Content-Aware Selective Retransmission Scheme in Heavy Loaded Wireless Networks (original) (raw)

Streaming media is becoming increasingly prominent on the Internet, although multimedia applications have very stringent bandwidth, delay and loss requirements. In mobile environment the limited bandwidth and the higher error rate arise as an obstacle of its popularity. In many cases retransmission-based error recovery can be an attractive solution to improve the quality of the video stream, because it requires minimal network bandwidth and processing cost. In this paper we propose a content-aware selective retransmission scheme which allows the retransmission of all packets when the risk of congestion is low, but as it rises the retransmission is disabled step-by-step, but not all at once, in order of packet importance. In this work the heterogenity of H.264 streams were utilized for the determination of packet importance. The advantage of this transmitter controlled procedure is that all the needed information is available at the source due to DCCP transport protocol and its congestion control algorithm. The effectiveness of the proposed method was examined in Ns2 network simulator.