Th`ese de Doctorat de l'université Paris VI Pierre et Marie Curie Mlle ...

Chapter 4
Network Model
Dynamic bandwidth allocation in Quality of Service (QoS) networks is a challenging prob-
lem that has recently been the focus of many researchers. Maximization of total network
revenue and satisfaction of users’ QoS requirements are two important aspects to consider
in resolving such problem.
This Chapter makes the following contributions. First, we describe the network model
and we define the notation for the full comprehension of the problem. Then, we perform
a connections’ classification taking into account the online traffic statistics collected by
ingress routers. This classification is fundamental to our heuristic algorithms, in that it
allows to exploit the unused bandwidth left over by idle and Non-greedy connections to
achieve high network revenue. Finally, we provide a definition of the network extra-revenue
that is expressed in terms of users’ bandwidth utility functions. This definition constitutes
one of the two performance metrics used to evaluate the performance of our bandwidth
allocation algorithms.
This Chapter is organized as follows. Section 4.1 presents a precise statement of the
bandwidth allocation problem. Section 4.2 performs a connections’ classification based on
online measured traffic statistics. Finally, Section 4.3 introduces the network extra-revenue
definition.
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