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

Chapter 1
Introduction
The Internet was originally designed to support mainly best-effort services like file transfer,
electronic email and remote login. However, with the emerging and widespread use of
multimedia applications, Internet users are now exchanging through the network real-time
traffic like voice and video. Multimedia applications usually require Quality of Service
(QoS) guarantees from the network, in terms of throughput, packet loss, delay, and jitter.
Several approaches have been proposed to support QoS in communications networks,
such as network resource reservation [18, 19], admission control [20, 21, 22, 23], scheduling
mechanisms [24], service differentiation at network nodes [25] and dynamic bandwidth
provisioning [1, 2, 4, 5, 6, 7, 17].
Efficient dynamic resource provisioning mechanisms are necessary to the development
and automation of Quality of Service networks. In communication networks, resource allo-
cation is performed mainly in a static way, on time scales on the order of hours to months.
However, statically provisioned network resources can become insufficient or considerably
under-utilized if traffic statistics change significantly [1].
A key challenge for the deployment of Quality of Service networks is the development
of solutions that can dynamically track traffic statistics and allocate network resources
efficiently, satisfying the QoS requirements of users while aiming at maximizing, at the
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