGSA-compliant) Grid Computing Architectures. While initially oriented to the dynamic and complex requirements of software agent applications, KAoS services are now being extended to work equally well with both agent and non-agent clients on a variety of more general distributed computing platforms. The OGSA-compliant version of KAoS services allows fine-grained policy-based management of registered Grid services as well as opening additional opportunities for the use of agents on the grid.
[Show abstract][Hide abstract] ABSTRACT: Description-logic-based knowledge representations and reasoning methods are being used increasingly as the basis for semantically-rich software services. Using such representations and reasoning methods in comprehensive applications is among one of the best ways to identify and understand gaps and limitations. KAoS domain and policy services, which rely extensively on a DAML-based ontology, are used as a case study to investigate an in-depth application of DAML. In this context, we explore the current limitations of DAML semantics. We also describe our observations about the place of ontology description at the heart of KAoS services, and outline requirements for effective interfaces for humans and for translation to and from efficient programming environments. Next, we present the problems implicated by development of ontology descriptions in a distributed dynamic environment. Finally, we assess the utility and maturity of available tools such as editors, programming libraries and inference engines. An application of KAoS to provide policies for DAML-S Web services concludes the paper.
[Show abstract][Hide abstract] ABSTRACT: This paper summarizes our efforts to bring together and extend the best in current theory and technologies for teamwork-centered autonomy for space applications. Traditional planning technologies at the foundation of intelligent robotic systems typically take an autonomy-centered approach, with representations, mechanisms, and algorithms that have been designed to ingest a set of goals and output a complete plan in the most efficient and sound fashion possible. A teamwork-centered autonomy approach, on the other hand, takes as a beginning premise that people are working in parallel alongside autonomous systems, and hence adopts the stance that the processes of understanding, problem solving, and task execution are necessarily incremental, subject to negotiation, and forever tentative. Thus, a successful approach to teamwork-centered autonomy will require that every element of the autonomous system be designed to facilitate the kind of give-and-take that quintessentially characterizes natural and effective teamwork among groups of people. We briefly describe the major components of this approach and current efforts to apply and evaluate its utility from both human-centered and cost-benefit perspectives.