Multipath Transmission Techonology For Real-time Streaming Media Over Heterogeneous Wireless Networks

The popularity of smart phones and the development of heterogeneous wireless network have promoted the booming of real-time streaming media service.How to use multiple wireless network interfaces of smart phones to concurrently transmit data using multi-path transmission technologies to provide high-quality transmission service for real-time streaming media service is a hot issue in the industry.Distinguished from traditional network services,real-time streaming media service is characteristic of low latency,high stability,and other requirements.However,the existing multi-path transmission protocol can not meet the requirements of real-time streaming media.Based on the requirements of real-time streaming media,this thesis studies the multi-path transmission protocol for real-time streaming media to improve the transmission quality of real-time streaming media service.For the fully reliable and ordered transmission mechanism and the additive increase multiple reduction(AIMD)based congestion control mechanism,existing multi-path transmission protocol will reduce real-time streaming media transmission quality.Aiming to resolve this problem,the thesis proposes multi-path transmission protocol for real-time streaming media,Real-Time Streaming Media Multipath Transport Control Protocol(RTSM-MTCP).RTSM-MTCP resolves the problem of excessive time delay caused by a completely reliable and ordered transmission mechanism through a partially reliable and ordered transmission mechanism based on real-time streaming media delay constraint awareness.And it also resolves the problem of large throughput fluctuations and large delay jitter caused by the AIMD congestion control mechanism using the rate control mechanism of TCP Friendly Rate Control(TFRC)algorithm and Spike's packet loss discrimination algorithm.The research results show that RTSM-MTCP can obtain relatively stable throughput and smaller delay,which can effectively improve the transmission quality of real-time streaming media.Based on RTSM-MTCP,this thesis further studies the traffic allocation problem in multi-path transmission.By analyzing the transmission process based on RTSM-MTCP,an end-to-end delay model for real-time streaming media data transmission is constructed.Based on the end-to-end delay model and the delay constraint of real-time streaming media,the thesis proposes an end-to-end delay-based traffic allocation algorithm,RTSM-MTCP Delay Aware,RTSM-MTCP-DA,to minimize the end-to-end delay of media data transmission of real-time streaming.The research results show that the proposed RTSM-MTCP-DA algorithm can effectively reduce the end-to-end delay of data transmission,improve the system's goodput,and further improve the real-time streaming media transmission quality.The proposed RTSM-MTCP transmission protocol and RTSM-MTCP-DA traffic distribution algorithm proposed in this thesis can be applied to real-time streaming services and have practical value for improving the transmission quality of real-time streaming media.