Our goal in this paper is to introduce and motivate a methodology, called Tropos, for building agent oriented software systems. Tropos is based on two key ideas. First, the notion of agent and all related mentalistic notions (for instance goals and plans) are used in all phases of software development, from early analysis down to the actual implementation. Second, Tropos covers also the very early phases of requirements analysis, thus allowing for a deeper understanding of the environment where the software must operate, and of the kind of interactions that should occur between software and human agents. The methodology is illustrated with the help of a case study. The Tropos language for conceptual modeling is formalized in a metamodel described with a set of UML class diagrams.

In this article we discuss the potential uses of mobile agents in network management and define software agents and a navigation model that determines agent mobility. We list a number of potential advantages and disadvantages of mobile agents and include a short commentary on the ongoing standardization activity. The core of this article comprises descriptions of several actual and potential applications of mobile agents in the five OSI functional areas of network management. A brief review of other research activity in the area and prospects for the future conclude the presentation. SURVEYS IEEE# COMMUNICATIONS www.comsoc.org/pubs/surveys IEEE Communications Surveys . http://www.comsoc.org/pubs/surveys . Fourth Quarter 1998 . Vol. 1 No. 1 IEEE Communications Surveys . http://www.comsoc.org/pubs/surveys . Fourth Quarter 1998 . Vol. 1 No. 1 3 [13]. Examples of the former approach include AgentTCL [14, 15] and Telescript [16], and the latter, Aglets [17]. To make use of mo...

We address the issues of semantics and conversations for agent communication languages and the Knowledge Query Manipulation Language (KQML) in particular. Based on ideas from speech act theory, we present a semantic description for KQML that associates "cognitive" states of the agent with the use of the language's primitives (performatives). Wehave used this approach to describe the semantics for the whole set of reserved KQML performatives. Building on

Computing and telecommunications are maturing, and the next century promises a shift away from technology-driven general-purpose devices. Instead, we will focus on the needs of consumers: easy-to-use, low-maintenance, portable, ubiquitous, and ultra-reliable task-specific devices. Such devices, although not as limited by computational speed or communication bandwidth, will instead be constrained by new limits on size, form-factor, and power consumption. Data that they generate will need to be injected into the Internet and find its way to the services to which the user has subscribed. This is not simply a problem of ad-hoc networking, but one that requires re-thinking our basic assumptions regarding network transactions and challenges us to develop entirely new models for distributed services. Network topologies will be intermittent and services will have to be discovered independently of user guidance. In fact, data transfers from user interfaces to services and back, will need to become invisible to the user and guided by the task rather than explicit commands. This paper outlines a vision of this future and identifies research problems that will require our attention in the areas of user interfaces, distributed services, and networking infrastructure. 1

Abstract. Tropos is a novel agent-oriented software development methodology founded on two key features: (i) the notions of agent, goal, plan and various other knowledge level concepts are fundamental primitives used uniformly throughout the software development process; and (ii) a crucial role is assigned to requirements analysis and specification when the system-to-be is analyzed with respect to its intended environment. This paper provides a (first) detailed account of the Tropos methodology. In particular, we describe the basic concepts on which Tropos is founded and the types of models one builds out of them. We also specify the analysis process through which design flows from external to system actors through a goal analysis and delegation. In addition, we provide an abstract syntax for Tropos diagrams and other linguistic constructs. 1

Tools for filtering the World Wide Web exist, but they are hampered by the difficulty of capturing user preferences in such a dynamic environment. We explore the acquisition of user profiles by unobtrusive monitoring of browsing behaviour and application of supervised machine-learning techniques coupled with an ontological representation to extract user preferences. A multi-class approach to paper classification is used, allowing the paper topic taxonomy to be utilised during profile construction. The Quickstep recommender system is presented and two empirical studies evaluate it in a real work setting, measuring the effectiveness of using a hierarchical topic ontology compared with an extendable flat list.

This paper focuses on intrusion detection and countermeasures with respect to widely-used operating systems and networks. The design and architecture of an intrusion detection system built from distributed agents is proposed to implement an intelligent system on which data mining can be performed to provide global, temporal views of an entire networked system. A starting point for agent intelligence in our system is the research into the use of machine learning over system call traces from the privileged sendmail program on UNIX. We use a rule learning algorithm to classify the system call traces for intrusion detection purposes and show the results.

There is an emerging consensus on the need to develop methodologies and tool-kits for building distributed multi-agent systems. This paper presents ZEUS, an advanced development tool-kit for constructing collaborative agent applications. ZEUS is a culmination of a careful synthesis of established agent technologies with the addition of some new ones, to provide an integrated environment for the rapid software engineering of collaborative agent applications. ZEUS defines a multi-agent system design methodology, supports the methodology with an environment for capturing user specification of agents, and automatically generates the executable source code of the user-defined agents. We also report on preliminary informal evaluation of ZEUS on three domains. Keywords Agent architectures, distributed multi-agent systems, constructing collaborative agent applications. I. Introduction This paper describes ZEUS, an advanced tool-kit for building distributed multi-agent applications. The too...

We explore a novel ontological approach to user profiling within recommender systems, working on the problem of recommending on-line academic research papers. Our two experimental systems, Quickstep and Foxtrot, create user profiles from unobtrusively monitored behaviour and relevance feedback, representing the profiles in terms of a research paper topic ontology. A novel profile visualization approach is taken to acquire profile feedback. Research papers are classified using ontological classes and collaborative recommendation algorithms used to recommend papers seen by similar people on their current topics of interest. Two small-scale experiments, with 24 subjects over 3 months, and a large-scale experiment, with 260 subjects over an academic year, are conducted to evaluate different aspects of our approach. Ontological inference is shown to improve user profiling, external ontological knowledge used to successfully bootstrap a recommender system and profile visualization employed to improve profiling accuracy. The overall performance of our ontological recommender systems are also presented and favourably compared to other systems in the literature.

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 5-year report of the software agents area. The paper contains some strong views not necessarily widely accepted by the agent community.