Performance of VoIP using DCCP over a DVB-RCS Satellite Network

The datagram congestion control protocol (DCCP) is a new IETF-defined transport protocol for Internet multimedia. The DCCP congestion control identifier 4 (CCID4) was specifically designed to support the stream of small packets generated by applications such as voice over IP (VoIP). This uses equation based congestion control. The long round trip delay when the path includes a satellite link could therefore degrade the performance of VoIP. In this paper, we analyze using simulation the performance of VoIP using CCID4 over a DVB-RCS network. We also analyze the different variants of CCID4 that have been proposed. The paper concludes that the current algorithm of CCID4 suffers for paths with appreciable delay when used to support voice calls with a bursty nature. The results show that these effects are only partially mitigated by the currently proposed variants of CCID4.