MaNEA: A distributed architecture for enforcing norms in open MAS

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Abstract

Norms have been promoted as a coordination mechanism for controlling agent behaviours in open MAS. Thus, agent platforms must provide normative support, allowing both norm-aware and non-norm-aware agents to take part in MAS that are controlled by norms. In this paper, the most relevant proposals on the definition of norm enforcement mechanisms are analyzed. These proposals present several drawbacks that make them unsuitable for open MAS. In response to these problems, this paper describes a new Norm-Enforcing Architecture aimed at controlling norms in open MAS. Specifically, this architecture supports the creation and deletion of norms on-line as well as the dynamic activation and expiration of instances. Finally, it can dynamically adapt to different scale MAS. The efficiency of this architecture has been experimentally evaluated and the results are shown in this paper.

Introduction

The main applications of Multi-Agent Systems (MAS) support large scale open distributed systems. These systems are characterized by the heterogeneity of their participants; their limited trust; a high uncertainty; and the existence of individual goals that might be in conflict (Artikis and Pitt, 2001). In these scenarios, norms are conceived as an effective mechanism for achieving coordination and ensuring social order; i.e., norms represent an effective tool for regulating the actions of software agents and the interactions among them (López et al., 2006). Most of the proposals on methodologies and guidelines aimed at developing open MAS (Argente et al., 2011b, Dignum et al., 2005) are based on organizational concepts, such as norms. These concepts facilitate the analysis and design of coordination and collaboration mechanisms for MAS. Therefore, norms should be considered in the design and specification of the MAS (Criado et al., 2011b). As pointed out in Castelfranchi (2003), the use of norms in MAS allows better results to be achieved in dynamic and complex environments. Specifically, the fact that agents can violate norms autonomously allows a better adaptation to the environmental changes. Finally, the occurrence of norm violations can evidence the need to adapt the MAS (Bernon et al., 2003). Agent platforms are the software that supports the development and execution of MAS. Thus, norms must be also considered in the design and implementation of agent platforms (Criado et al., 2011b). As a consequence, agent platforms must implement norms in an optimized way, given that in open MAS the internal states of agents are not accessible (Criado et al., 2011a). Therefore, norms cannot be imposed as agent's beliefs or goals, but they must be implemented in the platforms by means of control mechanisms (Grossi et al., 2007).

This paper shows an overview of the most relevant works on norm implementation. This paper considers the main challenges of open MAS and points out the main deficiencies and drawbacks of agent platforms and infrastructures when supporting norms. With the aim of overcoming some of these problems, in this paper a Norm-Enforcing Architecture, known as MaNEA, is proposed. Specifically, MaNEA has been integrated into the Magentix2 platform.1 The Magentix2 platform allows the management of open MAS in a secure and optimized way. Its main objective is to bring agent technology to real domains: business, industry, e-commerce, among others. This goal entails the development of more robust and efficient mechanisms for enforcing norms that control these complex applications.

This paper is organized as follows: Section 2 contains the analysis of the main proposals on norm enforcement; Section 3 describes briefly the Magentix2 platform; Section 4 describes the main components of MaNEA; Section 5 illustrates the performance of MaNEA through a case study; Section 6 contains an evaluation of this architecture; and, finally, Section 7 contains conclusions and future works.

Section snippets

Related work

Most of the proposals on norms for controlling MAS tackle this issue from a theoretical perspective (Boella, 2004, Sergot, 1998). However, there are also works on norms from a computational point of view. These works propose control mechanisms for norms to have an effective influence on agent behaviours (Grossi et al., 2007). These control mechanisms are classified into two categories (Grossi et al., 2007): regimentation mechanisms, which consist of making the violation of norms impossible; and

The Magentix2 platform

Magentix2 is an agent platform for open MAS in which heterogeneous agents interact and organize themselves into Virtual Organizations (VOs) (Foster et al., 2001). VOs are open systems formed by the grouping and collaboration among heterogeneous entities. In VOs there is a separation between form and function that requires defining how behaviour will take place (Ferber et al., 2005). VOs are social entities formed by agents that try to achieve the organizational goals. These agents are organized

