实时多媒体单播传输的拥塞控制研究

Research on Congestion Control of Real-Time Multimedia Unicast

简要分析了应用于实时多媒体传输的、以RAP为代表的仿TCP速率控制方案的不足,提出了一种TCP友好的、基于RTCP反馈的拥塞控制机制,该机制使发送速率的变化更为平滑,更适合于注重回放质量的实时多媒体应用.与RAP的比较实验显示,在瓶颈链路带宽、时延和包丢失率变化情况下,该机制具有比RAP更好的TCP友好性.

This paper makes a brief analysis on the disadvantage of TCP-like rate control scheme for real-time multimedia service,and presents a RTCP-based congestion control mechanism which is stable and TCP-friendly.This mechanism makes the rate vary smoothly and it is fit for real-time multimedia applications.Lastly it makes a simulation through NS to evalue the performance of RAP and RCC,which lays a strong emphasis on the study of TCP-friendliness.The experimental results show that RCC mechanism,in most of scenarios:bottleneck link bandwidth varied,delay varied and loss ratio varied,is more TCP-friendly by contrast with RAP.