A QoE-aware transmission mechanism for interactive IPTV over IEEE 802.16 networks

In this paper, we study Quality of Experience (QoE) in the transmission of interactive IPTV (IIPTV) over IEEE 802.16 networks where the video traffic is coded using Scalable Video Coding (SVC). The proposed mechanism includes two major algorithms. 1) A QoE-based layer selection namely QoE-LVT which decides on the appropriate SVC layers that should be transmitted from the server to each subscriber. For this purpose, the loss rate experienced by each subscriber is returned to the server via an uplink connection. Given this feedback and also some other information internally available, the server estimates the QoE of the user using Neural Network-based learning functions. Then the appreciate decision for excluding the layers which cause QoE deterioration is taken. 2) A priority-based scheduling in the IEEE 802.16 MAC layer which assigns priority to each SVC layer according to the impact of the layer on the user's QoE. We provide some cross-layer interaction to enable distinguishing among different SVC video layers (i.e., base layer and two enhancement layers) in IEEE 802.16 MAC. Results of extensive simulations using NS-3 simulator confirm that compared to previous works our proposed mechanism improves QoE of both fixed and mobile users.