TR-IIS-01-012    pdffile

An Effective approach to Video Staging in Streaming Applications

Shin-Hung Chang, Ray-I Chang, Jan-Ming Ho, and Yen-Jen Oyang

Institute of Information Science 20, Academia Sinica

Nankang, Taipei 115, Taiwan, R.O.C.

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Due to advances of network technologies, it has become practical to stream the stored video over Internet. Because the video stream is in a compressed format, it is naturally with the variable bit rate (VBR) property and the stream traffic is highly burst. By installing the video proxy between the access network (e.g. local area network, LAN) and the backbone network (e.g. wide area network, WAN), Video Staging is proposed to cache part of a video into the video proxy closed to clients. In this manner, the video can be streamed using a constant-bit-rate (CBR) network service across the backbone WAN and the WAN bandwidth requirement can be significantly reduced.

In this paper, we proposed a new approach, called the caching selected after smoothing (CSAS), to handling Video Staging. The aim of this approach is to integrate the OC algorithm and the video smoothing technique so as to enhance the effectiveness of reducing the WAN bandwidth. The algorithm we proposed is superior to the conventional algorithms in two ways. Our method use less proxy storage to provide video streaming services if the WAN allocated bandwidth is same. With the same proxy storage, our method can also use less WAN bandwidth to provide video streaming services, especially in videos with high variety of bit rate. From the basis of experimental results on several benchmark videos, we conclude that our proposed algorithm is more effective than conventional one by several evaluation indices, including the small proxy storage requirement, the small WAN bandwidth requirement, and the high WAN bandwidth utilization.

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Index terms-- video streaming, constant-bit-rate (CBR), variable-bit-rate (VBR), video staging, video smoothing and video proxy.