A behavioral characteristics model for a flexible distributed system

Purpose: With the wide spread of the ubiquitous environment, it is necessary to provide adequate multimedia communication services for various users under various networked environments. In such situations, it is essential to organize multimedia software components dynamically to provide necessary services for effective service provision based on the system's operational environment during the run time of the system. The purpose of this paper is to propose a new scheme for observing and controlling behavior of the QoS-aware agent organization, which provides a flexible QoS control of multimedia service components. Design/methodology/approach: Two models are proposed in this paper: a flexible distributed system (FDS) model and a behavioral characteristics model (BCM), which were applied to the design of network middleware constructed as a QoS-aware agent organization. Experiments were performed using the middleware prototype system. Findings: Results confirmed that the proposed models provide an effective scheme for designers of multimedia communication services. Originality/value: This paper shows that using the FDS model, a multiagent system can be designed and constructed systematically. In addition, using BCM, a multiagent system with flexible QoS control capability can deal with changes of the system's operational situations and thereby maintain the required QoS as well as its behavioral characteristics.