Layered range multicast for video on demand

We focus on the problem of providing quality-ofservice guarantee, scalability, and on-demand property to video streaming systems. We propose a solution called Layered Range Multicast (LRM). LRM allows transmitting a range of data to a multicast group’s members, which helps clients who request for service at different times join a same multicast efficiently without additional server bandwidth allocation. This is more advanced than the conventional multicast in which a late client joining an existing multicast, without bandwidth support from the server, must miss a certain portion of the video requested. Another advantage of LRM is its capability to support clients requesting various levels of service quality. In addition, LRM does not assume the existence of IP Multicast and therefore it can be implemented on the current Internet without degrading to the very inefficient centralized approach. Our performance study results confirm the above benefits.