Date Added: Sep 2009
In this paper, the perceived quality of VoIP communications is studied. The distributions of the number of consecutive received and lost packets, respectively named gap and burst, of a VoIP communication are modeled with discrete two-state and four-state Markov chains. Algorithms for estimating the transition probabilities between states and from these, the packet loss rate and the respective gap and burst length distributions, are described. Through a study of monitored VoIP calls, it is shown that these models can adequately represent the geometric-type decay of these distributions and that although two-state model performs well for homogeneous losses, for non-homogeneous losses the four-state model fits better.