Norm-enforcing architecture: MaNEA

The main purpose of MaNEA (Magentix2 Norm-Enforcing Architecture) is to endow the Magentix2 platform with an infrastructure capable of controlling norms in open MAS where unforeseen scenarios may occur. Therefore, the number of agents and the situations that must be controlled through norms may change at runtime. For this reason, MaNEA has been designed as a distributed architecture. Specifically, MaNEA has been distributed over two layers (see Fig. 6):

  • The highest layer of MaNEA is formed by

Case study

The first step that any engineer must perform to implement a MAS in Magentix2 is to model the MAS based on the VO approach. To facilitate this task, engineers are encouraged to use the GORMAS guidelines (Argente et al., 2011b). Specifically, GORMAS (Guidelines for ORganizational Multi-Agent Systems) proposes a set of activities for the analysis and the design of VOs. These guidelines cover the requirement analysis, the structure design and the design of the organization-dynamics. Software

Evaluation

Bringing agent technology to real domains such as industry or business entails the development of efficient platforms and infrastructures capable of engineering open distributed systems. Efficiency is one of the main requirements that have motivated the design of MaNEA. To this goal, MaNEA is based on a tracing service, which has been implemented following a publish/subscribe metaphor. Traditionally, Norm-Enforcing Architectures have been built using overhearing approaches. Overhearing is

Conclusions and future works

In this paper, we have described a Norm-Enforcing Architecture (MaNEA) that has been developed considering the facilities provided by the Magentix2 platform. The main aim of MaNEA is to overcome problems of existing proposals on norm enforcement. MaNEA enforces norms providing support to those agents that are not endowed with normative reasoning capabilities. In addition, the generation of events for informing about sanctions and rewards allows norm-aware agents to use this information for

Acknowledgement

We acknowledge ITMAS 2011 as the forum in which the main ideas behind this paper were preliminary discussed. This paper was partially funded by the Spanish government under projects CONSOLIDER-INGENIO 2010 CSD2007-00022, TIN2009-13839-C03-01, TIN2012-36586-C03-01 and by the FPU grant AP-2007-01256 awarded to N.Criado. This research has also been partially funded by the Generalitat de Catalunya under the grant 2009-SGR-1434.

References (52)

  • Boella, G., Van der Torre, L., 2004. Regulative and constitutive norms in normative multiagent systems. In: Proceedings...
  • R. Bordini et al.
    (2008)
  • H. Cardoso et al.

    Institutional reality and normsspecifying and monitoring agent organizations

    Int. J. Coop. Inf. Syst.

    (2007)
  • Criado, N., Argente, E., Botti, V., 2010a. A BDI architecture for normative decision making (extended abstract). In:...
  • N. Criado et al.

    Open issues for normative multi-agent systems

    AI Commun.

    (2011)
  • Criado, N., Argente, E., Botti, V., 2011b. Thomas: an agent platform for supporting normative multi-agent systems. J....
  • Criado, N., Argente, E., Botti, V., 2011c. Towards norm enforcer agents. In: Proceedings of the International...
  • Criado, N., Argente, E., Garrido, A., Gimeno, J.A., Igual, F., Botti, V.J., Noriega, P., Giret, A., 2010b. Norm...
  • Criado, N., Julián, V., Botti, V., Argente, E., 2010c. A norm-based organization management system. In:Coordination,...
  • R. Daft

    Organization Theory and Design

    (2003)
  • Daskalopulu, A., Dimitrakos, T., Maibaum, T., 2002. Evidence-based electronic contract performance monitoring. In:Group...
  • de Pinninck, A., Sierra, C., Schorlemmer, M., 2007. Friends no more: norm enforcement in multiagent systems. In:...
  • Dignum, V., Dignum, F., 2002. Towards an agent-based infrastructure to support virtual organisations. In: Proceedings...
  • Dignum, V., Vázquez-Salceda, J., Dignum, F., 2005. Omni: introducing social structure, norms and ontologies into agent...
  • J. Elster

    Rationality and the emotions

    Econ. J.

    (1996)
  • Esteva, M., Rosell, B., Rodríguez-Aguilar, J.A., Arcos, J.L., 2004. Ameli: an agent-based middleware for electronic...
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