Performance analysis of an integrated video/data transport mechanism with built-in congestion control

The authors consider a possible integrated video/data multiplexer where conference video and plant file transfer services are provided. The link bandwidth is divided into a number of fixed-bandwidth channels. The video signals are encoded in such a way that the coded information is transmitted over multiple channels, where the primary channel transmits the highest priority information for good quality video, and the remaining channels, with decreasing priorities, transmit information for enhancing the quality of the video. Due to the separability of video signals into multiple bands with different priorities, an existing video call can relinquish use of one or more low-priority channels to make room for more video calls if congestion occurs. A data transport service, e.g. file transfer, is provided through the unused portion of the link bandwidth. Data files are enqueued for available channels, and transmission of a file is preempted if a new video call requires use of that channel; such preemption will necessitate retransmission of the file