In addition to text, images, animation, information on the web can also be placed on a sound and dynamic image files, providing viewers appreciate online function, a technique called VOD (Video-On-Demand) - VOD technology, users can be free from the constraints of time, space, watching demand instant play, online through the Internet. Either sound or video files, are the file format, the VOD In order to overcome the problem of time-consuming file transfers using streaming technology as a means of transmission, so that it can achieve a true on-demand to watch and do not need to wait for the file to download, as long as the file is open, read, transfer, synchronized playback. VOD VOD technology is applied in many places, such as real-time stock quotes, Jiepan Analysis, distance learning, e-Learning, e-commerce e-Commerce, online MTV, KTV, internal bulletin broadcast, training, etc. VOD VOD technology advantage can provide dynamic information update, more interactive effect. In addition, the less the reset trouble, more cost savings and improve convenience. Even ISP or ICP industry can integrate streaming technology with software and hardware, and multimedia information network switching center, or multimedia the ASP to provide bandwidth sharing, hosting, data interchange and software rental service, which is calledthe Multimedia IDC.