Fuzzy characterization and control of QoS in multimedia cell-based networks

In cell-based networks carrying multimedia traffic, some types of traffic, such as voice and video, are too complicated to be captured in precise mathematical formulations for modeling and control. This paper presents a fuzzy mathematical characterization of such complex traffic processes. In particular, the QoS of each individual traffic type is modeled as a fuzzy quantity, so as to capture the associated descriptive uncertainty and vagueness. Each QoS is modeled by a Gaussian possibility distribution. We show that several such possibility distributions, when aggregated (superposed), produce another Gaussian possibility distribution. Fuzzy characterization is used as the basis for developing an intelligent mechanism to enforce and control the incoming QoS of each type of traffic at an access point. The fuzzy access controller presented here uses the Sugeno inference method with a fuzzy linear output.