This paper describes a streaming architecture simulation model above Network Simulator 2 (NS2) which allows to define specific transport properties. Multimedia contents are specific because they are time-dependent and they can undergo small deterioration if necessary. We simulate such a congestion control that has the ability to decrease the multimedia quality in case of network congestion in order to decrease packet losses and packet delivery delays. We integrate this video congestion control inside DCCP (Datagram Congestion Control Protocol) and TFRC (TCP Friendly Rate Control). The transcoding of the multimedia contents is realized thanks to the NetMoVie simulation model which is an RTP mixer. We compare the adaptive transport solution to the classic transport solution without any adaptive mechanism. The Peak Signal-to-Noise Ratio (PSNR) of the received multimedia contents is measured and compared for better visualization.