A TYPICAL FUZZY CONTROLLER

Анотація

In the article was made an analysis of the Bandwidth capacity data, which are indicating that when using the PI-method, the bandwidth capacity of channel with overload decreases with increase of the UDP-stream density.

A typical controller based on fuzzy logic (Fuzzy Logic Controller, FLC) is described in the article. Functional scheme of the FLC is presented. The structure of fuzzy controller is given. The table of fuzzy rules of the controller and its architecture is presented. Experimental data on queue lengths are presented. A review of controllers based on REM-method of active queue management (FREM, STREM, FEM) is given and conclusions concerning their impact on the router parameters are made.

It is proved that when the PI-method is used, the bandwidth capacity of channel with overload decreases with increase of the UDP-stream density. The RED-method has more stable bandwidth capacity when the UDP-stream density is varied. However, the highest and the most stable results are observed when using the FLC controller. The main advantage of the FLC-controller is that the length of the queue is stable with variation of the network parameters.