Simulated performance of VoIP using DCCP CCID2 over large delay link networks
Shahrudin Awang Nor, Suhaidi Hassan, Omar Almomami · Universiti Utara Malaysia Institutional Repository (Universiti Utara Malaysia) · 2008
DCCP is gaining popularity as a new transport protocol for sending streaming multimedia contents in the Internet nowadays. As it is a new unreliable transport protocol which has built-in congestion control, DCCP ensures that there is no bandwidth monopoly by certain transport protocol.UDP has been proven that can eat up all the available bandwidth in the Internet while competing with other transport protocols such as TCP in carrying streaming audio and multimedia traffic in many situations. In this paper, we show that the performance of VoIP using DCCP is significantly affected by the size of initial slow-start threshold (ssthresh) over large delay links. All TCP congestion control implementations are required to support slow-start threshold implemented in DCCP’s TCP-like congestion control (CCID2). From our experiments, we found out that too small initial slow-start threshold value for large delay link makes the traffic throughput sent using DCCP requires longer time to become stable. The selection of suitable value of initial slow-start threshold is then vital for the performance of VoIP using DCCP over large delay link networks.