ABSTRACT
In this manuscript, methods for modelling and parameter assessment of unconstrained and constrained videoconference traffic are proposed. In the case of unconstrained traffic the encoder operates in an independent of the network mode (open-loop) while in constrained traffic the encoder has knowledge of the networking constrains and operates using rate-control algorithms (in the loop). The analysis of extensive data that were gathered during experiments with popular videoconference terminals, as well as of traffic traces available in literature, suggested that while the unconstrained traffic traces exhibited high short-term correlations, the constrained counterpart patterns appeared to be mostly uncorrelated, in a percentage not affecting queueing. On the basis of these results, this study discusses methods for accurate modelling and analytical treatment of both types of traffic. Extensive model-based queuing results, in single-source and multiplexed environments, using continuous methods, compared to trace-driven results, confirm the validity of our modelling proposals.
