Shmeleva T. Efficacy evaluation of switched Ethernet via parametrical Petri nets

On the base of the theory of classical and colored Petri nets parametrical models of tree-like telecommunication structure with an arbitrary number of attached devices were introduced for the first time. But it was shown that the model is not a live Petri net because it contains deadlocks. Mutual blockings of switches with compulsory buffering of frames that lead to the considerable fall in the network performance were revealed. A parametrical model of switched Ethernet in the form of colored Petri net which consists of a fixed number of nodes was developed. As the result the model is permanent regarding LAN topology, number of attached networking and terminal devices that does not require the modification of its structure and considerably decreases the laboriousness of the model development and the evaluation of the networks efficacy. For the performance evaluation of given switched Ethernet networks the parametrical colored Petri net model was supplied with special measuring fragments. Measuring fragments were constructed for the evaluation of such functional characteristics as the network bandwidth (performance), the frame delivery time, the network response time and so on.