Bas Testerink

A framework for programming norm-aware multi-agent systems

We propose a programming framework for the implementation of norm-aware multi-agent systems. The framework integrates the N-2APL norm-aware agent programming language with the 2OPL organisation programming language. Integration of N-2APL and 2OPL is achieved using a tuple space which represents both the (brute) state of the multi-agent environment and the detached norms and sanctions comprising its normative state. To the best of our knowledge, this is the first implementation of an integrated framework for norm-aware MAS in which autonomous agents deliberate about whether to conform to the norms imposed by a normative organisation. The use of a tuple space makes it straightforward to integrate other system components. To illustrate the flexibility of our framework, we briefly describe its application in a novel normative application, a mixed reality game called GeoSense. We show how GeoSense game rules can be expressed as conditional norms with deadlines and sanctions, and how agents can deliberate about their individual goals and the norms imposed by the game.

Norms in distributed organizations

Due to external requirements we cannot always construct a centralized organization, but have to construct one that is distributed. A distributed organization is a network of organizations which can locally observe and control the environment. In this paper we analyze how norms can be enforced through the joint effort of the individual local organizations. Norm violations are detected by monitoring. Sanctioning compensates the violations of norms. The main problem is to map the required data for monitoring, and the required control capabilities for sanctioning, to the local observe/control capabilities of organizations. Our investigation focuses on exploring the solution space of this problem, the properties of proper solutions and practical considerations when developing a solution.

Distributed Controllers for Norm Enforcement

This paper focuses on computational mechanisms that control the behavior of autonomous systems at runtime without necessarily restricting their autonomy. We build on existing approaches from runtime verification, control automata, and norm-based systems, and define norm-based controllers that enforce norms by modifying system behavior at runtime to make it norm compliant. For many applications, an autonomous system should comply with a set of norms. We extend our approach to a distributed setting, where a set of norm-based controllers jointly modify the runtime behavior of an autonomous system. The norms that a set of norm-based controllers jointly enforce are investigated and characterized in terms of the norms that are enforced by individual norm-based controllers. We show that a set of norm-based controllers is able to modify the runtime behavior of an autonomous system to make it compliant with all norms that the individual norm-based controllers aim at enforcing.

Security and robustness for collaborative monitors

Decentralized monitors can be subject to robustness and security risks. Robustness risks include attacks on the monitors infrastructure in order to disable parts of its functionality. Security risks include attacks that try to extract information from the monitor and thereby possibly leak sensitive information. Formal methods to analyze the design of a monitor with respect to these issues can help to create more secure designs and/or identify critical parts. In this paper we specify a model for analyzing robustness and security risks for collaborative monitors constructed from a network of local monitors.

A SUMO Extension for Norm-Based Traffic Control Systems

Autonomous vehicles will most likely participate in traffic in the near future. The advent of autonomous vehicles allows us to explore innovative ideas for traffic control such as norm-based traffic control. A norm is a violable rule that describes correct behavior. Norm-based traffic controllers monitor traffic and effectuate sanctions in case vehicles violate norms. In this paper, we present an extension of SUMO that enables the user to apply norm-based traffic controllers to traffic simulations. In our extension, named TrafficMAS, vehicles are capable of making an autonomous decision on whether to comply with norms. We provide a description of the extension, a summary on its implementation and demonstrative experiments.

Specifications for Peer-to-Peer Argumentation Dialogues

In this paper, we propose a generic specification framework for argumentation dialogue protocols in an open multi-agent system. The specification framework is based on reusable elements – dialogue templates – which are realized as an open-source implementation. We provide operational semantics and show formally how templates can be used to determine the possible dialogues. Furthermore, for open multi-agent systems we need to be able to specify peer-to-peer dialogues, where the agents themselves are in a position to know whether their dialogue actions are legal according to the protocol without relying on central entities, institutes or middleware. We prove that all protocols that can be specified in our framework are peer-to-peer suitable.

Design patterns for multi-agent programming

Various agent-based programming languages and frameworks have been proposed to support the development of autonomous agents and multi-agent systems. They have provided a valuable contribution to the identification and operationalisation of agent concepts and abstractions by proposing specific programming constructs. Unfortunately, these contributions have not yet been widely adopted by industry. In this paper, we follow the argument that multi-agent programming technology can find its way to industry by providing a methodology that guides the development of autonomous agents and multi-agent systems in standard programming technology. The proposed methodology explains how some characteristic concepts and abstractions related to autonomous agents and multi-agent systems can be implemented in object-oriented technology. This is done by initiating a Java library of object-oriented design patterns for some characteristic but established programming constructs that have been developed in some agent-based programming languages.

Organizational Replication Using Inheritance

Electronic organizations are not operating in an isolated manner. Instead, they form an ecosystem defined by various relationships. We will look at organizations that can share norms and/or a hierarchical bond. Determining what is the set of norms that should be shared and acknowledged among organizations that implement identical concepts, as well as how responsibility is delegated between an organization and sub-organizations, represent issues that require a thorough investigation. This paper presents a taxonomy for the possible relationships that may bind two organizations and defines how the normative specifications are inherited from the abstract concepts of organizations to the actual entities instantiating these concepts.

From Multi-Agent Programming to Object Oriented Design Patterns

Various agent-based programming languages and frameworks have been proposed to support the development of multi-agent systems. They have contributed to the identification and operationalisation of multi-agent system concepts, features and abstractions by proposing spe- cific programming constructs. Unfortunately, these contributions have not yet been widely adopted by industry. In this paper, we follow the argument that multi-agent programming technology can find its way to industry by introducing design patterns for the existing agent constructs in standard software technology. We provide some object-oriented design patterns based on the programming constructs that have been developed in agent-based programming languages.