AVALIAÇÃO DE PARÂMETROS DE QOS NA TRANSMISSÃO DE VOZ SOBRE IP / ASSESSMENT OF QOS PARAMETERS IN VOICE OVER IP TRANSMISSION

AUTOR(ES)
DATA DE PUBLICAÇÃO

2004

RESUMO

This work presents a study aiming at to establish a methodology for sizing a VoIP system, focusing, in particular, the sizing of a statistical multiplexer. We apply existing models and results for the general problem of the statistical multiplexer to the specific case of a VoIP system, taking in account the characteristics of the traffic, the requirements of QoS and the principles of the architectures Intserv and Diffserv. For this, we present a summary of the VoIP technology, including its requirements of quality and the protocols appropriate to carry this type of media in the Internet. We discourse on the usual mechanisms of traffic control in packet networks with QoS, as well as on the Architectures of QoS defined by the IETF. A revision of traffic models and applicable models to the analysis of statistical multiplexers, with prominence for the fluid model applied to the description of the traffic generated for a homogeneous aggregate of voice sources, is presented. Besisdes, a comparative study of behavior gotten analytically with those gotten by means of simulation is made. The influence of the coder and parameters as so packet size is investigated, revealing the difficulty in finding an analytical model capable to take in account, with precision, the different formats of the VoIP system. Finally, we establish a scenario for application of the models to a VoIP system.

ASSUNTO(S)

voice telefonia voz telephony

ACESSO AO ARTIGO

Documentos Relacionados