A proactive implementation of interactive video-on-demand

Most broadcasting protocols for video-on-demand do not allow the customer to pause, move fast-forward or backward while watching a video. We propose a broadcasting protocol implementing these features in a purely proactive fashion. Our protocol implements rewind and pause interactions at the set-top box level by requiring the set-top box to keep in its buffer all video data it has received from the server until the customer has finished watching the video. It implements fast-forward by letting the video server transmit video data more frequently than needed by customers watching the video in sequence. As a result, any customer having watched the first x minutes of a video will be able to fast-forward to any scene within the first 2x or 3x minutes of the video. We show that this expanding horizon feature can be provided at a reasonable cost. We also show how our protocol can accommodate customers connected to the service through a device lacking either the ability to receive data at more than two times the video consumption rate or the storage space required to store more than 20 to 25 percent of the video they are watching. While these customers will not have access to any of the interactive features provided by our protocol, they will be able to watch videos after the same wait time as all other customers