Organisational adaptation of multi-agent systems in a peer-to-peer scenario

• Published in: Computing 2011-02, Vol.91 (2), p.169-215
• Main Authors: Campos, Jordi, Esteva, Marc, López-Sánchez, Maite, Morales, Javier, Salamó, Maria
• Format: Article
• Language: English
• Subjects: Adaptation; Agents (artificial intelligence); Agents intel·ligents (Programes d'ordinador); Algorithmics. Computability. Computer arithmetics; Analysis; Applied sciences; Architecture; Artificial Intelligence; Case studies; Computer Appl. in Administrative Data Processing; Computer Communication Networks; Computer Science; Computer science; control theory; systems; Computer simulation; Design; Dynamical systems; Exact sciences and technology; Expert systems; Information Systems Applications (incl.Internet); Intelligent agents (Computer software); Intel·ligència artificial; Mathematics; Methods of scientific computing (including symbolic computation, algebraic computation); Multiagent system; Norms; Numerical analysis; Numerical analysis. Scientific computation; Organization theory; Peer to peer computing; Peer-to-peer architecture (Computer networks); Sciences and techniques of general use; Sistemes multiagent; Software Engineering; Studies; Theoretical computing; Xarxes punt a punt (Xarxes d'ordinadors)
• ISSN: 0010-485X; 1436-5057
• DOI: 10.1007/s00607-010-0141-9

Organisations in multi-agent systems (MAS) have proven to be successful in regulating agent societies. Nevertheless, changes in agents’ behaviour or in the dynamics of the environment may lead to a poor fulfilment of the system’s purposes, and so the entire organisation needs to be adapted. In this paper we focus on endowing the organisation with adaptation capabilities, instead of expecting agents to be capable of adapting the organisation by themselves. We regard this organisational adaptation as an assisting service provided by what we call the Assistance Layer . Our generic Two Level Assisted MAS Architecture (2-LAMA) incorporates such a layer. We empirically evaluate this approach by means of an agent-based simulator we have developed for the P2P sharing network domain. This simulator implements 2-LAMA architecture and supports the comparison between different adaptation methods, as well as, with the standard BitTorrent protocol. In particular, we present two alternatives to perform norm adaptation and one method to adapt agents’ relationships. The results show improved performance and demonstrate that the cost of introducing an additional layer in charge of the system’s adaptation is lower than its benefits.