Abstracts

Thesis

Eine modulare Architektur für dienstbasierte Interaktionen zwischen Agenten

(a modular architecture for service-based interactions among agents)

Ralf Sesseler (2002)

Computer networks like the Internet provide a new infrastructure bearing new possibilities for the realisation of service platforms, but also raising new requirements. Suppliers, brokers, and consumers of goods and services profit from the flexibility and dynamics as well as from the independency from time and location. To benefit from this potential, the open, distributed, and heterogeneous character of the networks needs to be utilised by new technologies.
A promising approach are software agents, which can act and interact as autonomous specialists in the networks. CASA is an architecture for multi-agent systems that offers a modular structure and agents with a high degree of flexibility and interoperability. By this, it provides a suitable basis for the realisation of service platforms in computer networks. CASA is divided into three design levels for agent composition, agent control, and agent societies, which are completed by the formal language CAL for agent specification.
Individual agents are assembled depending upon their tasks from reusable components. Even at run-time, components can be reconfigured as well as added, removed, or exchanged without affecting the current work of the agent. Thus, agents are easily created and adapted to changing tasks.
Agent control is based upon a knowledge-based control scheme that integrates reactive, deliberative, and interactive behaviour. Formal knowledge structures provide an abstract layer for the specification and analysis of agents and build the ground for a flexible, autonomous behaviour control.
In addition, formal knowledge is utilised as the content of communications and to describe the interactive capabilities of agents, thereby enabling the interoperability needed by agent societies. Interactions are represented as service acts that agents provide and use in order to delegate tasks. Together with an agent infrastructure that administers agents and services, the service scheme allows flexible and dynamic collaborations among agents and the integration of interactions into behaviour control.
The agent description language CAL is a combination of formal logics and programming language. It covers all aspects of representing, using, and communicating knowledge by agents.
CASA is an open and scalable architecture to build flexible, dynamic multi-agent systems that supports modularity and interoperability at all architectural layers.

Das Agentenmodell InteRRaP im Vergleich mit kognitiven Architekturen

(the agent model InteRRaP in comparison with cognitive architectures)

Ralf Sesseler (1996)

Kognitive Architekturen integrieren verschiedene kognitive Fähigkeiten - wie beispielsweise Planen, Wissensrepräsentation und Lernen - zu einem Gesamtsystem, sowohl um einen möglichst großen Bereich an intelligenten Fähigkeiten abzudecken, als auch um eine gegenseitige Unterstützung der einzelnen Komponenten untereinander mit einer sich daraus ergebenden höheren Funktionalität zu erreichen. Die Motivation für die Gestaltung kognitiver Architekturen besteht in einem besseren Verständnis von Intelligenz im allgemeinen, in der Modellierung der menschlichen Kognition sowie in der Entwicklung intelligenter technischer Anwendungen. Das Ziel dieser Diplomarbeit ist eine Untersuchung der Stärken und Schwächen des am DFKI entwickelten Agentenmodells INTERRAP im Vergleich zu anderen kognitiven Architekturen. Dieser Vergleich besteht aus einer strukturellen Gegenüberstellung, bei der die einzelnen Komponenten der verschiedenen Architekturen sowie deren Integration in der Gesamtarchitektur betrachtet werden, und aus einer funktionalen Analyse, bei der untersucht wird, wie die Integration der einzelnen Komponenten die Funktionalität der Gesamtarchitektur unterstützt. Als Vergleichsarchitekturen zu INTERRAP werden ACT, TOK/PRODIGY und SOAR betrachtet.

Conferences

Software Agent Technology in Mobile Service Environments

Ralf Sesseler, Alexander Keiblinger, Nicolas Varone (2002)

The demand for mobility in modern societies leads to the development of smaller and wireless networked computational devices. The resulting service environments for future mobile service networks will be complex. The individual character of future services requires highly flexible service infrastructures and development frameworks. We propose agent technology for the implementation of mobile services to reduce the complexity of mobile service infrastructures. We present JIAC IV, a Java-based agent framework designed with the service as a modelling abstraction. JIAC IV delivers a highly integrated set of tools for the analysis, design, and development of agent-based software services. Utilising the JIAC IV agent toolkit, a service developer focuses on application logic using agent services and the co-operation between agents. This will lead to faster service development cycles despite the increasing complexity of the environments. Encapsulation and communication between independent functional units can be a way to manage future complexity of service networks, and software agents are its technological implementation.

JIAC IV An Open, Scalable Agent Architecture for Telecommunications Applications

Ralf Sesseler, Sahin Albayrak (2002)

JIAC IV is a generic agent toolkit with an emphasis on the realisation of applications in the areas of telecommunications and electronic commerce. We motivate the need for open, scalable, and flexible systems and hence the advantages of agent technology in these areas. Then, we describe the basic architectural principles of CASA, which builds the structural and functional base of agents in JIAC IV. The component framework of CASA makes agents highly scalable and allows reconfiguration at run-time. The control architecture of CASA combines reactive, deliberative, and interactive capabilities to control agent behaviour in a flexible manner.

Service-ware Framework for Developing 3G Mobile Services

Ralf Sesseler, Sahin Albayrak (2001)

JIAC IV is a generic agent toolkit which is intended as a service-ware framework for the realisation of applications in the areas of telecommunications, mobile services, and electronic commerce. We motivate the need for open, scalable, and flexible systems and hence the advantages of agent technology in these areas. Then, we describe the basic architectural principles of CASA, which builds the structural and functional base of agents in JIAC IV. The component framework of CASA makes agents highly scalable and allows reconfiguration at run-time. The control architecture of CASA combines reactive, deliberative, and interactive capabilities to control agent behaviour in a flexible manner.

Agent-based Marketplaces for Electronic Commerce

Ralf Sesseler, Sahin Albayrak (2001)

Keywords: multi-agent systems, electronic commerce, electronic marketplaces

We transfer the common notion of marketplaces as locations for trading to infrastructures for electronic commerce. Then, we argue that multi-agent systems are a promising technology to realise such electronic marketplaces because of the autonomous, task-oriented, and interactive capabilities of agents in dynamic and distributed environments. We present the agent toolkit JIAC IV and describe its special features that make it a suitable candidate for the realisation of electronic marketplaces. In more detail, we describe how interactions between agents are made more flexible and reliable by a service scheme, which covers generic aspects of interactions.

Building Agents for Service Provisioning out of Components

Ralf Sesseler (2001)

Keywords: agent architectures, agent-based service provisioning, multi-agent collaboration, communication protocols

CASA is an open, scalable agent architecture for service provisioning. Its interaction scheme between agents is based on a formalized concept of services to allow dynamic and flexible selection and combination of services and their providers.

Journals

Agent-based Telematic Services and Telecommunication Applications

Stefan Fricke, Karsten Bsufka, Jan Keiser, Torge Schmidt, Ralf Sesseler, Sahin Albayrak (2001)

The future telecommunications world will induce significant changes to the involved actors as well as to the quality and quantity of offered services. This article points out the determining factors, trends, and demands for infrastructure functionality of future service architecures and then motivates why an agent-based approach is adequate as underlying technology. We present the toolkit JIAC as a potential candidate for realizing such future services and applications as agent-based systems. It provides a scalable agent architecture, which integrates telecommunication-specific management functionality, cooperative service usage, and strong security mechanisms. A runtime environment adds further service infrastructure, authentication, and authorization. The toolkit is completed by a set of tools for rapid development and deployment of services as well as for managing purposes.