ABSTRACT

In this chapter and in the next two chapters, we will consider the notion of fluid models or fluid queues. However, there is very little commonality between what is called fluid queues here and what we will call fluid queues in the next two chapters. In fact they have evolved in the literature rather independently, although one could fathom putting them together in a unified framework. We will leave them in separate chapters in this book with the understanding that in this chapter we are interested in the fluid limit of a discrete queueing network whereas in the next two chapters we will directly consider queueing networks with fluid entities (as opposed to discrete entities) flowing through them. Another key distinction is that the resulting fluid network in this chapter is deterministic lending itself straightforward ways to determine stability of queueing networks, develop performance measures approximately, as well as study transient and time-varying queues. In the next section, we will study stochastic fluid networks.