中央研究院  |  資訊科學研究所  |  多媒體網路與系統實驗室
An Empirical Evaluation of VoIP Playout Buffer Dimensioning in Skype, Google Talk, and MSN Messenger
(NOTE: Sheng-Wei Chen is also known as Kuan-Ta Chen.)

Abstract
VoIP playout buffer dimensioning has long been a challenging optimization problem, as the buffer size must maintain a balance between conversational interactivity and speech quality. The conversational quality may be affected by a number of factors, some of which may change over time. Although a great deal of research effort has been expended in trying to solve the problem, how the research results are applied in practice is unclear.

In this paper, we investigate the playout buffer dimensioning algorithms applied in three popular VoIP applications, namely, Skype, Google Talk, and MSN Messenger. We conduct experiments to assess how the applications adjust their playout buffer sizes. Using an objective QoE (Quality of Experience) metric, we show that Google Talk and MSN Messenger do not adjust their respective buffer sizes appropriately, while Skype does not adjust its buffer at all. In other words, they could provide better QoE to users by improving their buffer dimensioning algorithms. Moreover, none of the applications adapts its buffer size to the network loss rate, which should also be considered to ensure optimal QoE provisioning.

Related paper:
- Tuning the Redundancy Control Algorithm of Skype for User Satisfaction
- Quantifying Skype User Satisfaction


Materials
Citation
Chen-Chi Wu, Kuan-Ta Chen, Chun-Ying Huang and Chin-Laung Lei, "An Empirical Evaluation of VoIP Playout Buffer Dimensioning in Skype, Google Talk, and MSN Messenger," In Proceedings of ACM NOSSDAV 2009, 2009.

BibTex
@INPROCEEDINGS{wu09:playout,
  TITLE      = {An Empirical Evaluation of {VoIP} Playout Buffer Dimensioning in {Skype}, {Google Talk}, and {MSN Messenger}},
  AUTHOR     = {Chen-Chi Wu and Kuan-Ta Chen and Chun-Ying Huang and Chin-Laung Lei},
  BOOKTITLE  = {Proceedings of ACM NOSSDAV 2009},
  YEAR       = {2009},
  X_TAG      = {mmsys}
}