Voice transmission over IEEE 802.11 networks: main issues and restrictions

ABSTRACT

This work analyzes the voice communication over IEEE 802.11 networks (VoWiFi). It empirically characterizes the transmission problems of VoWiFi and describes scenarios where it could be used over the existing network technologies. The two major problems found were: the excessively long handoffs and the occurrence of bursts. We conclude that is feasible to use VoWiFi if, during a voice call, mobility is kept low, signal strength is high enough and the network capacity is not exceeded.Este trabalho faz uma avaliação da comunicação de voz sobre redes IEEE 802.11 (VoWiFi). Para isto, caracteriza empiricamente os problemas de transmissão e aponta cen´rios em que a implantação de VoWiFi é vi´vel utilizando-se as tecnologias atualmente disponĩveis. Os dois principais problemas encontrados foram: a longa duração das migrações (handoffs) e a ocorrência de tr´fegos em rajada. Concluĩmos que, com as tecnologias atuais, a utilização de VoWiFi é vi´vel desde que, durante uma chamada, a mobilidade seja baixa, a qualidade do sinal seja suficientemente alta e que a capacidade de transmissão da rede não seja excedida.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design
          Subjects: Wireless communication

Additional Classification:
  H. Information Systems
  H.4 INFORMATION SYSTEMS APPLICATIONS
      H.4.3 Communications Applications

General Terms:
Experimentation, Measurement, Performance

Keywords:
IEEE 802.11, VoIP, VoWLAN, VoWiFi, Wi-Fi