Implementation and evaluation of video transfer system over Internet with congestion control based on two level rate control

Recently, video data transfer is one of the major types of traffic over the Internet. However, it is impossible for the current Internet to guarantee the quality of service (QoS) for video transfer and an influx of a large amount of video data into the Internet may cause serious network congestion. To resolve these problems, we previously proposed a protocol using congestion control based on rate control of the video coding level and data transfer level, and evaluated this protocol using software simulation. However, in order to apply this protocol to real video communication, our previous protocol had some problems, mainly with regard to efficiency. In this paper we present an improved specification of a video transfer protocol with two level rate control. This paper also describes the results of implementation and evaluation of an actual video transfer system using our improved protocol, and a commercial video tool with H.261 encoding. The results show our protocol can transfer video data effectively and fairly through a congested network.