Even though it is technically feasible, service providers have been hesitant to make the investment necessary for wide-scale deployment. Furthermore, almost all of the trials to date suggest VoD is too expensive and there is too little demand. The jukebox paradigm offers a compromise between two types of program scheduling. At one end of the scheduling spectrum, a set of broadcast TV channels each carry a pre-set schedule of programs. At the other end of the spectrum, VoD programs are transmitted to individual users only when the user makes a request.
Broadcast TV offers choice only through the variety of available channels.
In a VoD system, users control what they receive, but the size of such a system grows proportionally to the number of users. The goal of the jukebox paradigm is to offer some amount of user choice while eliminating the near-linear relationship between system size and user population. The jukebox provides a set of channels which are multicast to all users watching each channel. Users' program requests are scheduled on one of the jukebox's channels using criteria ranging from simple to complex. One possibility is to schedule a request on the channel with the shortest wait time.