Content and buffer status aware packet scheduling and resource management framework for video streaming over LTE system

With the development of the video encoding and wireless communication technologies, DASH (Dynamic Adaptive Streaming over HTTP) services have an increasing and great share of all the mobile services. However, we find some problems which still need to be addressed for DASH service optimization: (1) the limitation of the video segment representations cannot keep pace with the change of wireless channel states; (2) the characteristics of the video transmission have been not fully utilized in current DASH services; and (3) long interruption time will yield poor QoE (Quality of Experience). To solve these problems, we build a new transmission architecture by modifying the traditional TCP transmission flow. We first add a TCP (Transmission Control Protocol) proxy responsible for discarding the expiry packets automatically before putting them into the TCP sending window and then build a "ACK (acknowledgement) reconstruction module" to reconstruct the received ACK for concealing the packets discarded by the packet scheduler. Based on the new framework, we explore the interdependence among all the packets from the encoder to indicate the importance of each packet and update the interdependence relationship of every scheduling period based on the feedback ACK information. At MAC (Media Access Control) layer, a buffer status estimation module is employed to estimate the client buffer and playback information, which can be used to calculate the packet urgency. Then, a cross-layer design, which consists of an application layer of media server and client, TCP layer, MAC layer, and physical layer, is formulated and the packet scheduling and resource allocation can be jointly optimized. At client, through the analysis of the status of client buffer and MAC queue, an adaptive segment request scheme is developed to determine how and when to send the segment request. Simulation results show that the proposed algorithms can efficiently improve the received video quality as well as the playback continuity compared with other existing algorithms.