Playout Buffer Aware Adaptation Scheme over Multi-client LTE Networks

Nowadays, HTTP adaptive streaming (HAS) has become a cost-effective solution in delivering the video content.Different from the one-client HAS, the HAS over multi-client faces many challenges. Due to the lack of the knowledge of the networks, one-client HAS will leads to the low efficiency in utilizing the limited bandwidth over the multi-client circumstance. In this paper, a playout buffer aware adaptation scheme over multi-client (PBMC) LTE networks is proposed to improve the performance of HAS. Firstly, a QoE metric is given that considers both the static quality and the quality smoothness. Secondly, to maximize the QoE, an integer programming problem is formulated. By considering the playout buffer level, the resource requirement, which can guarantee the playout continuity, is formulated as a constraint of the problem. Then, the feasibility of the problem is analyzed. If the problem is infeasible, a method is given to exclude the users as less as possible to obtain the feasibility. When the problem is feasible, a graph model can be constructed based on the resource requirement and the playout buffer level. With the model, the solution can be converted to finding a feasible path with the highest QoE in the graph, which can be solved by employing the dynamic programming. Finally, the simulation results can verify the performance of PBMC in both improving the static quality and guaranteeing the playout continuity.