Enrico Denti

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.

Multi-paradigm Java-Prolog integration in tuProlog

tuProlog is a Java-based Prolog engine explicitly designed to be minimal, dynamically configurable, and support full and clean Prolog/Java integration. In this paper, we discuss the tuProlog approach to Prolog/Java multi-paradigm integration. After tuProlog motivations and requirements, we present some examples of bidirectional Prolog/Java integration and discuss the model and architecture of the tuProlog system. Then, we focus on the specific issue of the access to Java resources from tuProlog, discuss the essentials of its implementation, and compare it extensively with many other relevant related approaches and systems.

Programmable Coordination Media

The design, development and maintenance of multi-component software systems often suffer from the lack of suitable coordination abstractions. The aim of this paper is to show the benefits of coordination models based on global communication abstractions whose behaviour is not fixed, but is extensible so as to accomplish the intended behaviour of the whole system. Accordingly, we propose the notion of programmable coordination medium as an abstraction provided by the coordination model around which the global behaviour of a coordination architecture can be designed. As an example, we show how a Linda-based approach can be empowered by exploiting the notion of programmable tuple space, as supported by the ACLT coordination model.

tu Prolog: A Light-Weight Prolog for Internet Applications and Infrastructures

Intelligence and interaction are two key-issues in the engineering of todaycomp lex systems, like Internet-based ones. To make logic languages accomplish their vocation of sound enabling technologies for intelligent components, we first need their implementations to strictly meet some engineering properties such as deployability, configurability, and scalability. Then, we should provide them with a wide range of interaction capabilities, according to standards and common practices. This would make logic-based systems also viable tools to build deployable, configurable, dynamic, and possibly intelligent infrastructures. In this paper, we present tuProlog, a light-weight Java-based system allowing configurable and scalable Prolog components to be built and integrated into standard Internet applications according to a multiplicityof different interaction patterns, like JavaBeans, RMI, CORBA, and TCP/IP. Even more, tuProlog offers basic coordination capabilities in terms of logic tuple spaces, which allow complex Internet-based architectures to be designed and governed. This makes it possible to use tuProlog as the core enabling technologyf or Internet infrastructures - as in the case of the TuCSoN and LuCe infrastructures for the coordination of Internet-based multi-agent systems.

Tuple-based technologies for coordination

By tuple-based technologies we refer to any coordination system that uses associative access to shared dataspaces for communication / synchronization purposes.

VIRTUAL ENTERPRISES AND WORKFLOW MANAGEMENT AS AGENT COORDINATION ISSUES

Agents and multiagent systems (MAS) have already proved suitable for dealing with the complexity of today B2B application scenarios. Application environments such as virtual enterprises (VE) and inter-organizational workflow management systems (WfMS) specially call for the integration of heterogeneous resources, services, and processes. In this article, we first recognize VE and workflow management as agent coordination problems, then discuss how objective coordination — that is, coordination from outside agents — can help to model VE and WfMS. Finally, we show the impact of an agent coordination infrastructure like

SODA: a roadmap to artefacts

\mathsf{TuCSoN}

Zooming multi-agent systems

on the engineering of highly dynamic VE and WfMS, by discussing a simple case study.

Activity theory as a framework for MAS coordination

An artefact for MASs is an entity not driven by an inner goal (as agents are), but used by agents to achieve their own goals. In this paper, we assume agents and artefacts as first-class entities in MAS engineering, and claim that agent-oriented methodologies should exploit these two abstractions as the basic bricks for the whole engineering process. As a first testbed, we take the SODA agent-oriented methodology and draw a possible roadmap for its extension toward the notion of artefact.

Coordination Tools for MAS Development and Deployment

Complex systems call for a hierarchical description. Analogously, the engineering of non-trivial MASs (multiagent systems) requires principles and mechanisms for a multi-layered description, which could be used by MAS designers to provide different levels of abstraction over MASs. In this paper, we first advocate the need for zooming mechanisms, promoting a coherent and consistent multi-layered view of agent systems. After surveying the best-known AOSE methodologies, we focus on the scaling mechanisms of the OPM process-oriented methodology. Then, by adopting SODA as our reference, we show how an AOSE methodology can be enhanced with simple yet expressive zooming mechanisms. Finally, we present a simple case study where the enhanced agent-oriented methodology (SODA +zoom) is exploited and put to the test.