Andrea Omicini

Environment as a first class abstraction in multiagent systems

The current practice in multiagent systems typically associates the environment with resources that are external to agents and their communication infrastructure. Advanced uses of the environment include infrastructures for indirect coordination, such as digital pheromones, or support for governed interaction in electronic institutions. Yet, in general, the notion of environment is not well defined. Functionalities of the environment are often dealt with implicitly or in an ad hoc manner. This is not only poor engineering practice, it also hinders engineers to exploit the full potential of the environment in multiagent systems. In this paper, we put forward the environment as an explicit part of multiagent systems.We give a definition stating that the environment in a multiagent system is a first-class abstraction with dual roles: (1) the environment provides the surrounding conditions for agents to exist, which implies that the environment is an essential part of every multiagent system, and (2) the environment provides an exploitable design abstraction for building multiagent system applications. We discuss the responsibilities of such an environment in multiagent systems and we present a reference model for the environment that can serve as a basis for environment engineering. To illustrate the power of the environment as a design abstraction, we show how the environment is successfully exploited in a real world application. Considering the environment as a first-class abstraction in multiagent systems opens up new horizons for research and development in multiagent systems.

Coordination for Internet Application Development

The adoption of a powerful and expressive coordination model represents a key-point for the effective design and development of Internet applications. In this paper, we present the TuCSoN coordination model for Internet applications based on network-aware and mobile agents, and show how the adoption of TuCSoN can positively benefit the design and development of such applications, firstly in general terms, then via a TuCSoN-coordinated sample application. This is achieved by providing for an Internet interaction space made up of a multiplicity of independently programmable communication abstractions, called tuple centres, whose behaviour can be defined so as to embody the laws of coordination.

SODA: Societies and Infrastructures in the Analysis and Design of Agent-Based Systems

The notion of society should play a central role in agent-oriented software engineering as a first-class abstraction around which complex systems can be designed and built as multi-agent systems. We argue that an effective agentoriented methodology should account for inter-agent aspects by providing engineers with specific abstractions and tools for the analysis and design of agent societies and agent environments. In this paper, we outline the SODA agent-oriented methodology for the analysis and design of Internet-based systems. Based on the core notion of task, SODA promotes the separation of individual and social issues, and focuses on the social aspects of agent-oriented software engineering. In particular, SODA allow the agent environment to be explicitly modelled and mapped onto suitably-defined agent infrastructures.

Artifacts in the A&A meta-model for multi-agent systems

In this article we focus on the notion of artifact for agents in multi-agent systems (MAS) as a basis for a new meta-model promoting the modelling and engineering of agent societies and MAS environment as first-class entities. Its conceptual foundations lay upon theories and results coming from computational sciences as well as from organisational and cognitive sciences, psychology, computer supported cooperative work (CSCW), anthropology and ethology. In the resulting agents & artifacts (A&A) meta-model, agents are the (pro-)active entities in charge of the goals/tasks that altogether build up the whole MAS behaviour, whereas artifacts are the reactive entities providing the services and functions that make individual agents work together in a MAS, and that shape agent environment according to the MAS needs. After presenting the scientific background, we define the notions of artifact in the A&A meta-model, discuss how it affects the notion of intelligence in MAS, and show its application to a number of agent-related research fields.

Challenges and Research Directions in Agent-Oriented Software Engineering

Agent-based computing is a promising approach for developing applications in complex domains. However, despite the great deal of research in the area, a number of challenges still need to be faced (i) to make agent-based computing a widely accepted paradigm in software engineering practice, and (ii) to turn agent-oriented software abstractions into practical tools for facing the complexity of modern application areas. In this paper, after a short introduction to the key concepts of agent-based computing (as they pertain to software engineering), we characterise the emerging key issues in multiagent systems (MASs) engineering. In particular, we show that such issues can be analysed in terms of three different “scales of observation”, i.e., in analogy with the scales of observation of physical phenomena, in terms of micro, macro, and meso scales. Based on this characterisation, we discuss, for each scale of observation, what are the peculiar engineering issues arising, the key research challenges to be solved, and the most promising research directions to be explored in the future.

From tuple spaces to tuple centres

Abstract A tuple centre is a tuple space whose behaviour can be defined by means of reactions to communication events. In this paper, we motivate and define the notion of tuple centre, both conceptually and formally. Then, we show how adopting a tuple centre for the coordination of a multiagent system can benefit both the system design and the overall system performance.

Agent-Oriented Software Engineering for Internet Applications

The metaphors of autonomous agents and agent societies have the potential to make a signifiant impact in the processes of analysis, design and development of complex software systems on the Internet. In this chapter, we concentrate predominantly on agent societies, and show how work on coordination models and technologies provides a powerful framework for the engineering of Internet-based, multi-agent systems. First, we introduce the concepts of agent, multi-agent system, and agent-oriented software engineering, and highlight the specific issues that arise when we take the Internet as the environment that agents inhibit. We then provide a brief survey of the state of the art in the area of agent-oriented methodologies, paying particular attention to the Gaia methodology for agent-oriented analysis and design. Gaia was originally concieved for benevolent agents inhabiting closed systems. However, to broaden its scope, we show how insights from the area of coordination models can be incorporated in order to make it more suitable for developing Internet-based applications.

CArtAgO: a framework for prototyping artifact-based environments in MAS

This paper describes CArtAgO, a framework for developing artifact-based working environments for multiagent systems (MAS). The framework is based on the notion of artifact, as a basic abstraction to model and engineer objects, resources and tools designed to be used and manipulated by agents at run-time to support their working activities, in particular the cooperative ones. CArtAgO enables MAS engineers to design and develop suitable artifacts, and to extend existing agent platforms with the possibility to create artifact-based working environments, programming agents to exploit them. In this paper, first the abstract model and architecture of CArtAgO is described, then a first Java-based prototype technology is discussed.

Software Engineering for Large-Scale Multi-Agent Systems

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Coordination of Internet Agents

Flexible and efficient naming, migration and coordinat ion schemes are critical components of concurrent and distributed systems. This chapter describ es actor naming and coordina t ion models and infrastructures, which enable th e development of mobile agent syst ems. A travel agent example is used to motivate th e requirements and proposed solut ions for naming, migration and coordination. Universal Actor Names provide location and migration t ransparency, while ActorSpaces enable t he unanticipated connection of users , agent s and servi ces in t he open, dynamic nature of todays networks. An actor-based architecture, th e World Wide Computer , is presented as a basis for implementing higher-level naming and coordin ation models for Internet-based agent syst ems. Finally, multiagent coordination is accomplished with cyborgs, an abs traction which provides a unit for group migration and resour ce consumpt ion through th e use of e-cash.