Scalability video data distribution using cache terminal for multi-quality video service

In the Video-On-Demand (VOD) services, low resolution video data is suitable for contents searching; on the other hand, high resolution video data is expected for browsing. Even if the client has already received low resolution video data as search results, the traditional simulcast method have to send whole high resolution video data which includes same information with low resolution video data. To decrease the traffic between VOD serve and the clients, there are two different approaches: one is introduction of cache servers between VOD server and clients, to decrease the non-essential transfer of VOD server. Another is the scalability video encoding to remove the non-essential transfer by utilization of pretransferred low resolution video data. In this paper, we analyze these two approaches and show the suitable conditions.