Communicating Agents in Open Multi-Agent Systems

Abstract

Agents often utilise the services of other agents to perform tasks within multi agent systems. To achieve this, an agent must first locate another agent that has the capability to provide a desired service (i.e. a service provider agent), and then interact with it. To communicate with a service provider, an agent requires information about: 1) the service provider agent's interface; 2) the ontology that defines concepts used by the provider agent; and 3) the agent communication language (ACL) the agent uses so that it can parse and understand the communication. Currently deployed MASs encode the interface description and the ontology within the capability description of a service provider, but assume a common ACL between communicating agents. Middle agents support the discovery of service providers based on the advertised capabilities of the service providers. This advertisement defines the provider agent's interface, and may reference the ontology used by the provider agent. However, the requester agent still requires information about the ACL used by the provider to be able to communicate with it. This paper demonstrates how agents can communicate with each other without making assumptions about the ACLs used, by presenting a template based shallow parsing approach to message construction/decomposition, thus greatly simplifying and improving the robustness of inter-agent communication.