Measurement-Based Traffic Characterisation Techniques
Gergely Seres · 2008
This dissertation aims at investigating the capabilities of traffic characterisation techniques in a number of research and real-life applications. From the sizable research areas in this field, this work addresses the measurementbased construction of traffic models, the creation of measurement-based resource requirement estimators, their applications in node level measurementbased admission control and network performance management, and the development of architectures for traffic generator tools specialised for the verification of measurement-based traffic characterisation techniques. The first area of study is an empirical stochastic network operating system model that provides a solution for simulation-based studies requiring high statistical accuracy on the packet level. The model can interoperate modularly with all Layer 4 protocols of the TCP/IP protocol stack, with ATM and Ethernet in Layer 2 and with arbitrary Layer 1 protocols, and it can be parametrised with a measurement-based procedure. In the second part of the study, an analytical investigation is carried out to arrive at expressions for the optimal, direct computation of the equivalent capacity and the buffer requirement of conversational or streaming voice and video traffic flows. The results are made part of a general methodology for reformulating earlier network performance estimators into resource requirement estimators. In the third part of the work, the achieved results are applied in the field of adaptive network control solutions in the form of a measurement-based CAC scheme and a network performance management architecture, both based on the distributed, on-line computation of the novel equivalent capacity estimator. The fourth part of the work deals with the verification of the proposed solutions through a precision traffic generator architecture which can produce traffic-model-driven, accurately timed test traffic patterns through the use of a novel time-shifted precision packet generation process for UNIX-type operating systems.