Adaptive VoIP Playout Scheduling: Assessing User Satisfaction

Miroslaw Narbutt, Dublin Institute of Technology
Andrew Kelly, Dublin City University
Liam Murphy, University College Dublin
Philip Perry, University College Dublin

Document Type Article

IEEE Internet Computing Magazine, July/August 2005


Delay and packet loss dramatically affect the quality of a voice-over-IP (VoIP) call and depend on the playout buffer scheme implemented at the receiver. The choice of playout algorithm can’t be based on statistical metrics without considering the perceived end-to-end conversational speech quality. The authors present a method for evaluating various playout algorithms that extends the Emodel concept by estimating user satisfaction from time-varying transmission impairments. This article evaluates several playout algorithms and shows a correspondence between their results and those obtained via statistical loss and delay metrics.