On-demand delivery of audiovisual content or other media content over broadband services may involve delivery of very large media files over broadband connections of varying speed and stability. Because available bandwidth may vary with network usage, location of the receiving device relative to a host or a server, and other factors, a delivery method that may be appropriate for one user at one location and at one particular time may not be satisfactory for another user at a different location or at a different time.
For example, while a first user at a first location may be able to stream motion video media content at high resolution at any time of day or night without playback stoppages, a second user at a second location may be able to satisfactorily stream motion video content only during low usage hours. During higher usage hours, the second user may instead download media content to avoid frequent playback stoppages. Progressive downloading, in which metadata about the media file is stored in the first part of the file to be transmitted, allows playback to begin before all of the media content is fully downloaded. Like streaming, however, progressive downloading permits the start of playback usually only after a certain portion of the media content has already been received in hopes of avoiding playback stoppages.
An additional problem arises when, during the delivery of the media file via streaming or downloading, the condition of the communication connection changes. For example, at a location where streaming was available at one time, increasing network usage or other changes affecting the communication connection may prevent satisfactory streaming. Conversely, it is possible that at a second location and at a second time, satisfactory streaming may not have been available but may become available.