Assessment of VoIP quality over Internet backbones

Proceedings - IEEE INFOCOM - Tập 1 - Trang 150-159 vol.1
A.P. Markopoulou1, F.A. Tobagi1, M.J. Karam2
1Department of Electrical Engineering, University of Stanford, Stanford, CA, USA
2Route Science Technologies, Inc., San Mateo, CA, USA

Tóm tắt

As the Internet evolves into a ubiquitous communication infrastructure and provides various services including telephony, it has to stand up to the toll quality standards set by traditional telephone companies. Our objective is to assess to what extent today's Internet meets this expectation. Our assessment is based on delay and loss measurements taken over wide-area backbone networks, considers realistic VoIP scenarios and uses quality measures appropriate for voice. Our findings indicate that although voice services can be adequately provided by some ISPs, a significant number of paths lead to poor performance even for excellent VoIP end-systems. This makes a strong case for special handling of voice traffic on those paths. Even on the good paths, rare loss events can occasionally cause perceptible degradation of voice quality. Finally, the appropriate choice of the playout buffer scheme for each path was found to be of critical importance for the perceived quality.

Từ khóa

#Internet telephony #Spine #Delay #Telecommunication traffic #Loss measurement #Web and internet services #Degradation #IP networks #Communication standards #Communication networks

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