Decision support for cooperative QoS management

Cooperative QoS management is a new quality-of-service management scheme which is based on QoS agents distributed within a system and cooperating with each other to provide the QoS negotiated with users, thereby ameliorating the overall system's resource usage and decreasing the communication costs. During their operations, agents have to take decisions in order to react on QoS violations, initiate QoS renegotiation processes or react on renegotiation requests from other QoS agents. In this paper, we present two tools which support cooperating QoS agents in their decision processes: a model called the "quality of operation", based on a mathematical formula, and an approach based on a new variant of stochastic Petri nets, the so-called controlled stochastic Petri nets.