Accepted paper in the 7th International Workshop on Quality of Multimedia Experience (QoMEX 2015)

Video users in a multicast group may be highly heterogeneous in terms of individual channel conditions and requirements for video transmission, making it a challenging task for the network to optimally configure the resource management.
In this paper, we consider a mathematical model for the choice of the optimum number of transmission opportunities, based on a Markov chain representation of the wireless channel, where each channel state is associated to a different quality corresponding to a choice of video layer and Modulation and Coding Scheme (MCS).
In case of multicast transmissions, the selection of the video layer is based on the aggregate channel conditions of all users and a collection of coordination rules.
We evaluate how the cross-layer optimisation performs and also define a taxonomy of user quality perception. We further investigate how users’ satisfaction levels vary in the multicast session.
Performance evaluation results show that cross-layer optimisation significantly outperforms sequential and independent scheme for multicast video transmissions, conforming the strong need for cross-layer solutions in video transmission, however, this improvement is heavily related to the resource allocation policy of the operator.

Find the paper here.