Hyacinth S. Nwana

Software agents: an overview

Agent software is a rapidly developing area of research. However, the overuse of the word ‘agent’ has tended to mask the fact that, in reality, there is a truly heterogeneous body of research being carried out under this banner. This overview paper presents a typology of agents. Next, it places agents in context, defines them and then goes on, inter alia, to overview critically the rationales, hypotheses, goals, challenges and state-of-the-art demonstrators of the various agent types in our typology. Hence, it attempts to make explicit much of what is usually implicit in the agents literature. It also proceeds to overview some other general issues which pertain to all the types of agents in the typology. This paper largely reviews software agents, and it also contains some strong opinions that are not necessarily widely accepted by the agent community.

Zeus: A toolkit for building distributed multiagent systems

The multiagent systems approach of knowledge- level cooperation between autonomous agents promises significant benefits to distributed systems engineering, such as enhanced interoperability, scalability, and reconfigurability. However, thus far, because of the innate difficulty of constructing multiagent systems, this promise has been largely unrealized. Hence there is an emerging desire among agent developers to move away from developing point solutions to point problems in favor of developing methodologies and toolkits for building distributed multiagent systems. This philosophy led to the development of the ZEUS Agent Building Toolkit, which facilitates the rapid development of collaborative agent applications through the provision of a library of agent- level components and an environment to support the agent-building process. The ZEUS toolkit is a synthesis of established agent technologies with some novel solutions to provide an integrated collaborative agent-building environment.

A perspective on software agents research

This paper sets out, ambitiously, to present a brief reappraisal of software agents research. Evidently, software agent technology has promised much. However, some five years after the word ‘agent’ came into vogue in the popular computing press, it is perhaps time the efforts in this fledgling area are thoroughly evaluated with a view to refocusing future efforts. We do not pretend to have done this in this paper—but we hope we have sown the first seeds towards a thorough first five-year report on the software agents area. The paper contains some strong views not necessarily widely accepted by the agent community.

Intelligent tutoring systems: an overview

This is a non-expert overview of Intelligent Tutoring Systems (ITSs), a way in which Artificial Intelligence (AI) techniques are being applied to education. It introduces ITSs and the motivation for them. It looks at its history: its evolution from Computer-Assisted Instruction (CAI). After looking at the structure of a ‘typical’ ITS, the paper further examines and discusses some other architectures. Several classic ITSs are reviewed, mainly due to their historical significance or because they best demonstrate some of the principles of intelligent tutoring. A reasonably representative list of ITSs is also provided in order to provide a better appreciation of this vibrant field as well as reveal the scope of existing tutors. The paper concludes, perhaps more appropriately, with some of the authors viewpoints on a couple of controversial issues in the intelligent tutoring domain.

An Introduction to Agent Technology

Intelligent agent technology is a rapidly developing area of research. However, in reality, there is a truly heterogeneous body of work being carried out under the ‘agent’ banner. In this paper, software agent technology is introduced by briefly overviewing the various agent types currently under investigation by researchers.

The Stability, Scalability and Performance of Multi-agent Systems

Much has been published on the functional properties of multi-agent systems (MASs) including their co-ordination rationality and knowledge modelling. However, an important research area which has so far received only scant attention covers the non-functional properties of MASs which include performance, scalability and stability issues — clearly thes become increasingly important as the MAS field matures, and as more practical MASs become operational. An understanding of how to evaluate and assess such non-functional properties, and hence how to improve on them by altering the underlying MAS design, is gradually emerging as a pressing concern. This paper presents preliminary work to address such concerns; particularly, it investigates the performance and scalability of a multi-agent model we have developed.Firstly, this paper defines performance, scalability and stability within the context of multi-agent applications. Following, we describe a multi-agent model that we later use to illustrate our first attempts at evolving a procedure for analysing such non-functional properties of MASs. Next, we report on our initial attempts to investigate the performance and scalability of the multi-agent model. Finally, the significance of these results in particular and of such investigations in general is discussed.

ZEUS: a toolkit and approach for building distributed multi-agent systems

The innate difficulty of constructing multi-agent systems has motivated agent developers to move away from developing point solutions to point problems in favour of developing methodologies and toolkits for building distributed multi-agent systems. This philosophy led to the development of the ZEUS Agent Building Toolkit, which facilitates the rapid development of collaborative agent applications through the provision of a library of agent-level components and an environment to support the agent building process. The ZEUS toolkit is a synthesis of established agent technologies with some novel solutions to provide an integrated collaborative agent building environment.

The ZEUS Agent Building Tool-kit

There is an emerging desire among agent researchers to move away from developing point solutions to point problems in favour of developing methodologies and tool-kits for building distributed multi-agent systems. This philosophy has led to the development of the ZEUS agent building tool-kit, which facilitates the engineering of collaborative agent applications through the provision of a library of agent-level components and an environment to support the agent building process. The ZEUS tool-kit is a synthesis of established agent technologies with some novel solutions that provide an integrated environment for rapid software engineering of collaborative agent applications.

Agent-mediated electronic commerce: issues, challenges and some viewpoints

Electronic commerce is set to be a major application area ol’ ngcnt technology, yet it is not very clear from our published agents literature what the core research issues that we need to address in this area are. In this paper, we examine this important domain of agent-mediated chxtronic commerce highlighting in particular some its key issues and challenges. It strongly takes the view that a research arca is defined by its problems, not its methods, and hence we try and tease out some of the problemslsubproblems that define agent-mediated electronic commerce, We present them as a Iist of open questions. Next, the authors propound their viewpoints on these questions in the hope that it stimulates and influences the research that need to be carried out in order to realise truly useable, agent-mediated or agent-enhanced clcctronic commerce, This paper is a part summary of the views propounded by some of the panellists at a panel session on agent-mediated electronic commerce at the 2”d International Conference on Autonomous Agents held in Minneapolis, May 1998.

Visualising and debugging distributed multi-agent systems

Visualising the behaviour of systems with distributed data, control and process is a notoriously difficult task. Each component in the distributed system has only a local view of the whole set-up, and the onus is on the user to integrate, into a coherent whole, the large amounts of limited information they provide. In this paper, we describe an architecture and an implemented system for visualising and controlling distributed multi-agent applications. The system comprises a suite of tools, with each tool providing a different perspective of the application being visualised. Each tool interrogates the components of the distributed application, collates the returned information and presents this information to users in an appropriate manner. This in essence shifts the burden of inference from the user to the visualiser. Our visualiser has been evaluated on four distributed multi-agent systems: a travel management application, a telecommunications network management application, a business process management demonstrator, and an electronic commerce application. Lastly, we briefly show how the suite of tools can be used together for debugging multi-agent applications an approach we refer to as debugging via corroboration.