Home // International Journal On Advances in Telecommunications, volume 4, numbers 3 and 4, 2011 // View article
Authors:
Tibor Gyires
Yongning Tang
Aishwarya Mishra
Olusegun Obafemi
Keywords: Quality of Service, Quality of Experience, Playout Buffer, Impact Factor, Statistical Analysis, VoIP
Abstract:
The speech quality of Voice over IP (VoIP) applications can be assessed subjectively as Quality of Experience (QoE) and objectively as Quality of Service (QoS). QoE is multifaceted, which ties together user perception and expectations to application, network performance, and various voice data processing (e.g., codec) and streaming (playout buffering) methods. Most of prior work focuses on understanding the impact of network performance on QoE, but not explicitly describing how playout buffer affects user satisfaction or QoE assessment. Towards this goal, this paper presents a statistical analysis of the correlation among QoE assessment, QoS measurement, and the impact of playout buffer on QoE assessment. In this paper, we first identify QoE as a function along two dimensions of network loss and delay to understand how different network factors as well as playout buffer affect QoE assessment. Then, we propose a new performance metric called playout buffer QoE impact factor (IFQoE) to explicitly valuate the effectiveness of playout buffer in terms if its contribution to QoE improvement. Finally, we validate IFQoE to statistically show its accuracy in terms of its strong correlation with the results of QoE assessment. All our study is based on extensive simulations using various emulated or real network scenarios. Our simulation results show that IFQoE can accurately evaluate the impact of playout buffer on QoE assessment using directly measurable network performance metrics.
Pages: 229 to 239
Copyright: Copyright (c) to authors, 2011. Used with permission.
Publication date: April 30, 2012
Published in: journal
ISSN: 1942-2601