Simulating an SOA application is one of the most instructive ways to understand its usage. It is crucial to the success of an SOA application because it sheds light on the usage patterns of client requests and partner interactions. These patterns are difficult to determine analytically—simulation is often the best way to discover them. The following sections discuss the two conceptual foundations on which both BPM and SOA lie—Poisson process and discrete event simulation.
Behind the simulations we run in this chapter are the mathematics of Poisson processes and the technique of discrete event simulation. It's impossible to design a successful simulation without having a basic understanding of these concepts.
A Poisson process is the sequence of events over time, occurring at some specified rate, which follows these rules:
It has independent increments. That is, the number of events that occur in one time interval...