Performance Evaluation of Heterogeneous Network Scenarios

Packet loss, delay and jitter degrade the quality of services like VoIP (Voice over IP) or Video Streaming over IP networks. In real networks, an experimental measure of these parameters is fundamental in the planning process of new services over novel network infrastructures. Furthermore, currently networks are complex heterogeneous systems (in terms of access network technologies, end-users’ devices, Operating Systems and finally end-users’ application). This heterogeneity exacerbates even more the need of a real assessment of the Quality of Service metrics. Stepping fro this consideration, in this Chapter we provide an empirical performance study of real heterogeneous wireless network with respect to delay, jitter, throughput and packet loss, in UDP and TCP environments, by using the innovative tool D-ITG (Distributed Internet Traffic Generator). We also use the concept of “Service Condition” as a mechanism to cope with issues related to dynamically changing network service scenario and to formally define a parametric and systemic approach to the performance evaluation. Results presented in this Report can be used as performance references for development of wireless communication applications over multi-service heterogeneous networks. Indeed, we perform a large set of measurements with a wide set of hardware. Then we take the results of our measurements and by analyzing the similarities and the differences we understand what we can generalize and what not. We investigate the impact of mechanisms and protocols on the performance metrics and we try to prove which protocol element is a limiting factor or which devices characteristics affect the measured metrics. In addition, thanks to the wide range of provided results (as well as the public traffic traces, available on request), a reader could actually make use of the information provided in this Report for his purposes. More precisely, this Report presents results of our performance evaluation activities in the following scenario: