Hodnocení kvality IP telefonie v přístupových sítích

Abstract

The aim of the thesis is to describe the possibilities for evaluating the quality of IP telephony in access networks and carry out its own verification of models available on these networks. The first chapter deals with the basic description of access technologies, which are used as media access to the global network and the Internet as a transport network for IP telephony. In the second chapter, the methods used to evaluate speech quality in telecommunication technology are described. I focus on two models for objective assessment PESQ and Aqua, which I use later in the thesis for evaluation. When designing the access network simulation software, I used OPNET simulator in which I created three models in the access network and simulate them in the data flow between the various participants on the basis of prepared profiles. The fourth chapter is divided into two areas. In the first section, the quality telephony networks that are created in the laboratory is tested and it is composed of physical interfaces. Individual technologies and their parameters are simulated using the Linux kernel. The second part of the chapter chapter focuses on practical tests, which took place in the actual operating networks. In the final chapter, the results of various models and technologies are compared.