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This paper studies congestion control schemes for integrated variable bit-rate (VBR) video and data communications, where the quality of service (QOS) of each medium needs to be satisfied. In order to control congestion, we exert here either dynamic resolution control or QOS control. The dynamic resolution control scheme in this paper dynamically changes the temporal or spatial resolution of video according to the network loads. The QOS control scheme here assigns a constant capacity of buffer to each connection and determines the video resolution in order to guarantee the QOS of each medium at the connection establishment. The performance of these schemes is evaluated through simulation in terms of throughput, video frame delay probability distribution, and video frame loss rate. We also examine the effects of priority scheduling and packet discarding on the performance. Numerical results indicate that both dynamic resolution and QOS control attain low delay jitters as well as large video and data throughput. In particular, the QOS control is shown to be more suitable for integrated VBR video and data communications.