On scalable design of an ATM-based video server

The design issues for a scalable video server is described and, according to these issues, the system architecture of the scalable video servers are proposed. The system uses ATM switching technology to scale up the dimension of the service. There are four major components within the proposed system, namely the server headend control (SHC) unit, the stream router, the video pumping unit (VPU) and distributed storage devices. The functions of each of the components are described and the key components in the system are the stream router and the VPU. Operations and performance limitations on the VPU are given and the result shows that a single storage device can serve only a limited number of video streams. Finally, the paper focuses on the design of the stream router as it is used to connect multiple VPUs for producing guaranteed throughput and bounded delay variance for each video stream.