Performance of Broadcast and Unknown Server (BUS) in ATM LAN emulation

In this paper, we develop performance models of the Broadcast and Unknown S erver (BUS) in the LANE. The traffic on the BUS is divided into two classes : the broadcast and multicast traffic, and the unicast relay flow, The broa dcast and multicast traffic is assumed to form a Markov Modulated Poisson P rocess (MMPP). The traffic for a particular unicast relay flow is an MMPP a s well. However, the number of active unicast relay flows sojourning on the BUS is determined by a tandem queueing system, where the flow arrival proc ess is Poisson, the address resolution delay is exponentially distributed, and the connection setup delay is three-stage Erlang distributed. The size of data frames in traffic flows is a random variable with three possibile v alues: short, medium, and large. In order to deal with the intractability ( i.e., largeness and stiffness) of the underlying Markov chain, a hierarchic al model is used to decompose the system, With the help of Stochastic Petri Net Package (SPNP), a software package for the automated genaration and so lution of Markovian stochastic systems, and the decomposition method, we st udy the performance of the BUS module under different toads. We also invest igate the effect of address resolution delay and conection setup delay on t he performance of the BUS.