Real-Time Video and Audio IN THE World Wide Web

Abstract

The architecture of World Wide Web (WWW) browsers and servers supports full-file transferfor document retrieval. TCP is usedfor data transfers by Web browsers and their associated Hypertext Transfer Protocol (HTTP) servers. Full-file transfer and TCP are unsuitable for continuous media, such as realtime audio and video. In orderfor the WWW to support continuous media, we require the transmission of video and audio on demand and in real time, as well as new protocolsfor real-time data. We extend the architecture of the WWW to encompass the dynamic, real-time information space of video and audio. Our WWW browser Vosaic, shortfor Video Mosaic, incorporates real-time video and audio into standard hypertext pages that are displayed in place. Video and audio transfers occur in real time; there is no file-retrieval latency. The video and audio result in compelling Web pages. Real-time video and audio data can be effectively served over the present day Internet with the proper transmission protocol. We have developed a real-time protocol called VDP that we specialized for handling real-time video over the WWW.- VDP reduces inter-frame jitter and dynamically adapts to the client CPU load and network congestion. Our WWW server dynamically changes transfer protocols, adapting to the request stream and the metainformation in requested documents. Experiments show a 44-fold increase in received video-frame rate (0.2 frames-per-second (Jps) to 9 fps) with the use of VDP in lieu of TCP, with a commensurate improvement in observed video quality. Our work enables a video-enhanced Web.