Source And Channel Rate Control For Streaming Multimedia

As the key components of adaptive multimedia streaming, source and channelrate control can help the multimedia application achieve the optimal playback qualityunder various network conditions. In this thesis, we focus on joint design of source andchannel rate control for streaming multimedia, which aims to improve the playbackquality of the application, and optimize the overall system performance through thecollaboration of source rate control and channel rate control.In the first part of the thesis, we discuss the joint design algorithm for streamingmultimedia over the Internet. To make it possible for the transport layer to supportthe QoS requirements of the application, we propose a QoS-aware congestion controlmechanism - TFRCC. TFRCC can be aware of the QoS requirements of the appli-cation in a real-time manner, and it allows the send rate to temporarily violate TCP-friendliness when necessary to assure the continuous playback of the application. Nev-ertheless, the long-term TCP-friendliness of the transport protocol can be preserved byintroducing a rate compensation algorithm. TFRCC can provide better QoS support forthe application, while maintaining the long-term TCP-friendliness and not degradingthe performance of the overall network.Then based on TFRCC and the cross-layer design principle, we propose a jointdesign algorithm of source rate control and congestion control, which allows sourcerate control at the application layer and congestion control at the transport layer tocommunicate and collaborate more tightly with each other. This joint design algorithmcan help the application achieve the optimal trade-off between the constraints from thenetwork (i.e. the fairness, and the responsiveness of the transport protocol) and the QoSconstraints from the application layer, thus optimize the overall system performance.Furthermore, we extend the above joint design algorithm for the wired channels tothe wireless scenario. By generally considering the network constraints from the trans-port layer and the QoS requirements from the application layer, and taking advantage ofMAC layer information, we propose a cross-layer design approach for wireless videostreaming. Our approach can avoid the throughput degradation caused by transmissionerror of the wireless channel, and can significantly improve the playback quality ofwireless video streaming through the joint design mode.In the last part of the thesis, we discuss the problem of joint source and channelrate control for streaming multimedia over QoS-assured channels. We formulate theproblems of VBR video streaming over CBR and VBR channels as a unified form -optimal control of discrete linear time-delay system. Then the optimal control can beachieved by using discrete maximum principle. The main contribution of our workis that it provides a solution with much lower complexity, and the solution has nospecial requirements for the parameter setting, thus broadening the scenario where thealgorithm can be applied.