Rate-based end-to-end congestion control of multimedia traffic in packet switched networks

摘要

This paper proposes an explicit rate-based end-to-end distributed congestion control mechanism for multimedia traffic in packet switched networks such as the Internet. The network is viewed as a set of sources distributed with feedback from respective destinations and it is modeled as a nonlinear system. The congestion is controlled by adjusting the transmission rates of the sources in response to the feedback information from destination such as the buffer occupancy, packet arrival and service rate, so that a desired performance referenced to as a quality of service (QoS) can be met. The QoS is defined in terms of packet loss ratio, transmission delay, system power and fairness. The performance and stability of the system is analyzed mathematically. The proposed scheme has been implemented in the NS-2 simulator. Simulation results demonstrate the performance of the scheme to be in agreement with mathematical analysis. The proposed scheme is shown to provide considerable improvements in terms of the QoS metrics over New-Reno TCP (a variant of AIMD: additive increase multiplicative decrease) technique. Since it is end-to-end, no additional router support is necessary, and the proposed methodology can be readily applied to today's Internet, as well as for real-time video and voice data transfer in unicast networks. Finally some information is given as its overhead needed for the proposed scheme.