Bit rate throttling algorithm on video over RTP

Live media transmission has acquired a large portion in the realm of internet traffic, much of which is transmitted over best-effort networks. With ever increasing real-time data flow over network, algorithms with efficient utilization of bandwidth and with congestion prevention techniques are becoming integral part of all eminent video transmission systems. While there are bit rate throttling algorithms developed for TCP network, not many algorithms address rate throttling over UDP networks. In this paper, we have explained an algorithm to throttle bit rate of real-time video over UDP network by time slicing video packets. Smoothing Buffer (SB) is placed before network layer to prevent sudden data burst occurrence during high rate video transmission. We have introduced a multimedia timer to continuously observe SB video buffer. The timer is designed to send video packets into the network with timely and efficient manner depending on the SB video buffer size. Video packets are sent into the network in a manner to introduce least possible delay caused by Smoothing buffer introduction. This algorithm is developed by considering H.264/MPEG-4 Part-10 or AVC (Advanced Video Codec) as video codec; RTP on top of UDP as transport layer protocol for video communication and RTSP as network control protocol for end-to-end video session establishment. The aim of this paper is to optimize RTP video packet distribution and prevent uneven data spike occurrence at video sender end. Simulations of this algorithm are performed which illustrates the effectiveness of the algorithm under different transmission video profiles and bit rates.