Segment Scheduling Scheme for Efficient Bandwidth Utilization of HTTP Adaptive Streaming in Multipath Environments
Heekwang Kim, Kwangsue Chung · IEEE Access · 2019
HyperText Transfer Protocol (HTTP) adaptive streaming has been receiving attention to provide efficient video streaming services by adaptively adjusting the transmission rate. With increased demand for high-quality video streaming, since mobile devices are now equipped with multiple wireless interfaces connected to different networks (3G/4G or Wi-Fi), one possible solution to provide a better quality of experience (QoE) is to use multipath-based transmission schemes. In conventional HTTP adaptive streaming systems, the segment request policy initially operates in a buffering state and switches to a steady state once the playout buffer reaches a threshold. In the steady state, the client generates an ON/OFF traffic pattern that degrades bandwidth utilization and user QoE in multipath environments. In this paper, we propose a segment scheduling scheme for efficient bandwidth utilization in multipath environments. In our scheme, we first propose a collective segment request policy to improve bandwidth utilization and reducing the frequency of OFF periods. To improve network responsiveness, we present a method for adaptively adjusting the request interval. Subsequently, we propose a segment scheduler to prevent the out-of-order problem in multipath environments. Finally, a rate adaptation algorithm for the proposed request policy is proposed. Through simulation, we prove that our scheme significantly improves bandwidth utilization and increases the average bitrate.