关键词: 监控系统，RTCP，拥塞控制，回环时间，丢包率

Abstract: In order to design a real-time and fluent video surveillance system, this paper presented a new R TCP-based feedback congestion control algorithms to make up for the deficiencies of current way using the congestion control algorithms. In the algorithm, utilizing the key parameters mate the circle time and packet loss rate,forecast the in the feedback TCP packet received from the client, we can network bandwidth to adjust the encoding bit rate of server-side video stream.Experiments show that the algorithm can adjust the video stream encoding bit rate dynamically according to network conditions so that the client can get the smooth real-time video stream.

Key words: Surveillance system, RTCP, Congestion control, RTT, Fraction lost