A Service-Based Agent System Supporting Mobile Computing

Machine Operating System Communication Facility Mobile Agent System ______________________________________________________________________________________ 15 ices to mobile agents. Services can be e.g. clients for database accesses, mail servers, or any other non-agent applications such as the Common Object Request Broker Architecture services (CORBA, [COR02]). They can consist of simple classes, but are not restricted to them. On the one hand, a service can be a full package with many internal objects. On the other hand, such a service agent can be a simple wrapper to some legacy application interfaces. Decisive for mobile agents is security, because they are executed in various agent systems and hence, cannot be considered trustworthy. Once a mobile agent enters an agent system, it can only process its internal data and call services controlled by the agent system. Interaction with other agents or the usage of system/host resources can only be achieved through system agents or the agent system. The general life cycles of a mobile agent is shown in figure 2-8. After configuration and creation, an agent executes its code and may switch to suspend state or the service look up state, which are both supported by the agent system. During execution, mobile agents can change their physical location through migration. They can terminate at any host, except if results have to be returned to the origin.